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Article

Improving Stability and Colloidal Dispersity of CsPbBr3@SiO2 Nanoparticles Based on In-Situ Synthesis in Entropy Ligands Functionalized SiO2 Nanoreactor

by
Tianju Chen
†,
Peng Zhang
†,
Guoliang Chen
*,
Qi Yang
and
Feiming Li
*
College of Chemistry, Chemical Engineering and Environment, Minnan Normal University, Zhangzhou 363000, China
*
Authors to whom correspondence should be addressed.
†
Tianju Chen and Peng Zhang contributed equally to this work.
Crystals 2021, 11(10), 1165; https://doi.org/10.3390/cryst11101165
Submission received: 27 August 2021 / Revised: 9 September 2021 / Accepted: 11 September 2021 / Published: 24 September 2021
(This article belongs to the Section Materials for Energy Applications)
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Versions Notes

Abstract

:
Perovskite nanocrystals (PNCs) have witnessed unprecedented development in optoelectronic fields over the past few years. However, their intrinsic ionic structural instability still dramatically hinders their practical applications. Reliably improving the stability of PNCs while retaining their colloidal dispersity remains a grand challenge. Herein, we report a new strategy whereby CsPbBr3 nanoparticles are grown in situ in an entropy ligand-functionalized SiO2 nanoreactor. Consequently, the as-obtained CsPbBr3@SiO2 NPs show outstanding stability and colloidal dispersity in various non-polar solvents and have good solution processability, which are unattainable by conventional template-assisted methods.

1. Introduction

Since the pioneering work reported on the synthesis of cesium lead halide (CsPbX3, where X = Cl, Br, I) perovskite nanocrystals (PNCs) by Kovalenko et al. in 2015 [1], CsPbX3 PNCs have shown outstanding achievement in optoelectronic fields, including light-emitting diodes (LEDs), lasers, photodetectors, and solar cells [2,3,4,5]. These triumphant applications of PNCs can be attributed to their extraordinary optical properties including high photoluminescence quantum yield (PLQY), narrow spectra, short radiative lifetimes, and tunable band-edge emission, etc. [6,7,8,9]. Nevertheless, their intrinsic ionic structural instability makes them labile upon external disturbance, e.g., humidity, thermal treatment, and light illumination, impeding their practical applications [10,11,12,13,14]. Given this, chemical and structural strategies including surface modification, encapsulation approaches, component engineering, and heteratomic doping remain cutting-edge research and hot spots on improving the stability of PNCs [15,16,17,18].
Typically, encapsulation treatment has been proved to be an effective strategy to enhance the stability of PNCs against environmental interference, and simultaneously preserve bright emission, such as embedding PNCs into polymers, including block copolymer micelles [19,20], poly(lauryl methacrylate) [21,22], polystyrene [23,24,25], poly(vinylidene fluoride) [26,27], or inorganic matrices (MOFs [28,29], TiO2 [30], Al2O3 [31,32], Zeolite-Y [33,34], or SiO2 [35,36]). Among the various methods, the encapsulation of the SiO2 matrix is considered to be one of the most common and efficient approaches due to the excellent chemical stability and mechanical properties, as well as the low price and environmentally friendliness. However, the postcoating of SiO2 easily causes multiple PNCs to grow randomly on the shells and generate uneven or large aggregates on account of the silane hydrolysis that is difficult to control. Then, to make matters worse, the water and alcohols derived from the by-product of silane hydrolysis can decompose the PNCs. Conversely, in-situ crystallized PNCs under the nanoconfinement effect of porous templates can limit crystal growth to a specific size range and prevents secondary decomposition. However, it is worth noting that nanotemplates often tend towards aggregation in nonpolar solvents owing to their physical adsorption, which actually works against their solution processability [37]. The restriction incurs difficulties in coupling them with conventional optoelectronics platforms. Overall, it remains highly desirable for the PNCs to overcome the stability issues while maintaining excellent solution processability at the nanoscale range.
Recently, entropic ligands control has been proved to be an effective strategy for improving the monodispersity of colloidal nanocrystals [38,39]. For instance, by combining two distinguishable chain-length n-alkanoate, the solubility of the resulting colloidal nanocrystals can increase up to about six orders of magnitude, because the C–C σ-bond intramolecular entropy in the solution substantially reduces the dissolution enthalpy and facilitates its dispersion. Inspired by such entropy–enthalpy competition, herein we introduced a modified template-assisted strategy with entropy ligands for the synthesis of CsPbBr3 nanocomposites, in which hollow siliceous nanospheres (HSNSs) templates with a high entropy surface are constructed through grafting mixed ligands (ML) with distinguishable long-chain ligands (oleoyl chloride, OCl) and short-chain bendritic ligands (trimethylbromosilane, TMBS). HSNSs-ML would serve as a nanoreactor for in situ growing of CsPbBr3 PNCs to fabricate CsPbBr3@HSNSs-ML. The resulting CsPbBr3@HSNSs-ML nanocomposites have better stability and colloidal dispersity in comparison with either of the pure-ligand counterparts, which is favorable for solution processability. Furthermore, the other PNCs, including organic–inorganic PNCs and doped PNCs, could also be fabricated based on this method. The generalization of this strategy means it has good prospects in the field of PNC synthesis.

2. Materials and Methods

2.1. Materials

Dimethoxydimethylsilane (DMDMS), tetraethoxysilane (TEOS), hydrochloric acid (HCl, 37% in water), 1,3,5-trimethylbenzene (TMB), dimethyl sulfoxide with molecular sieves (DMSO, 99.8%), lead bromide (PbBr2, 98.0%), cesium bromide (CsBr, 99.9%), trimethylbromosilane (TMBS, 97%), oleoyl chloride (OCl, 97%), triethylamine (TEA, 99.5%), dichloromethane (DCM, 99.5%), cyclohexane (CYH, 99.7%), and ethanol (EtOH, 99.8%) were acquired from Aladdin. Pluronic F108 was purchased from Sigma-Aldrich. The solutions were prepared with Millipore water (18 MΩ cm), and all the chemical reagents were used as received without further purification.

2.2. Experimental Section

Synthesis of the Hollow Siliceous Nanospheres (HSNSs). The HSNSs were prepared according to the previously reported method [40]. In typical synthesis, 1.0 g Pluronic F108, 5.0 mL HCl, and 25 mL H2O were mixed in a 50-mL glass vial and stirred vigorously to yield a homogeneous solution. Subsequently, 0.8 g TMB was introduced to the solution and was continuously stirred (1000 rpm) at 28 °C for 3 h. Then, 1.0 g TEOS was dropwise added to the system with an addition rate of 0.1 mL min−1 for 6 h, and 0.4 g DMDMS was dropwise added with a rate of 0.1 mL min−1 for 3 days. The resulting solvent was removed by rotary evaporation at 80 °C. The residual was refluxed twice in a 30 mL ethanol-HCl (29:1, v/v) solution for 12 h to remove the surfactant. The solid product was collected by centrifugation (10,000 rpm, 15 min) and repeatedly washed with ethanol to completely remove the Pluronic F108 and HCl. Finally, HSNSs were obtained by vacuum desiccation overnight at 60 °C.
Synthesis of the HSNSs-Grafted (HSNSs-OAe, HSNSs-TMe and HSNSs-ML). The HSNSs-Grafted were prepared via a nucleophilic substitution reaction at the silanol surface of the template. Before use, the HSNSs were dried overnight at 80 °C under vacuum. Then, 20.0 mg HSNSs, 3.0 mL DCM, and 90 μL TEA were mixed in a 10-mL glass vial with 60 μL of TMBS, or with a similar amount of OCl, and continuously stirred (1000 rpm) for 24 h. The solid product was repeatedly washed with ethanol by ultrasound and collected by centrifugation (10,000 rpm, 15 min). Afterward, HSNSs-TMe or HSNSs-OCl were obtained by vacuum desiccation overnight at 60 °C. For the synthesis of HSNSs-ML, OCl was first reacted for 12 h, and then TMBS was added for another 12 h. Other procedures were performed in the same way as above.
Synthesis of CsPbBr3@HSNSs and CsPbBr3@HSNSs-Grafted NPs (including HSNSs-ML, HSNSs-Ocl and HSNSs-Tme). The CsPbBr3@HSNSs NPs were prepared following a template-assisted technique. Typically, the CsPbBr3 precursor solution (0.1 M) was prepared by dissolving 0.1 mmol CsBr and 0.1 mmol PbBr2 in 1.0 mL of DMSO. Subsequently, 50 μL of the precursor solution was thoroughly mixed with 20 mg of HSNSs and treated with sonication for 10 min. After the impregnation, the excess solution was removed by damping with filter paper. The as-obtained powder was sandwiched between two glass slides and heated up to 60 °C in a vacuum oven. Afterwards, the powder was allowed to cool to room temperature in the air. Finally, the product was collected and sealed in a centrifuge tube immediately. The synthesis of CsPbBr3@HSNSs-Grafted NPs was performed in an analogous way, except that the template was changed with a similar mass of HSNSs-Grafted.

2.3. Sample Characterization

Fluorescence (PL) emission spectra were collected by a Gary Eclipse (Agilent, Santa Clara, CA, USA) spectrophotometer. The PL lifetime and absolute PL quantum yields were measured using an FLS 980 (Edinburgh, Livingston, UK) spectrometer with a nanosecond flash lamp. The Specord 200 plus (Analytik Jena, Jena, Germany) was employed to obtain the UV−Vis absorption spectra in transmission mode. The morphologies were investigated by Tecnai-G2-F30 (FEI, Hillsboro, OR, USA) transmission electron microscope instruments at 200 kV. Fourier-transform infrared spectroscopy (FTIR) spectra of the compounds are recorded on Nicolet iS 10 (Thermo Fisher, Waltham, MA, USA) in the range of 500 to 4000 cm−1. X-ray diffraction (XRD) was obtained with an Ultima IV diffractometer (Rigaku, Tokyo, Japan) with Cu Kα (1.79 Å) over the 2θ range of 10–60°.

3. Results and Discussion

The synthesis of CsPbBr3@HSNSs-ML with a high entropy surface is illustrated in Figure 1. First, the HSNSs are synthesized via the acid catalytic hydrolysis of tetraethyl orthosilicate (TEOS) and Dimethoxydimethylsilane (DMDMS) with the aid of a surfactant. Then, long-chain ligands OCl and short-chain ligands TMBS were grafted on the silanol surface of HSNSs by stepwise reaction to form the HSNSs-ML nanoreactor. Subsequently, the CsPbBr3 precursor solution was ultrasonically immersed into the cavity of the HSNSs-ML nanoreactor by capillary forces, followed by vacuum drying, leading to in situ crystallization of CsPbBr3@HSNSs-ML nanocomposites. Consequently, as a benefit of the high entropy surface of HSNSs-ML, the CsPbBr3@HSNSs-ML shows good colloidal dispersity and solution processability, which could be easily applied to fabricate a CsPbBr3@HSNSs-ML polystyrene film without any aggregation; in contrast, the CsPbBr3@HSNSs NPs grown within unmodified HSNSs show obvious aggregation as illustrated in Figure 1.
TEM images confirm that the as-synthesized HSNSs-ML is an exclusively hollow structure with uniform particle size distribution. An average diameter of 15.5 ± 1.1 nm is collected by directly measuring the diameters of 80 individual HSNSs-ML from the TEM images (Figure 2a,b). Besides, the pore size distributions of HSNSs and HSNSs-ML were analyed by the Barrett–Joyner–Halenda (BJH) method and results are shown in Figure 2c,d, whereby both of them demonstrated uniform pore size distributions centered at 3.3 nm and 8.6 nm, and 3.2 nm and 8.4 nm, corresponding to the surfactant-derived mesopores and center cavity, respectively. The reduced pore size distributions in HSNSs-ML are attributed to the steric hindrance of grafted alkane. Besides, HSNSs and HSNSs-ML displayed typical type-IV N2 adsorption isotherms with obvious hysteresis and capillary condensation between the relative pressure of 0.4 and 1 (illustration in Figure 2c,d), indicating the presence of a regular pore structure.
Compared with HSNSs-ML, TEM images of CsPbBr3@HSNSs-ML NPs showed that the overall morphology and average size (15.8 ± 1.1 nm) are nearly unchanged except that the cavities disappeared (Figure 3a,b), indicating the CsPbBr3 PNCs are in situ growing in the pores. The as-synthesized CsPbBr3@HSNSs-ML emits blue-green photoluminescence (PL) under the excitation of 365 nm UV light, showing a sharp PL peak at 500 nm with a full width at half-maximum (FWHM) of 25 nm (Figure 3c). The CsPbBr3@HSNSs-ML NPs’ platelet surface demonstrates high hydrophobicity with a water contact angle of 135°, which is attributed to the water-tolerance organic layer (inset in Figure 3c). In addition, as shown in Figure 3d, the X-ray diffraction (XRD) patterns of the CsPbBr3@HSNSs-ML NPs display weak yet discernible diffraction peaks at 15.1°, 21.3°, 30.4°, 34.1°, 37.5°, and 43.5°, which correspond to the (100), (110), (200), (210), (211), and (220) crystal planes of the cubic phase CsPbBr3 (standard card, ICSD#01-075-0412), respectively. The weak diffraction peaks can be ascribed to the relatively small amount of CsPbBr3 and the high content of amorphous SiO2 in the CsPbBr3@HSNSs-ML. Furthermore, the broad peak in the range between 15° and 30° can be attributed to the existence of amorphous SiO2.
To verify whether the ligands are grafted on the HSNSs surface or not, Fourier-transform infrared spectroscopy (FTIR) spectra of HSNSs and HSNSs-Grafted (including HSNSs-ML, HSNSs-OCl, and HSNSs-TMe) are displayed in Figure 4a, in which we can observe that the asymmetric vibration and symmetric stretching vibration of Si-O-Si appear at about 1090 and 800 cm−1, demonstrating the formation of cross-linked SiO2. Nonetheless, it is worth mentioning that all the FTIR results show a nearly identical signal, which may be ascribed to the organic chain signal overlayed by the strong silica signal. Therefore, we further characterized the 1H NMR spectrum to determine the surface condition of HSNSs-grafted. As shown in Figure 4b, the chemical shift of –CH=CH– at about 5.57 ppm in HSNSs-OCl and HSNSs-ML indicates the existence of OCl. In addition, the signal of the chemical shift of -Si-CH3 at about −0.04 ppm in HSNSs-TMe and HSNSs-ML shows significant enhancement, indicating that TMBS was successfully grafted on the silanol interface. Moreover, the same chemical shifts of -Si-CH3 appearing in all the templates stem from the capped silica donated by DMDMs.
The thermodynamic model states that the stability of a colloidal solution is due to the C−C σ-bond rotation/bending vibration entropy, rather than the stereoscopic barrier of the alkane chain, as traditionally believed [39]. In order to verify the solution properties regulated by entropy coefficients, control experiments were performed. First, the dispersity of the obtained CsPbBr3 PNCs nanocrystals based on in-situ synthesis in an entropy ligand-functionalized SiO2 nanoreactor was fully investigated, which was evaluated via observing their sedimentation velocity for different durations under an ultraviolet lamp. First, the CsPbBr3@HSNSs, CsPbBr3@HSNSs-pure, and CsPbBr3@HSNSs-ML were individually mixed within cyclohexane with the same amount and sonicated for 15 min to yield a homogeneous solution. As illustrated in Figure 5a, the results showed that the sedimentation velocity is in the order of CsPbBr3@HSNSs > CsPbBr3@HSNSs-OCl > CsPbBr3@HSNSs-TMe > CsPbBr3@HSNSs-ML, demonstrating the dispersity of CsPbBr3@HSNSs could be feasibly improved via mix ligands grafting. The dispersity of CsPbBr3@HSNSs-ML reached the maximum when 40 uL OCl and TMe were used. Moreover, as shown in Figure 5c, the obtained CsPbBr3@HSNSs-ML could be well dispersed in a variety of non-polar solvents, including N-hexane, cyclohexane, ethyl acetate, and toluene, which is beneficial to solution processability. This result indicates the excellent properties of the entropic template and facilitates their further development in the relevant fields.
Furthermore, the optical properties of CsPbBr3@HSNSs-ML were also investigated. Due to the quantum confinement, the optical properties of the grown CsPbBr3 PNCs were dependent on the cavity of HSNSs. Compared with the CsPbBr3@HSNSs, we found CsPbBr3@HSNSs-ML blue shifted as illustrated in Figure 6a, though the cavity diameter of the HSNSs-ML remained almost the same after ligand grafting (about 8.4 nm). The reason might be that the TMBS penetrated into the mesopores, reacted with the silanol interface of HSNSs, and compressed the growth and crystallinity of the PNC core. As verification, the emission spectrum of CsPbBr3@HSNSs-TMe shows a similar blue-shift trend, while that of CsPbBr3@HSNSs-OCl has little change (Figure 6b,c). This is also illustrated by the weakened diffraction peak signals on the corresponding XRD patterns after ligand TMBS grafting (Figure 6d,e). However, the mechanism behind these still needs to be further explored.
The stability of the CsPbBr3@HSNSs and CsPbBr3@HSNSs-Grafted against the detrimental effects of heat and light irradiation was tested and compared with conventional hot-injected CsPbBr3 PNCs. We fixed the concentrations of all the CsPbBr3 PNCs by controlling the absorption intensity at the same value (at about 0.1) in their intrinsic absorption wavelength (335 nm). As a result, thermal testing shows that the remnant PL intensities of CsPbBr3@HSNSs NPs and CsPbBr3@HSNSs-ML remain over 70% after repeated heating cycling at 100 °C (Figure 7a). For comparison, the CsPbBr3 PNCs solution was quenched rapidly within 5 cycles. Furthermore, the photostability test results show that CsPbBr3@HSNSs and CsPbBr3@HSNSs-ML still remain over 70% relative PL after continuous irradiation for 14 h, while the CsPbBr3 PNCs had almost no performance (Figure 7b). The result suggests that the decomposition is greatly suppressed by SiO2 shells.
Finally, to further investigate the generality of this strategy, we use HSNSs-ML for the synthesis of the other PNCs systems, including Mn-doped systems and organic–inorganic hybridized systems. (Figure 8). The experiments show that the majority of PNCs, especially organic–inorganic hybrid PNCs, have good dispersity and optical properties.

4. Conclusions

In conclusion, the CsPbBr3@HSNSs-ML NPs have been successfully prepared by a ligand-grafted template-assisted strategy, where the templates (namely HSNSs) are functionalized by entropy ligands. As a result, the products show outstanding dispersion in various non-polar solvents. The mixed ligands with distinguishable hydrocarbon chain lengths are selected to replace the entropy ligand for verifying solution properties regulated by entropy coefficients. In addition, with the double protection of SiO2 and the moisture-tolerant organic layer, the NPs show better water resistance and higher photostability and thermal stability. Meanwhile, this work overcomes the inherent limitation of template-assisted methods in solution processability and provides a new model for monodisperse PNCs with a core/shell structure.

Author Contributions

Conceptualization, F.L.; methodology, T.C. and P.Z.; software, T.C.; validation, T.C. and Q.Y.; formal analysis, T.C. and Q.Y.; investigation, T.C. and P.Z.; data curation, T.C.; writing—original draft preparation, T.C. and P.Z.; writing—review and editing, G.C. and F.L.; visualization, Q.Y.; supervision, F.L.; project administration, F.L.; funding acquisition, G.C. and F.L. All authors have read and agreed to the published version of the manuscript.

Funding

National Natural Science Foundation of China (No. 22004055), Natural Science Foundation of Fujian Province of China (2020J05165).

Acknowledgments

We gratefully acknowledge the financial support from the National Natural Science Foundation of China (No. 22004055), Natural Science Foundation of Fujian Province of China (2020J05165).

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Protesescu, L.; Yakunin, S.; Bodnarchuk, M.I.; Krieg, F.; Caputo, R.; Hendon, C.H.; Yang, R.X.; Walsh, A.; Kovalenko, M.V. Nanocrystals of cesium lead halide perovskites (CsPbX3, X = Cl, Br, and I): Novel optoelectronic materials showing bright emission with wide color gamut. Nano Lett. 2015, 15, 3692–3696. [Google Scholar] [CrossRef] [Green Version]
  2. Jeon, N.J.; Na, H.; Jung, E.H.; Yang, T.Y.; Lee, Y.G.; Kim, G.; Shin, H.W.; Seok, S.I.; Lee, J.; Seo, J. A fluorene-terminated hole transporting material for highly efficient and stable perovskite solar cells. Nat. Energy 2018, 3, 682–689. [Google Scholar] [CrossRef]
  3. Zhou, Q.; Bai, Z.; Lu, W.G.; Wang, Y.; Zou, B.; Zhong, H. In situ fabrication of halide perovskite nanocrystal-embedded polymer composite films with enhanced photoluminescence for display backlights. Adv. Mater. 2016, 28, 9163–9168. [Google Scholar] [CrossRef]
  4. Lai, Q.; Zhu, L.; Pang, Y.; Xu, L.; Chen, J.; Ren, Z.; Luo, J.; Wang, L.; Chen, L.; Han, K.; et al. Piezo-phototronic effect enhanced photodetector based on CH3NH3PbI3 single crystals. ACS Nano 2018, 12, 10501–10508. [Google Scholar] [CrossRef]
  5. Wang, J.; Da, P.; Zhang, Z.; Luo, S.; Liao, L.; Sun, Z.; Shen, X.; Wu, S.; Zheng, G.; Chen, Z. Lasing from lead halide perovskite semiconductor microcavity system. Nanoscale 2018, 10, 10371–10376. [Google Scholar] [CrossRef] [PubMed]
  6. Zhang, F.; Zhong, H.Z.; Chen, C.; Wu, X.G.; Hu, X.M.; Huang, H.L.; Han, J.B.; Zou, B.S.; Dong, Y.P. Brightly luminescent and color-tunable colloidal CH3NH3PbX3 (X = Br, I, Cl) quantum dots: Potential alternatives for display technology. ACS Nano 2015, 9, 4533–4542. [Google Scholar] [CrossRef] [PubMed]
  7. Prashant, K.; Ganesh, N.; Narayan, K.S. Electrospun fibers containing emissive hybrid perovskite quantum dots. ACS Appl. Mater. Interfaces 2019, 11, 24468–24477. [Google Scholar] [CrossRef]
  8. Geng, C.; Xu, S.; Zhong, H.Z.; Andrey, L.R.; Bi, W.G. Aqueous synthesis of methylammonium lead halide perovskite nanocrystals. Angew. Chem. Int. Ed. 2018, 130, 9798–9802. [Google Scholar] [CrossRef]
  9. Wang, L.L.; Nicholas, E.W.; Edward, W.M.; John, P.O.; Dugan, H.; Ryan, E.W.; Philippe, G.S.; Gregory, S.E. Scalable ligand-mediated transport synthesis of organic-inorganic hybrid perovskite nanocrystals with resolved electronic structure and ultrafast dynamics. ACS Nano 2017, 11, 2689–2696. [Google Scholar] [CrossRef]
  10. Dang, Z.Y.; Shamsi, J.; Palazon, F.; Imran, M.; Akkerman, Q.A.; Park, S.; Bertoni, G.; Prato, M.; Brescia, R.; Manna, L. In situ transmission electron microscopy study of electron beam-induced transformations in colloidal cesium lead halide perovskite nanocrystals. ACS Nano 2017, 11, 2124–2132. [Google Scholar] [CrossRef] [Green Version]
  11. Huang, S.; Li, Z.; Kong, L.; Zhu, N.; Shan, A.; Li, L. Enhancing the stability of CH3NH3PbBr3 quantum dots by embedding in silica spheres derived from tetramethyl orthosilicate in “waterless” toluene. J. Am. Chem. Soc. 2016, 138, 5749–5752. [Google Scholar] [CrossRef]
  12. Luo, B.; Pu, Y.C.; Lindley, S.A.; Yang, Y.; Lu, L.; Li, Y.; Li, X.; Zhang, J.Z. Organolead halide perovskite nanocrystals: Branched capping ligands control crystal size and stability. Angew. Chem. Int. Ed. 2016, 55, 8864–8868. [Google Scholar] [CrossRef] [Green Version]
  13. Zhang, H.; Wang, X.; Liao, Q.; Xu, Z.; Li, H.; Zheng, L.; Fu, H. Embedding perovskite nanocrystals into a polymer matrix for tunable luminescence probes in cell imaging. Adv. Funct. Mater. 2017, 27, 1604382. [Google Scholar] [CrossRef]
  14. Chen, L.; Tan, Y.Y.; Chen, Z.X.; Wang, T.; Hu, S.; Nan, Z.A.; Xie, L.Q.; Hui, Y.; Huang, J.X.; Zhan, C.; et al. Toward long-term stability: Single-crystal alloys of cesium-containing mixed cation and mixed halide perovskite. J. Am. Chem. Soc. 2019, 141, 1665–1671. [Google Scholar] [CrossRef]
  15. Yang, D.; Cao, M.; Zhong, Q.; Li, P.; Zhang, X.; Zhang, Q. All-inorganic cesium lead halide perovskite nanocrystals: Synthesis, surface engineering and applications. J. Mater. Chem. C 2019, 7, 757–789. [Google Scholar] [CrossRef]
  16. Yang, D.; Li, X.; Zeng, H. Surface chemistry of all inorganic halide perovskite nanocrystals: Passivation mechanism and stability. Adv. Mater. Interfaces 2018, 5, 1701662. [Google Scholar] [CrossRef] [Green Version]
  17. Liu, M.N.; Ali-Löytty, H.; Hiltunen, A.; Sarlin, E.; Qudsia, S.; Smått, J.H.; Valden, M.; Vivo, P. Manganese doping promotes the synthesis of bismuth-based perovskite nanocrystals while tuning their band structures. Small 2021, 17, 2100101. [Google Scholar] [CrossRef] [PubMed]
  18. Liu, M.N.; Pasanen, H.; Ali-Löytty, H.; Hiltunen, A.; Lahtonen, K.; Qudsia, S.; Smått, J.H.; Valden, M.; Tkachenko, N.V.; Vivo, P. B-site co-alloying with germanium improves the efficiency and stability of all-inorganic tin-Based perovskite nanocrystal solar cells. Angew. Chem. Int. Ed. 2020, 132, 22117–22125. [Google Scholar] [CrossRef] [PubMed]
  19. Hou, S.C.; Guo, Y.Z.; Tang, Y.G.; Quan, Q.M. Synthesis and stabilization of colloidal perovskite nanocrystals by multidentate polymer micelles. ACS Appl. Mater. Interfaces 2017, 9, 18417–18422. [Google Scholar] [CrossRef] [PubMed]
  20. Huang, Y.J.; Chen, H.C.; Lin, H.-K.; Wei, K.H.; Su, Y.W. Block copolymer-tuned fullerene electron transport layer enhances the efficiency of perovskite photovoltaics. ACS Appl. Mater. Interfaces 2016, 8, 24603–24611. [Google Scholar] [CrossRef]
  21. Raja, S.N.; Bekenstein, Y.; Koc, M.A.; Fischer, S.; Zhang, D.; Lin, L.; Ritchie, R.O.; Yang, P.; Alivisatos, A.P. Encapsulation of perovskite nanocrystals into macroscale polymer matrices: Enhanced stability and polarization. ACS Appl. Mater. Interfaces 2016, 8, 35523–35533. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  22. Zhao, H.; Benetti, D.; Tong, X.; Zhang, H.; Zhou, Y.; Liu, G.; Ma, D.; Sun, S.; Wang, Z.M.; Wang, Y.; et al. Efficient and stable tandem luminescent solar concentrators based on carbon dots and perovskite quantum dots. Nano Energy 2018, 50, 756–765. [Google Scholar] [CrossRef]
  23. Cai, Y.; Wang, L.; Zhou, T.; Zheng, P.; Li, Y.; Xie, R.J. Improved stability of CsPbBr3 perovskite quantum dots achieved by suppressing interligand proton transfer and applying a polystyrene coating. Nanoscale 2018, 10, 21441–21450. [Google Scholar] [CrossRef] [PubMed]
  24. Wei, Y.; Deng, X.; Xie, Z.; Cai, X.; Liang, S.; Ma, P.; Hou, Z.; Cheng, Z.; Lin, J. Enhancing the stability of perovskite quantum dots by encapsulation in crosslinked polystyrene beads via a swelling-shrinking strategy toward superior water resistance. Adv. Funct. Mater. 2017, 27, 1703535. [Google Scholar] [CrossRef]
  25. Liang, X.; Chen, M.; Wang, Q.; Guo, S.; Yang, H. Ethanol-precipitable, silica-passivated perovskite nanocrystals incorporated into polystyrene microspheres for long-term storage and reusage. Angew. Chem. Int. Ed. 2019, 131, 2825–2829. [Google Scholar] [CrossRef]
  26. Ding, R.; Zhang, X.; Chen, G.; Wang, H.; Kishor, R.; Xiao, J.; Gao, F.; Zeng, K.; Chen, X.; Sun, X.W.; et al. High-performance piezoelectric nanogenerators composed of formamidinium lead halide perovskite nanoparticles and poly(vinylidene fluoride). Nano Energy 2017, 37, 126–135. [Google Scholar] [CrossRef]
  27. Sultana, A.; Sadhukhan, P.; Alam, M.M.; Das, S.; Middya, T.R.; Mandal, D. Organo-lead halide perovskite induced electroactive β-phase in porous PVDF films: An excellent material for photoactive piezoelectric energy harvester and photodetector. ACS Appl. Mater. Interfaces 2018, 10, 4121–4130. [Google Scholar] [CrossRef]
  28. Ryu, U.; Jee, S.; Park, J.S.; Han, I.K.; Lee, J.H.; Park, M.; Kyung, M.C. Nanocrystalline titanium metal-organic frameworks for highly efficient and flexible perovskite solar cells. ACS Nano 2018, 12, 4968–4975. [Google Scholar] [CrossRef]
  29. Rambabu, D.; Bhattacharyya, S.; Tarandeep, S.; Chakravarthy, M.L.; Tapas, K.M. Stabilization of MAPbBr3 perovskite quantum dots on perovskite MOFs by a one-step mechanochemical synthesis. Inorg. Chem. 2020, 59, 1436–1443. [Google Scholar] [CrossRef]
  30. Li, Z.J.; Hofman, E.; Li, J.; Davis, A.H.; Tung, C.H.; Wu, L.Z.; Zheng, W. Photoelectrochemically active and environmentally stable CsPbBr3/TiO2 core/shell nanocrystals. Adv. Funct. Mater. 2018, 28, 1–7. [Google Scholar] [CrossRef]
  31. Dibyashree, K.; Lotte, H.; Valerio, Z.; Vincent, V.; Marcel, A.V.; Wilhelmus, M.M.K.; Mariadriana, C. Chemical analysis of the interface between hybrid organic-inorganic perovskite and atomic layer deposited Al2O3. ACS Appl. Mater. Interfaces 2019, 11, 5526–5535. [Google Scholar] [CrossRef] [Green Version]
  32. Yu, H.; Xu, X.; Liu, H.; Wan, Y.; Cheng, X.; Chen, J.; Ye, Y.; Dai, L. Waterproof cesium lead bromide perovskite lasers and their applications in solution. ACS Nano 2020, 14, 552–558. [Google Scholar] [CrossRef] [PubMed]
  33. Sun, J.Y.; Rabou, F.T.; Yang, X.F.; Huang, X.P. Facile two-step synthesis of all-inorganic perovskite CsPbX3 (X = Cl, Br, and I) zeolite-Y composite phosphors for potential backlight display application. Adv. Funct. Mater. 2017, 27, 1704371. [Google Scholar] [CrossRef]
  34. Ye, S.; Sun, J.; Han, Y.; Zhou, Y.; Zhang, Q. Confining Mn2+-doped lead halide perovskite in zeolite-Y as ultrastable orange-red phosphor composites for white light-emitting diodes. ACS Appl. Mater. Interfaces 2018, 10, 24656–24664. [Google Scholar] [CrossRef] [PubMed]
  35. Zhong, Q.; Cao, M.; Hu, H.; Yang, D.; Chen, M.; Li, P.; Wu, L.; Zhang, Q. One-pot synthesis of highly stable CsPbBr3@SiO2 core-shell nanoparticles. ACS Nano 2018, 12, 8579–8587. [Google Scholar] [CrossRef]
  36. Dirin, D.N.; Protesescu, L.; Trummer, D.; Kochetygov, I.V.; Yakunin, S.; Krumeich, F.; Stadie, N.P.; Kovalenko, M.V. Harnessing defect-tolerance at the nanoscale: Highly luminescent lead halide perovskite nanocrystals in mesoporous silica matrixes. Nano Lett. 2016, 16, 5866–5874. [Google Scholar] [CrossRef] [PubMed]
  37. He, Y.J.; Yoon, Y.J.; Harn, Y.W.; Gill, V.B.M.; Liang, S.; Lin, C.H.; Tsukruk, V.V.; Thadhani, N.; Kang, Z.T.; Lin, Z.Q. Unconventional route to dual-shelled organolead halide perovskite nanocrystals with controlled dimensions, surface chemistry, and stabilities. Sci. Adv. 2019, 5, eaax4424. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  38. Pang, F.Z.; Zhang, J.; Cao, W.C.; Kong, X.Q.; Peng, X.G. Partitioning surface ligands on nanocrystals for maximal solubility. Nat. Commun. 2019, 10, 2454. [Google Scholar] [CrossRef] [Green Version]
  39. Yang, Y.; Qin, H.Y.; Peng, X.G. Intramolecular entropy and size-dependent solution properties of nanocrystal-ligands complexes. Nano Lett. 2016, 16, 2127–2132. [Google Scholar] [CrossRef] [PubMed]
  40. Huang, Y.P.; Li, F.M.; Qiu, L.H.; Lin, F.Y.; Lai, Z.W.; Wang, S.Y.; Lin, L.H.; Zhu, Y.M.; Wang, Y.; Jiang, Y.Q.; et al. Enhancing the stability of CH3NH3PbBr3 nanoparticles using double hydrophobic shells of SiO2 and poly(vinylidene fluoride). ACS Appl. Mater. Interfaces 2019, 11, 26384–26391. [Google Scholar] [CrossRef]
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Figure 1. Schematic depiction of two pathways to construct template-assisted CsPbBr3 nanoparticles and the comparison of their solution properties in cyclohexane.
Figure 1. Schematic depiction of two pathways to construct template-assisted CsPbBr3 nanoparticles and the comparison of their solution properties in cyclohexane.
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Figure 2. (a) Representative TEM images of the as-prepared HSNSs-ML; (b) the diameter distribution histogram of HSNSs-ML by calculating 80 individual nanospheres; (c,d) the size distribution of the cavity of HSNSs and HSNSs-ML, respectively. Insets in (c,d) show their relevant N2 adsorption-desorption isotherms.
Figure 2. (a) Representative TEM images of the as-prepared HSNSs-ML; (b) the diameter distribution histogram of HSNSs-ML by calculating 80 individual nanospheres; (c,d) the size distribution of the cavity of HSNSs and HSNSs-ML, respectively. Insets in (c,d) show their relevant N2 adsorption-desorption isotherms.
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Figure 3. (a) Representative TEM images of the as-prepared CsPbBr3@HSNSs-ML NPs; (b) the diameter distribution histogram of CsPbBr3@HSNSs-ML NPs by calculating 80 individual nanospheres; (c) absorption and PL spectra of the CsPbBr3@HSNSs-ML NPs; insets in (c) show the water CA (bottom); (d) XRD pattern of CsPbBr3@HSNSs-ML.
Figure 3. (a) Representative TEM images of the as-prepared CsPbBr3@HSNSs-ML NPs; (b) the diameter distribution histogram of CsPbBr3@HSNSs-ML NPs by calculating 80 individual nanospheres; (c) absorption and PL spectra of the CsPbBr3@HSNSs-ML NPs; insets in (c) show the water CA (bottom); (d) XRD pattern of CsPbBr3@HSNSs-ML.
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Figure 4. (a) FTIR spectra; (b) 1H NMR spectrum of CsPbBr3@HSNSs NPs and CsPbBr3@HSNSs-Grafted NPs.
Figure 4. (a) FTIR spectra; (b) 1H NMR spectrum of CsPbBr3@HSNSs NPs and CsPbBr3@HSNSs-Grafted NPs.
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Figure 5. (a) Photos of CsPbBr3@HSNSs-Grafted during different static time periods under a 365 nm UV lamp; (b) settlement velocity of CsPbBr3@HSNSs-Grafted when HSNSs are grafted by different ligand dosages; (c) dispersive capacity of CsPbBr3@HSNSs-ML in a variety of non-polar solvents.
Figure 5. (a) Photos of CsPbBr3@HSNSs-Grafted during different static time periods under a 365 nm UV lamp; (b) settlement velocity of CsPbBr3@HSNSs-Grafted when HSNSs are grafted by different ligand dosages; (c) dispersive capacity of CsPbBr3@HSNSs-ML in a variety of non-polar solvents.
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Figure 6. (a–c) The PL spectrum of diverse CsPbBr3@HSNSs-Grafted and (d–f) their corresponding XRD spectra.
Figure 6. (a–c) The PL spectrum of diverse CsPbBr3@HSNSs-Grafted and (d–f) their corresponding XRD spectra.
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Figure 7. Variations of the PL intensity for CsPbBr3 NCs, CsPbBr3@HSNSs, and CsPbBr3@HSNSs-ML under (a) a high temperature environment and (b) UV irradiation.
Figure 7. Variations of the PL intensity for CsPbBr3 NCs, CsPbBr3@HSNSs, and CsPbBr3@HSNSs-ML under (a) a high temperature environment and (b) UV irradiation.
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Figure 8. Absorption and PL emission spectra of diverse template-assisted PNCs using purpose HSNSs-ML; illustrations are their photographs under a 365 nm UV lamp.
Figure 8. Absorption and PL emission spectra of diverse template-assisted PNCs using purpose HSNSs-ML; illustrations are their photographs under a 365 nm UV lamp.
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Chen, T.; Zhang, P.; Chen, G.; Yang, Q.; Li, F. Improving Stability and Colloidal Dispersity of CsPbBr3@SiO2 Nanoparticles Based on In-Situ Synthesis in Entropy Ligands Functionalized SiO2 Nanoreactor. Crystals 2021, 11, 1165. https://doi.org/10.3390/cryst11101165

AMA Style

Chen T, Zhang P, Chen G, Yang Q, Li F. Improving Stability and Colloidal Dispersity of CsPbBr3@SiO2 Nanoparticles Based on In-Situ Synthesis in Entropy Ligands Functionalized SiO2 Nanoreactor. Crystals. 2021; 11(10):1165. https://doi.org/10.3390/cryst11101165

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Chen, Tianju, Peng Zhang, Guoliang Chen, Qi Yang, and Feiming Li. 2021. "Improving Stability and Colloidal Dispersity of CsPbBr3@SiO2 Nanoparticles Based on In-Situ Synthesis in Entropy Ligands Functionalized SiO2 Nanoreactor" Crystals 11, no. 10: 1165. https://doi.org/10.3390/cryst11101165

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