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Article

Photo-Thermal Synergistic Catalytic Oxidative Dehydrogenation of Propane over NiO Nanoparticle-Decorated Graphitic Carbon Nitride

by
Pengcheng Dai
1,*,
Hui Zhao
1,
Dehong Yang
2,
Yongxin Zhao
1,
Longzhen Cheng
1,
Huishan Chen
1,
Dongzhi Jiang
1 and
Yilong Cui
1
1
Shandong Key Laboratory of Advanced Electrochemical Energy Storage Technologies, College of New Energy, China University of Petroleum (East China), Qingdao 266580, China
2
National Laboratory of Solid State Microstructures (NLSSM), Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China
*
Author to whom correspondence should be addressed.
Catalysts 2025, 15(10), 919; https://doi.org/10.3390/catal15100919
Submission received: 1 July 2025 / Revised: 16 September 2025 / Accepted: 19 September 2025 / Published: 24 September 2025
(This article belongs to the Section Catalytic Reaction Engineering)
Browse Figures
Versions Notes

Abstract

The oxidative dehydrogenation of propane (ODHP) catalyzed by oxygen offers several advantages, including resistance to carbon deposition and low energy consumption. However, achieving high propylene selectivity at industrially relevant conversions remains challenging, as existing catalysts typically require temperatures exceeding 500 °C, promoting over-oxidation to COx. In this study, we developed a NiO nanoparticle-decorated graphitic carbon nitride catalyst (NiO@CN-600) via thermal polymerization–oxidation for photo-thermal synergistic ODHP. At 430 °C, thermal catalysis achieved a propane conversion of 14%. Remarkably, introducing light irradiation boosted conversion to 24%, a 10% increase. Further experimental results reveal that the photo-thermal synergistic catalysis can be described by the following mechanism: initial thermal energy provides sufficient activation energy, enabling the reaction to overcome the energy barrier and proceed smoothly. Simultaneously, the introduction of light energy enhances the activity of lattice oxygen, making it more likely to detach from the lattice and form oxygen vacancies, which in turn boosts the efficiency of the oxidation reaction on the catalyst surface.

1. Introduction

Propylene, a key raw material in the chemical industry, is widely used in the production of various important organic chemicals, including polypropylene, propylene oxide, and cumene [1,2]. Compared to the commercially developed direct propane dehydrogenation (DHP) reaction, oxidative dehydrogenation of propane (ODHP) offers exothermic reaction characteristics, theoretically enabling high conversion rates at lower temperatures (<500 °C) with minimal carbon deposition [3,4,5]. This makes ODHP a promising alternative to DHP for propylene production [6]. However, due to the stronger stability of the C-H bonds in propane compared to those in propylene, the main product, propylene, is more prone to over-oxidation to COx [7,8]. For example, at 10% propane conversion, the propene selectivity typically drops to less than 60% for such conventional catalysts [9].
After decades of research, numerous outstanding studies have developed a series of catalysts with excellent selectivity control. For example, graphene-like h-BN [10] and other boron-based catalysts maintain a total olefin selectivity of 90% at moderate conversion rates (~14%) [11,12,13,14,15]. However, boron-based ODHP catalysts typically require high reaction temperatures, often exceeding 500 °C, to achieve satisfactory propane conversion [16,17,18]. At these elevated temperatures, C-C bond cleavage, with an average bond energy of 347 kJ·mol−1 [19], occurs more readily than C-H bond activation, which has an average bond energy of 401 kJ·mol−1 [20]. This preference results in the formation of deep oxidation products, which significantly reduce the selectivity and single-pass yield of the target product, propene [21,22]. Therefore, designing new catalysts and reaction modes that can lower reaction temperatures, suppress deep oxidation reactions, and enhance propene selectivity while maintaining high propane conversion rates remains a significant challenge in this field [11,23,24].
Photo-thermal synergistic catalysis, which integrates traditional thermal catalysis with semiconductor photocatalysis, has emerged as a highly effective approach to reduce catalytic reaction temperatures and achieve higher yields of target products under milder conditions [25,26,27]. In our previous research, we developed a semiconducting boron-carbon-nitride (BCN) catalyst that significantly improved propane conversion while preserving propene selectivity through the effects of photo-thermal synergy [28]. The carriers generated by light irradiation effectively reduced the thermal energy required to surmount reaction barriers, leveraging both light and thermal energy as driving forces for the reaction. Furthermore, the novel Cu/BN photothermal catalytic system leverages the localized surface plasmon resonance (LSPR) effect of copper nanoparticles (Cu-NPs) to significantly enhance the photothermal catalytic performance of the BN support, thereby enabling higher propane conversion and improved propylene selectivity under moderate temperature conditions [29]. Nevertheless, even in photo-thermal synergistic conditions, a high temperature was necessary to achieve a moderate propene yield. This highlights the imperative for developing novel catalysts that can further lower reaction temperatures. Inspired by these concepts and findings, we turn our focus to NiO catalytic materials, which exhibit excellent low-temperature activation of alkanes [30,31,32]. Furthermore, as a p-type semiconductor, NiO has strong hole mobility, high cost-effectiveness, and excellent redox capabilities [33]. However, its small visible light absorption range and rapid recombination of photogenerated electron–hole pairs limit its visible-light activation performance, leading to low photocatalytic efficiency. Additionally, bulk NiO tends to favor the combustion of propane rather than selective oxidation, so dispersing it onto a support is an effective strategy for achieving selective oxidation [30]. Among the potential support materials, graphitic carbon nitride (g-C3N4) stands out due to its highly lattice-matched structure, relatively narrow bandgap (~2.7 eV), and excellent chemical and thermal stability, making it an ideal platform for anchoring NiO nanoparticles [34]. The combination of g-C3N4 with NiO not only enhances light-harvesting efficiency but also significantly improves charge carrier separation through the formation of a heterojunction, thereby boosting photocatalytic activity. Moreover, NiO/g-C3N4 composites have demonstrated outstanding photocatalytic performance in reactions such as CO2 reduction and pollutant degradation, owing to the efficient interfacial charge transfer and the synergistic interaction between the two semiconductors [35,36].
In this work, we discovered that graphitic carbon nitride (g-C3N4) modified with NiO nanoparticles (NiO@CN) can serve as an efficient photo-thermal synergistic catalyst for ODHP reactions at significantly lower temperatures. The NiO@CN was synthesized via a thermal polymerization–oxidation method and consists of highly dispersed NiO nanoparticles on g-C3N4 nanosheets, exhibiting good structural stability and efficient light absorption properties. At a reaction temperature of 430 °C, the propane conversion under thermal catalytic conditions reached 14%. Under photo-thermal catalytic conditions, the increase further rose to 24%, representing a 10% increase. The enhanced catalytic efficiency is primarily attributed to NiO@CN’s strong light absorption capability, its appropriate band structure, and the improved lattice oxygen activity following light irradiation. This newly proposed photo-thermal synergistic catalytic ODHP system not only expands the application of photo-thermal catalysis but also provides a practical pathway for activating low-carbon alkanes under milder conditions.

2. Results and Discussion

2.1. Structural and Compositional Analyses

The synthesis of NiO@CN-x (x = 400, 600, 800) is illustrated in Figure 1a. Initially, melamine was dissolved in deionized water, after which nickel nitrate was added and thoroughly mixed. The solvent was then evaporated in a water bath, yielding the precursor, which was subsequently heat-treated to obtain the desired product. To determine the optimal NiO loading, the catalytic performance was investigated at 400 °C. As shown in Figure S2, the best catalytic performance was achieved by NiO@CN-600. Although reducing the NiO loading resulted in excellent olefin selectivity, the catalytic activity was poor. Conversely, increasing the NiO loading slightly improved catalytic activity, but selectivity decreased sharply, likely due to the formation of larger NiO particles [30]. Therefore, the NiO@CN-600 sample was used for further investigation of catalytic performance and exploration of the mechanism. The X-ray diffraction pattern of the NiO@CN-600 sample reveals three distinct diffraction peaks, as shown in Figure 1b. Two prominent peaks appear at 13.1° and 27.6° for g-C3N4 nanosheets, reflecting the periodic structure of intra-planar tri-s-triazine packing as the (100) peak and the interlayer stacking of conjugated aromatic structures as the (002) peak for graphitic materials, respectively [37,38]. The prepared NiO@CN displays three smaller peaks at 37.2°, 43.4°, and 62.9°, corresponding to the (111), (200), and (220) planes of cubic NiO (JCPDS 47-1049) [39], respectively. Furthermore, compared to g-C3N4, the addition of NiO led to a decrease in the intensity of the diffraction peaks of g-C3N4, according to the Scherrer equation Lc = 0.89λ/Bcosθ, where Lc, λ, B, and θ represent the crystallite size, the X-ray wavelength, the full width at half maximum (FWHM) of the diffraction peak in (002), the Bragg angle, respectively. The crystallite sizes were approximately 5.25 nm for g-C3N4 and 4.37 nm for NiO@CN-600, respectively. Indicating a minor disturbance in the crystalline structure, the overall structure of g-C3N4 remains largely preserved, and no significant phase change was observed. Figure S3 presents the FT-IR spectra of the as-prepared NiO@CN-600. Both g-C3N4 and NiO@CN-600 show a broad peak in the range of 1200–1650 cm−1 and a sharp peak at 811 cm−1, corresponding to the stretching vibration mode of the aromatic C-N bond and the bending vibration of the triazine ring, respectively [40]. However, the peak intensity of NiO@CN-600 is significantly lower compared to that of pure g-C3N4. This observation reinforces the idea that the NiO and g-C3N4 composite is a more complex entity than merely a mechanical mixture of the two [34]. NiO@CN-600 exhibits a typical IV-type curve with an H3-type hysteresis loop, indicating that NiO@CN-600 possesses a mesoporous structure, as confirmed by the nitrogen adsorption–desorption isotherms (Figure 1c). The pore size distribution shown in the inset further verifies that the pore sizes of NiO@CN-600 are primarily distributed in the range of 5–20 nm. The appropriate pore structure and specific surface area (64.6 m2 g−1) facilitate mass transfer, which enhances the reaction process. Figure 1d displays the thermogravimetric analysis (TGA) curve of NiO@CN-600 in an air atmosphere. It is noted that NiCN-600 begins to decompose at approximately 500 °C. This elevated decomposition temperature is crucial for conducting the ODHP within our temperature range for catalytic evaluation (370–430 °C).
The SEM images show that the synthesized NiO@CN-600 exhibits a two-dimensional layered stacking structure similar to that of g-C3N4, indicating that the doping of NiO during synthesis does not alter the morphological state of the g-C3N4 substrate (Figure 2a,b). The elemental distribution images show that the four elements C, N, Ni, and O are uniformly distributed in NiO@CN-600 (Figure 2c). These results confirm the successful preparation of NiO@CN. The high dispersion of NiO on the carrier g-C3N4 provides more active sites for the catalytic reaction, thereby enhancing the catalytic activity. Further TEM analysis reveals that the NiO nanoparticles were uniformly distributed on g-C3N4 with consistent sizes around 5–7 nm (Figure 2d,e). The lattice stripe of 0.21 nm corresponds to the (200) plane of NiO (Figure 2f), confirming that the NiO nanoparticles exist in the form of cubic NiO, which is consistent with the characterization results of XRD. Notably, in the case of NiO@CN-400, the insufficient NiO content results in a low density of active sites, leading to limited propane conversion despite relatively high propylene selectivity (Figure S4a,b). Conversely, NiO@CN-800 contains an excessive amount of NiO, which may lead to partial nanoparticle aggregation and undesired overoxidation of propane, thereby reducing selectivity (Figure S3c,d). Among the three, NiO@CN-600 exhibits the most balanced performance, achieving an optimal compromise between activity and selectivity due to its moderate NiO loading. These findings suggest that in this catalyst system, NiO loading plays a dominant role in determining catalytic behavior, rather than particle size.
Furthermore, the Ni content in the NiO/g-C3N4 composite was determined by ICP-OES analysis to be 2.478 wt% (Table S1). Assuming all the Ni originates from NiO, the total NiO content is estimated to be approximately 3.15 wt%, corresponding to a g-C3N4 content of 96.85 wt%. This indicates a NiO to g-C3N4 weight ratio of approximately 1:30.7. This suggests that the actual NiO loading in the composite is consistent with the intended low loading, and confirms the successful incorporation of NiO onto the g-C3N4 framework.
XPS further investigated the surface chemical state of NiO@CN-600. As shown in the C 1s spectrum (Figure 3a), the peak at 288.1 eV is attributed to the triazine rings containing N-C=N bonds with sp2 hybridization. The peak at 284.8 eV is assigned to the C-C bond [41,42]. The high-resolution spectra for N 1s (Figure 3b) show a prominent peak at 398.5 eV, which is attributed to the sp2 hybridized aromatic nitrogen (C-N=C) in the triazine ring [43]. The peak at 399.7 eV is assigned to the N-(C)3 group. The peak at 400.9 eV is attributed to the amino functional group (C-N-H), which results from the incomplete condensation of the polytriazine structure [44]. There are four kinds of Ni species in the Ni 2p spectrum (Figure 3c). The peaks at 855.6 eV and 872.6 eV correspond to Ni 2p3/2 and Ni 2p1/2, respectively, which are attributed to Ni2+ in NiO. The two peaks at 861.5 eV and 881.1 eV are attributed to oscillatory and satellite peaks resulting from oscillations [39,45]. The peaks at 532.1 eV in the O 1s spectrum were attributed to the lattice oxygen of NiO (Figure 3d), in agreement with the high-resolution spectral analysis of the Ni 2p. This further demonstrates the presence of NiO.
A key indicator of the photo-thermal co-catalytic performance of the catalyst is its optical properties. According to ultraviolet–visible diffuse reflectance spectroscopy (UV-Vis DRS), g-C3N4 exhibits light absorption wavelengths that extend into the visible spectrum, with an absorption edge at approximately 600 nm (Figure 4a). This observation is consistent with the actual color of the catalyst (brownish-yellow) and indicates highly efficient light absorption properties. The optical band gap (Eg) of g-C3N4 can be estimated from the Tauc plot, αhν = A(hν − Eg)n, where α, h, v, A and Eg represent the adsorption coefficient, Planck’s constant, the light frequency, a constant relative to the material and the band gap energy, respectively. Furthermore, n is dependent on the type of transition in a semiconductor. Figure 4b shows a strong linear fit when using n = 2, indicating that g-C3N4 is a direct band gap material, which aligns with previous reports [46]. Thus, the band gap of g-C3N4 was determined to be 2.16 eV by measuring the x-axis intercept of an extrapolated line from the linear regime of the curve. Ultraviolet photoelectron spectroscopy (UPS) was employed to further investigate the energy band structure of g-C3N4. The valence band (VB) of g-C3N4 was calculated to be −6.92 eV (vacuum energy level) by subtracting the width of the UPS spectrum from the excitation energy (21.22 eV) [47] (Figure 4c). Based on these results, the conduction band (CB) of g-C3N4 was found to be −4.76 eV (vacuum energy level) by subtracting the band gap energy from the valence band energy. Furthermore, a typical band structure of NiO nanoparticles features a valence band at −5.79 eV and a conduction band at −2.49 eV versus the vacuum level [35]. As illustrated in the band diagram (Figure 4d), the redox potentials for the reduction of oxygen to hydrogen peroxide and water lie within the band edges of the heterostructure. This indicates that NiO@CN-600 possesses the capability to activate molecular oxygen under light irradiation [48].

2.2. Catalytic ODHP Performances

The as-prepared NiO@CN-600 was utilized in thermal and photo-thermal catalysis for ODHP to examine the effect of light. The catalyst exhibited excellent low-temperature catalytic performance, activating at 370 °C (Figure 5a). At a reaction temperature of 410 °C, the thermally catalyzed propane conversion was 10%. Under photo-thermal catalytic conditions, it increased to 15%, with a selectivity of approximately 60% (Figure 5b). The reaction between propane and oxygen primarily yields propylene and COx (Figure 5a,b). Furthermore, mass spectrometry results confirm that no other propylene oxide species were detected (Figure S6). As the temperature rose, the propane conversion under photo-thermal catalysis reached 24% at 430 °C, whereas it was only 14% under thermal catalysis. Notably, the propylene yield varied from 7% to 10% at 420 °C (Figure 5c). Additionally, the propylene selectivity remained relatively constant. Stability tests were performed at a reaction temperature of 410 °C for 10 h. The catalytic activity was compared under thermal and photo-thermal conditions to distinguish the roles of light and heat. Figure 5d shows that propane conversion increased reversibly in all three cycles of thermal-photothermal catalysis from around 10% to about 15%, while propylene selectivity stayed stable throughout the experiment. Moreover, the carbon balance was consistently maintained at 100 ± 2%, indicating no carbon deposition or decomposition of NiO@CN-600 during testing (Figure 5e). These results suggest that introducing light into ODHP can enhance propane conversion while preserving propylene selectivity. Furthermore, the reaction temperatures for different catalysts at moderate conversions were compared, revealing that the catalytic activity of NiO@CN-600 was superior to that of some other classical catalysts documented in the literature [10,12,23,24,32,49,50,51,52,53] (Figure 5f, Table S2). The findings suggest that the NiO@CN-600 demonstrates considerable advantages regarding catalytic performance, particularly at low temperatures. In addition, it should be emphasized that the current catalytic performance (~24% conversion with ~60% propene selectivity) remains below the threshold required for industrial-scale propane dehydrogenation or oxidative dehydrogenation. Further advancements in catalyst design, reactor configuration, and process integration will therefore be essential to improve both efficiency and stability.
To further elucidate the role of catalyst in photo-thermal synergistical ODHP, comprehensive post-reaction characterization of NiO@CN-600 was conducted. XRD analysis (Figure 6a) revealed that the diffraction peaks of cubic nickel oxide intensified after the stability test, suggesting NiO as the active species and validating the Mars–Van Krevelen mechanism. Figure 6b displays the nitrogen adsorption–desorption curves and pore size distribution of NiO@CN-600 after stability test. Compared to the pre-reaction period, the specific surface area and pore size of NiO@CN-600 remained relatively unchanged, indicating the preservation of the porous framework. The Ni 2p spectra reveal that the valence state of Ni species remained essentially unchanged before and after the reaction (Figure S7), indicating that the NiO component retained its oxidation state during the photo-thermal ODHP process. Morphological integrity was evidenced by SEM imaging (Figure 6c,d). The reacted NiO@CN-600 retained its original two-dimensional lamellar architecture without collapse, confirming exceptional structural robustness throughout the photo-thermal catalytic process.
Additionally, to demonstrate the contribution of g-C3N4 to the reaction system, pure g-C3N4 was evaluated under identical ODHP conditions. Thermal catalytic testing revealed low propane conversion over g-C3N4, with values of 0.7%, 0.9%, 1%, 1.5%, and 1.9% observed at temperatures ranging from 370 °C to 430 °C. Notably, upon light illumination, the conversion further decreased to 0.5%, 0.7%, 0.9%, 1.1%, and 1.5%, respectively (Figure 7a), exhibiting an inverse trend to that of NiO@CN-600. This contrast demonstrates that g-C3N4 primarily functions as a catalytic support, whereas NiO serves as the active phase for ODHP, aligning with the post-reaction XRD analysis of NiO@CN-600. Further investigation into the influence of light intensity on NiO@CN-600’s catalytic performance, conducted at a fixed temperature (Figure 7b), demonstrated a positive correlation between light intensity and propane conversion. However, propylene selectivity exhibited a concomitant decrease. This phenomenon is attributed to the light-induced enhancement in lattice oxygen activity, which is widely recognized as the key active site in metal oxide catalysts for the oxidative dehydrogenation of low-carbon alkanes [54,55,56]. To probe the light-mediated changes in lattice oxygen, electron paramagnetic resonance (EPR) spectroscopy was employed to characterize surface oxygen vacancies. As depicted in Figure 7c, the EPR signal intensity at g ≈ 2.003 was more vigorous under light irradiation compared to dark conditions. This observation reveals that light irradiation promotes the generation and activity of oxygen vacancies on the NiO@CN-600 surface, thereby enhancing its capacity for oxygen activation and consequently increasing propane conversion. Finally, the catalytic activity of NiO@CN-600 was assessed under purely photocatalytic conditions. As shown in Figure S8, negligible propane conversion occurred under photocatalysis alone. This finding highlights that thermal energy serves as the primary driving force for the photo-thermal ODHP reaction over NiO@CN-600, while light energy provides an additional activation pathway for the reactants beyond thermal catalysis (Figure 7d). The catalytic effect under photo-thermal synergistic conditions transcends the simple additive performance of photocatalysis and thermal catalysis alone, effectively achieving synergistic coupling.

3. Materials and Methods

3.1. Materials and Chemicals

Anhydrous melamine (C3H6N6, 99%) was purchased from Sigma-Aldrich (Saint Louis, MO, USA). Nitrate hexahydrate (Ni (NO3)2·6H2O, AR) was purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). Deionized water was self-made.

3.2. Synthesis of g-C3N4 and NiO@CN-x (x = 400, 600, 800)

10 g of melamine was added to a beaker containing 200 mL of deionized water and then transferred to a constant temperature magnetic stirrer for 15 min of stirring. Subsequently, x (x = 400, 600, 800) mg of nickel nitrate hexahydrate was added, and the heating temperature was adjusted to 90 °C for vigorous stirring until the water evaporated. The resulting product was collected and placed in a covered porcelain boat, then heated under an argon atmosphere at a rate of 2 °C·min−1 to 550 °C, where it was maintained for 4 h. After natural cooling to room temperature, the sample was removed and ground into powder. 2 g of the resulting powder was placed in a porcelain boat and heated in a static air atmosphere at a rate of 10 °C·min−1 to 450 °C, followed by a 3 h holding time. After natural cooling to room temperature, the sample was labeled as NiO@CN-x. For the preparation of pure g-C3N4, the synthesis procedure remained the same as described above, except for the omission of nickel nitrate hexahydrate.

4. Conclusions

In summary, we successfully synthesized NiO nanoparticle-decorated graphitic carbon nitride (NiO@CN-600) via a thermal polymerization–oxidation method. The catalyst demonstrated exceptional photo-thermal synergistic catalytic performance for the oxidative dehydrogenation of propane (ODHP) at significantly reduced temperatures (370–430 °C). At 430 °C, NiO@CN-600 achieved a propane conversion of 14% under thermal catalysis. Remarkably, under photo-thermal synergistic conditions, the conversion substantially increased to 24%, representing a significant 10% enhancement. This boost is attributed to the synergistic interplay of thermal and light energy. Thermal energy provides the necessary activation energy to overcome the reaction barrier, while light irradiation enhances the activity of lattice oxygen, promoting the formation of oxygen vacancies and accelerating the surface oxidation reaction. It should be noted that the propylene formation rate in this study appears lower than some previously reported thermal catalytic systems, which is likely attributed to the lower propane partial pressure employed in our experiments. Further investigations will be conducted at various propane partial pressures (e.g., 0.1–0.5 atm) to allow for a more comprehensive comparison and a fuller assessment of the catalyst’s performance.

Supplementary Materials

The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/catal15100919/s1, Figure S1 Schematic illustration of the fixed-bed microreactor for the photo-thermal catalytic oxidative dehydration of propane reaction; Figure S2 Catalytic performance of catalysts with different additions of NiO@CN-x at 400 °C; Figure S3 FT-IR absorption images of NiO@CN-600 and g-C3N4; Figure S4 (a) TEM images of NiO@CN-400. (b) HR-TEM image of NiO@CN-400. (c) TEM images of NiO@CN-800. (d) HR-TEM image of NiO@CN-800. Figure S5 (a) GC-FID analysis spectrum. (b) GC-TCD analysis spectrum. Figure S6 MS analysis spectrum. Figure S7 Ni 2p high-resolution spectrum of NiO@CN-600 after stability test. Figure S8 Performance of NiO@CN-600 photocatalytic ODHP. Table S1 Ni content determined by ICP-OES. Table S2 Summary of the catalytic performance of NiO@CN-600 and other reported catalysts for ODHP.

Author Contributions

Conceptualization, P.D.; methodology, H.Z. and D.Y.; software, H.Z.; validation, Y.Z.; formal analysis, L.C.; investigation, H.C.; resources, D.J.; data curation, Y.C.; writing—original draft preparation, H.Z.; writing—review and editing, P.D.; visualization, H.Z.; supervision, P.D. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the National Natural Science Foundation of China (51702365) and the Natural Science Foundation of Shandong Province (ZR2022MB133).

Data Availability Statement

The data presented in this study are available upon request from the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Torres Galvis, H.M.; Bitter, J.H.; Khare, C.B.; Ruitenbeek, M.; Dugulan, A.I.; de Jong, K.P. Supported Iron Nanoparticles as Catalysts for Sustainable Production of Lower Olefins. Science 2012, 335, 835–838. [Google Scholar] [CrossRef] [PubMed]
  2. Sattler, J.J.H.B.; Ruiz-Martinez, J.; Santillan-Jimenez, E.; Weckhuysen, B.M. Catalytic Dehydrogenation of Light Alkanes on Metals and Metal Oxides. Chem. Rev. 2014, 114, 10613–10653. [Google Scholar] [CrossRef]
  3. Gao, X.; Liu, M.; Huang, Y.; Xu, W.; Zhou, X.; Yao, S. Dimensional Understanding of Boron-Based Catalysts for Oxidative Propane Dehydrogenation: Structure and Mechanism. ACS Catal. 2023, 13, 9667–9687. [Google Scholar] [CrossRef]
  4. Venegas, J.M.; McDermott, W.P.; Hermans, I. Serendipity in Catalysis Research: Boron-Based Materials for Alkane Oxidative Dehydrogenation. Acc. Chem. Res. 2018, 51, 2556–2564. [Google Scholar] [CrossRef] [PubMed]
  5. Rightor, E.G.; Tway, C.L. Global energy & emissions reduction potential of chemical process improvements. Catal. Today 2015, 258, 226–229. [Google Scholar] [CrossRef]
  6. Carrero, C.A.; Schloegl, R.; Wachs, I.E.; Schomaecker, R. Critical Literature Review of the Kinetics for the Oxidative Dehydrogenation of Propane over Well-Defined Supported Vanadium Oxide Catalysts. ACS Catal. 2014, 4, 3357–3380. [Google Scholar] [CrossRef]
  7. Xie, B.; Hu, D.; Kumar, P.; Ordomsky, V.V.; Khodakov, A.Y.; Amal, R. Heterogeneous catalysis via light-heat dual activation: A path to the breakthrough in C1 chemistry. Joule 2024, 8, 312–333. [Google Scholar] [CrossRef]
  8. Cavani, F.; Ballarini, N.; Cericola, A. Oxidative dehydrogenation of ethane and propane: How far from commercial implementation? Catal. Today 2007, 127, 113–131. [Google Scholar] [CrossRef]
  9. Shi, L.; Wang, D.; Lu, A.-H. A viewpoint on catalytic origin of boron nitride in oxidative dehydrogenation of light alkanes. Chin. J. Catal. 2018, 39, 908–913. [Google Scholar] [CrossRef]
  10. Grant, J.T.; Carrero, C.A.; Goeltl, F.; Venegas, J.; Mueller, P.; Burt, S.P.; Specht, S.E.; McDermott, W.P.; Chieregato, A.; Hermans, I. Selective oxidative dehydrogenation of propane to propene using boron nitride catalysts. Science 2016, 354, 1570–1573. [Google Scholar] [CrossRef]
  11. Cao, L.; Dai, P.; Tang, J.; Li, D.; Chen, R.; Liu, D.; Gu, X.; Li, L.; Bando, Y.; Ok, Y.S.; et al. Spherical Superstructure of Boron Nitride Nanosheets Derived from Boron-Containing Metal–Organic Frameworks. J. Am. Chem. Soc. 2020, 142, 8755–8762. [Google Scholar] [CrossRef]
  12. Shi, L.; Wang, D.; Song, W.; Shao, D.; Zhang, W.-P.; Lu, A.-H. Edge-hydroxylated Boron Nitride for Oxidative Dehydrogenation of Propane to Propylene. ChemCatChem 2017, 9, 1788–1793. [Google Scholar] [CrossRef]
  13. Xiao, F.; Naficy, S.; Casillas, G.; Khan, M.H.; Katkus, T.; Jiang, L.; Liu, H.; Li, H.; Huang, Z. Hydrogels: Edge-Hydroxylated Boron Nitride Nanosheets as an Effective Additive to Improve the Thermal Response of Hydrogels (Adv. Mater. 44/2015). Adv. Mater 2015, 27, 7247. [Google Scholar] [CrossRef]
  14. Ding, D.; Yan, B.; Wang, Y.; Lu, A.-H. Fabrication of h-BN/SiO2 Nanofibers Showing High Olefins Productivity in Oxidative Dehydrogenation of Propane. ChemCatChem 2021, 13, 3312–3318. [Google Scholar] [CrossRef]
  15. Liu, Z.; Yan, B.; Meng, S.; Liu, R.; Lu, W.-D.; Sheng, J.; Yi, Y.; Lu, A.-H. Plasma Tuning Local Environment of Hexagonal Boron Nitride for Oxidative Dehydrogenation of Propane. Angew. Chem. Int. Ed. 2021, 60, 19691–19695. [Google Scholar] [CrossRef]
  16. Altvater, N.R.; Dorn, R.W.; Cendejas, M.C.; McDermott, W.P.; Thomas, B.; Rossini, A.J.; Hermans, I. B-MWW Zeolite: The Case Against Single-Site Catalysis. Angew. Chem. Int. Ed. 2020, 59, 6546–6550. [Google Scholar] [CrossRef]
  17. Belgamwar, R.; Rankin, A.G.M.; Maity, A.; Mishra, A.K.; Gómez, J.S.; Trébosc, J.; Vinod, C.P.; Lafon, O.; Polshettiwar, V. Boron Nitride and Oxide Supported on Dendritic Fibrous Nanosilica for Catalytic Oxidative Dehydrogenation of Propane. ACS Sustain. Chem. Eng. 2020, 8, 16124–16135. [Google Scholar] [CrossRef]
  18. Grant, J.T.; McDermott, W.P.; Venegas, J.M.; Burt, S.P.; Micka, J.; Phivilay, S.P.; Carrero, C.A.; Hermans, I. Boron and Boron-Containing Catalysts for the Oxidative Dehydrogenation of Propane. ChemCatChem 2017, 9, 3623–3626. [Google Scholar] [CrossRef]
  19. Li, P.; Zhang, X.; Wang, J.; Xue, Y.; Yao, Y.; Chai, S.; Zhou, B.; Wang, X.; Zheng, N.; Yao, J. Engineering O–O Species in Boron Nitrous Nanotubes Increases Olefins for Propane Oxidative Dehydrogenation. J. Am. Chem. Soc. 2022, 144, 5930–5936. [Google Scholar] [CrossRef]
  20. Yao, Y.; Wang, J.; Lu, F.; Li, W.; Mei, B.; Zhang, L.; Yan, W.; Yuan, F.; Jiang, G.; Senanayake, S.D.; et al. Suppressing COx in oxidative dehydrogenation of propane with dual-atom catalysts. Nat. Commun. 2025, 16, 4639. [Google Scholar] [CrossRef]
  21. Venegas, J.M.; Zhang, Z.; Agbi, T.O.; McDermott, W.P.; Alexandrova, A.; Hermans, I. Why Boron Nitride is such a Selective Catalyst for the Oxidative Dehydrogenation of Propane. Angew. Chem. Int. Ed. 2020, 59, 16527–16535. [Google Scholar] [CrossRef]
  22. Chen, H.; Jiang, D.-e.; Yang, Z.; Dai, S. Engineering Nanostructured Interfaces of Hexagonal Boron Nitride-Based Materials for Enhanced Catalysis. Acc. Chem. Res. 2023, 56, 52–65. [Google Scholar] [CrossRef]
  23. Gao, X.; Zhu, L.; Yang, F.; Zhang, L.; Xu, W.; Zhou, X.; Huang, Y.; Song, H.; Lin, L.; Wen, X.; et al. Subsurface nickel boosts the low-temperature performance of a boron oxide overlayer in propane oxidative dehydrogenation. Nat. Commun. 2023, 14, 1478. [Google Scholar] [CrossRef] [PubMed]
  24. Cao, L.; Dai, P.; Wen, S.; Jiang, Y.; Liu, D.; Gu, X.; Zhang, Q.; Xia, Y.; Zhong, G.; Zhao, X.; et al. A thermostable pillared layered metal-borate- organic network featuring neighboring boron sites for oxidative dehydrogenation of propane. Matter 2023, 6, 4376–4387. [Google Scholar] [CrossRef]
  25. He, Z.-H.; Wu, B.-T.; Wang, Z.-Y.; Yang, S.-Y.; Wang, K.; Shi, J.-J.; He, M.-X.; Wang, W.; Liu, Z.-T. Photothermal catalytic CO2 oxidative dehydrogenation of propane to propylene over BiOX (X = Cl, Br, I) nanocatalysts. Green Chem. 2022, 24, 8270–8279. [Google Scholar] [CrossRef]
  26. Wang, Z.; Yang, Z.; Kadirova, Z.C.; Guo, M.; Fang, R.; He, J.; Yan, Y.; Ran, J. Photothermal functional material and structure for photothermal catalytic CO2 reduction: Recent advance, application and prospect. Coord. Chem. Rev. 2022, 473, 214794. [Google Scholar] [CrossRef]
  27. Kang, L.; Liu, X.Y.; Wang, A.; Li, L.; Ren, Y.; Li, X.; Pan, X.; Li, Y.; Zong, X.; Liu, H.; et al. Photo–thermo Catalytic Oxidation over a TiO2-WO3-Supported Platinum Catalyst. Angew. Chem. Int. Ed. 2020, 59, 12909–12916. [Google Scholar] [CrossRef]
  28. Yang, D.; Liu, D.; Li, Y.; Gan, H.; Xu, P.; Tian, Y.; Li, Z.; Xing, T.; Gu, X.; Li, L.; et al. Photo-thermal synergistic catalytic oxidative dehydrogenation of propane over a spherical superstructure of boron carbon nitride nanosheets. Appl. Surf. Sci. 2023, 639, 158258. [Google Scholar] [CrossRef]
  29. Sun, S.; Zhao, M.; Liu, H.; Li, D.; Lei, Y. Photothermal oxidative dehydrogenation of propane to propylene over Cu/BN catalysts. Front. Chem. 2024, 12, 1439185. [Google Scholar] [CrossRef]
  30. Lu, H.-Q.; Shi, L.; He, C.; Weng, W.-Z.; Huang, C.-J.; Wan, H.-L. Highly-Dispersed NiO Nanoparticles on SBA-15 for Oxidative Dehydrogenation of Propane to Propylene. Acta Phys. Chim. Sin. 2012, 28, 2697–2704. [Google Scholar] [CrossRef]
  31. Zhang, X.; You, R.; Li, D.; Cao, T.; Huang, W. Reaction Sensitivity of Ceria Morphology Effect on Ni/CeO2 Catalysis in Propane Oxidation Reactions. ACS Appl. Mater. Interfaces 2017, 9, 35897–35907. [Google Scholar] [CrossRef] [PubMed]
  32. Li, J.-H.; Wang, C.-C.; Huang, C.-J.; Sun, Y.-F.; Weng, W.-Z.; Wan, H.-L. Mesoporous nickel oxides as effective catalysts for oxidative dehydrogenation of propane to propene. Appl. Catal., A 2010, 382, 99–105. [Google Scholar] [CrossRef]
  33. Egbo, K.O.; Liu, C.P.; Ekuma, C.E.; Yu, K.M. Vacancy defects induced changes in the electronic and optical properties of NiO studied by spectroscopic ellipsometry and first-principles calculations. J. Appl. Phys. 2020, 128. [Google Scholar] [CrossRef]
  34. Rugma, T.P.; Watts, A.; Vijayarajan, V.S.; Lakhera, S.K.; Neppolian, B. Synergistic hydrogen evolution activity of NiO/g-C3N4 photocatalysts under direct solar light irradiation. Mater. Lett. 2021, 302, 130292. [Google Scholar] [CrossRef]
  35. Tang, J.-y.; Guo, R.-t.; Zhou, W.-g.; Huang, C.-y.; Pan, W.-g. Ball-flower like NiO/g-C3N4 heterojunction for efficient visible light photocatalytic CO2 reduction. Appl. Catal. B Environ. 2018, 237, 802–810. [Google Scholar] [CrossRef]
  36. Li, S.; Tang, Y.; Wang, M.; Kang, J.; Jin, C.; Liu, J.; Li, Z.; Zhu, J. NiO/g-C3N4 2D/2D heterojunction catalyst as efficient peroxymonosulfate activators toward tetracycline degradation: Characterization, performance and mechanism. J. Alloys Compd. 2021, 880, 160547. [Google Scholar] [CrossRef]
  37. Sun, X.; Jiang, D.; Zhang, L.; Wang, W. Alkaline modified g-C3N4 photocatalyst for high selective oxide coupling of benzyl alcohol to benzoin. Appl. Catal. B Environ. 2018, 220, 553–560. [Google Scholar] [CrossRef]
  38. Zhang, Z.; Liu, K.; Feng, Z.; Bao, Y.; Dong, B. Hierarchical Sheet-on-Sheet ZnIn2S4/g-C3N4 Heterostructure with Highly Efficient Photocatalytic H2 production Based on Photoinduced Interfacial Charge Transfer. Sci. Rep. 2016, 6, 19221. [Google Scholar] [CrossRef]
  39. Bhunia, K.; Khilari, S.; Chandra, M.; Pradhan, D.; Kim, S.-J. Carbon nitride anchored NiO nanoparticles as robust catalyst for electrochemical oxygen evolution reaction. J. Alloys Compd. 2023, 935, 167842. [Google Scholar] [CrossRef]
  40. Dong, X.; Wang, H.; Li, X.; Fatehi, P.; Wang, S.; Wu, Q.; Liu, K.; Kong, F. In-situ sulfidation to fabricate NiSx modified g-C3N4/NiO composite for efficient photocatalytic hydrogen production under visible-light. Appl. Surf. Sci. 2023, 610, 155570. [Google Scholar] [CrossRef]
  41. Ding, C.; Zhu, Q.; Yang, B.; Petropoulos, E.; Xue, L.; Feng, Y.; He, S.; Yang, L. Efficient photocatalysis of tetracycline hydrochloride (TC-HCl) from pharmaceutical wastewater using AgCl/ZnO/g-C3N4 composite under visible light: Process and mechanisms. J. Environ. Sci. 2023, 126, 249–262. [Google Scholar] [CrossRef] [PubMed]
  42. Song, Z.; Hou, J.; Raguin, E.; Pedersen, A.; Eren, E.O.; Senokos, E.; Tarakina, N.V.; Giusto, P.; Antonietti, M. Triazine-Based Graphitic Carbon Nitride Thin Film as a Homogeneous Interphase for Lithium Storage. ACS Nano 2024, 18, 2066–2076. [Google Scholar] [CrossRef]
  43. Yang, H.; Zhang, A.; Ding, J.; Hu, R.; Gong, Y.; Li, X.; Chen, L.; Chen, P.; Tian, X. Amino modulation on the surface of graphitic carbon nitride for enhanced photocatalytic hydrogen production. Carbon 2024, 219, 118841. [Google Scholar] [CrossRef]
  44. Cai, J.; Huang, J.; Wang, S.; Iocozzia, J.; Sun, Z.; Sun, J.; Yang, Y.; Lai, Y.; Lin, Z. Crafting Mussel-Inspired Metal Nanoparticle-Decorated Ultrathin Graphitic Carbon Nitride for the Degradation of Chemical Pollutants and Production of Chemical Resources. Adv. Mater. 2019, 31, 1806314. [Google Scholar] [CrossRef] [PubMed]
  45. Wang, W.; Lv, B.; Tao, F. NiO/g-C3N4 composite for enhanced photocatalytic properties in the wastewater treatment. Environ. Sci. Pollut. 2023, 30, 25620–25634. [Google Scholar] [CrossRef]
  46. Wang, J.-C.; Wang, B.; Shi, W.; Qiao, X.; Yang, X.; Zhang, L.; Zhang, W.; Li, R.; Hou, Y. Natural-sunlight-driven synchronous degradation of 4-nitrphenol and rhodamine B over S-scheme heterojunction of α-Fe2O3 nanoparticles decorated CuBi2O4 rods. J. Environ. Chem. Eng. 2022, 10, 108565. [Google Scholar] [CrossRef]
  47. Zhang, Y.-Z.; Liang, C.; Feng, H.-P.; Liu, W. Nickel single atoms anchored on ultrathin carbon nitride for selective hydrogen peroxide generation with enhanced photocatalytic activity. Chem. Eng. J. 2022, 446, 137379. [Google Scholar] [CrossRef]
  48. Tian, J.; Feng, B.; Zhang, X.; Gu, K.; Pei, Y.; Qiao, M.; Zhang, J.; Zong, B. One-step nitrogen defect engineering of polymeric carbon nitride for visible light-driven photocatalytic O2 reduction to H2O2. J. Colloid Interface Sci. 2023, 634, 138–147. [Google Scholar] [CrossRef]
  49. Lu, W.-D.; Wang, D.; Zhao, Z.; Song, W.; Li, W.-C.; Lu, A.-H. Supported Boron Oxide Catalysts for Selective and Low-Temperature Oxidative Dehydrogenation of Propane. ACS Catal. 2019, 9, 8263–8270. [Google Scholar] [CrossRef]
  50. Cao, L.; Dai, P.; Zhu, L.; Yan, L.; Chen, R.; Liu, D.; Gu, X.; Li, L.; Xue, Q.; Zhao, X. Graphitic carbon nitride catalyzes selective oxidative dehydrogenation of propane. Appl. Catal. B Environ. 2020, 262, 118277. [Google Scholar] [CrossRef]
  51. Zhou, H.; Yi, X.; Hui, Y.; Wang, L.; Chen, W.; Qin, Y.; Wang, M.; Ma, J.; Chu, X.; Wang, Y.; et al. Isolated boron in zeolite for oxidative dehydrogenation of propane. Science 2021, 372, 76–80. [Google Scholar] [CrossRef] [PubMed]
  52. Cao, L.; Yan, P.; Wen, S.; Bao, W.; Jiang, Y.; Zhang, Q.; Yu, N.; Zhang, Y.; Cao, K.; Dai, P.; et al. Antiexfoliating h-BN⊃In2O3 Catalyst for Oxidative Dehydrogenation of Propane in a High-Temperature and Water-Rich Environment. J. Am. Chem. Soc. 2023, 145, 6184–6193. [Google Scholar] [CrossRef] [PubMed]
  53. Wang, T.-C.; Yin, J.-L.; Guo, X.-J.; Chen, Y.; Lang, W.-Z.; Guo, Y.-J. Modulating the crystallinity of boron nitride for propane oxidative dehydrogenation. J. Catal. 2021, 393, 149–158. [Google Scholar] [CrossRef]
  54. Jiang, C.; Chang, X.; Wang, X.; Zhao, Z.-J.; Gong, J. Enhanced C–H bond activation by tuning the local environment of surface lattice oxygen of MoO3. Chem. Sci. 2022, 13, 7468–7474. [Google Scholar] [CrossRef] [PubMed]
  55. Zhang, Y.; Zhao, Y.; Otroshchenko, T.; Lund, H.; Pohl, M.-M.; Rodemerck, U.; Linke, D.; Jiao, H.; Jiang, G.; Kondratenko, E.V. Control of coordinatively unsaturated Zr sites in ZrO2 for efficient C–H bond activation. Nat. Commun. 2018, 9, 3794. [Google Scholar] [CrossRef]
  56. Li, Y.; Han, B.; Bi, F.; Wu, Z.; Weng, X. One-Pot Synthesis of (CrMnFeCoNi)Ox High-Entropy Oxides for Efficient Catalytic Oxidation of Propane: A Promising Substitute for Noble Metal Catalysts. ACS Appl. Mater. Interfaces 2024, 16, 66108–66116. [Google Scholar] [CrossRef]
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Figure 1. (a) Synthetic scheme of NiO@CN. (b) XRD patterns of the prepared NiO@CN-600 and g-C3N4. (c) Nitrogen adsorption–desorption curves for NiO@CN-600; insets display the corresponding pore size distribution. (d) TGA curve of NiO@CN-600 under an air atmosphere.
Figure 1. (a) Synthetic scheme of NiO@CN. (b) XRD patterns of the prepared NiO@CN-600 and g-C3N4. (c) Nitrogen adsorption–desorption curves for NiO@CN-600; insets display the corresponding pore size distribution. (d) TGA curve of NiO@CN-600 under an air atmosphere.
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Figure 2. (a) Cross-sectional SEM image of NiO@CN-600. (b) Top-sectional SEM image of NiO@CN-600. (c) Elemental distribution images of the selected area (red box in Figure 2b). (d) TEM images of NiO@CN-600. (e) Particle size distribution of NiO nanoparticles. (f) HR-TEM image of NiO@CN-600.
Figure 2. (a) Cross-sectional SEM image of NiO@CN-600. (b) Top-sectional SEM image of NiO@CN-600. (c) Elemental distribution images of the selected area (red box in Figure 2b). (d) TEM images of NiO@CN-600. (e) Particle size distribution of NiO nanoparticles. (f) HR-TEM image of NiO@CN-600.
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Figure 3. (a) C 1s high-resolution spectrum of NiO@CN-600. (b) N 1s high-resolution spectrum of NiO@CN-600. (c) Ni 2p high-resolution spectrum of NiO@CN-600. (d) O 1s high-resolution spectrum of NiO@CN-600.
Figure 3. (a) C 1s high-resolution spectrum of NiO@CN-600. (b) N 1s high-resolution spectrum of NiO@CN-600. (c) Ni 2p high-resolution spectrum of NiO@CN-600. (d) O 1s high-resolution spectrum of NiO@CN-600.
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Figure 4. (a) UV-Vis DRS of g-C3N4. (b) Tauc plot of g-C3N4. (c) UPS spectrum of g-C3N4. (d) Schematic of band positions of NiO and g-C3N4.
Figure 4. (a) UV-Vis DRS of g-C3N4. (b) Tauc plot of g-C3N4. (c) UPS spectrum of g-C3N4. (d) Schematic of band positions of NiO and g-C3N4.
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Figure 5. (a) Propane conversion as a function of reaction temperature over NiO@CN-600. (b) Propene selectivity as a function of reaction temperature over NiO@CN-600. (c) Propene yield as a function of reaction temperature over NiO@CN-600. (d) Stability test of NiO@CN-600 for ODHP at 410 °C. (e) The carbon balance during the stability test of NiO@CN-600. (f) Comparison of the catalytic performance of NiO@CN-600 and other reported catalysts.
Figure 5. (a) Propane conversion as a function of reaction temperature over NiO@CN-600. (b) Propene selectivity as a function of reaction temperature over NiO@CN-600. (c) Propene yield as a function of reaction temperature over NiO@CN-600. (d) Stability test of NiO@CN-600 for ODHP at 410 °C. (e) The carbon balance during the stability test of NiO@CN-600. (f) Comparison of the catalytic performance of NiO@CN-600 and other reported catalysts.
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Figure 6. (a) XRD spectrum of NiO@CN-600 after stability test. (b) Nitrogen adsorption–desorption curves of NiO@CN-600 stability test, the inset shows the corresponding pore size distribution. (c,d) SEM images of NiO@CN-600 after stability test.
Figure 6. (a) XRD spectrum of NiO@CN-600 after stability test. (b) Nitrogen adsorption–desorption curves of NiO@CN-600 stability test, the inset shows the corresponding pore size distribution. (c,d) SEM images of NiO@CN-600 after stability test.
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Figure 7. (a) Comparison of propane conversion over g-C3N4 under thermal and photo-thermal catalytic conditions. (b) Comparison of propane conversion and propylene selectivity of NiO@CN-600 under different light intensities. (c) EPR spectra for NiO@CN-600 in light and dark conditions. (d) Schematic diagram illuminating the photo-thermal catalytic mechanism of NiO@CN-600.
Figure 7. (a) Comparison of propane conversion over g-C3N4 under thermal and photo-thermal catalytic conditions. (b) Comparison of propane conversion and propylene selectivity of NiO@CN-600 under different light intensities. (c) EPR spectra for NiO@CN-600 in light and dark conditions. (d) Schematic diagram illuminating the photo-thermal catalytic mechanism of NiO@CN-600.
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Dai, P.; Zhao, H.; Yang, D.; Zhao, Y.; Cheng, L.; Chen, H.; Jiang, D.; Cui, Y. Photo-Thermal Synergistic Catalytic Oxidative Dehydrogenation of Propane over NiO Nanoparticle-Decorated Graphitic Carbon Nitride. Catalysts 2025, 15, 919. https://doi.org/10.3390/catal15100919

AMA Style

Dai P, Zhao H, Yang D, Zhao Y, Cheng L, Chen H, Jiang D, Cui Y. Photo-Thermal Synergistic Catalytic Oxidative Dehydrogenation of Propane over NiO Nanoparticle-Decorated Graphitic Carbon Nitride. Catalysts. 2025; 15(10):919. https://doi.org/10.3390/catal15100919

Chicago/Turabian Style

Dai, Pengcheng, Hui Zhao, Dehong Yang, Yongxin Zhao, Longzhen Cheng, Huishan Chen, Dongzhi Jiang, and Yilong Cui. 2025. "Photo-Thermal Synergistic Catalytic Oxidative Dehydrogenation of Propane over NiO Nanoparticle-Decorated Graphitic Carbon Nitride" Catalysts 15, no. 10: 919. https://doi.org/10.3390/catal15100919

APA Style

Dai, P., Zhao, H., Yang, D., Zhao, Y., Cheng, L., Chen, H., Jiang, D., & Cui, Y. (2025). Photo-Thermal Synergistic Catalytic Oxidative Dehydrogenation of Propane over NiO Nanoparticle-Decorated Graphitic Carbon Nitride. Catalysts, 15(10), 919. https://doi.org/10.3390/catal15100919

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