Search Results (1,088)

This study presents the development of Cu-doped NiMo/TiO₂ photoelectrocatalysts for simultaneous green hydrogen production and pharmaceutical pollutant removal under simulated solar irradiation. The catalysts were synthesized via wet impregnation (15 wt.% total metal loading with 0.6 wt.% Cu) and thermally treated at 400 °C and 900 °C to investigate structural transformations and catalytic performance. Comprehensive characterization (XRD, BET, SEM, XPS) revealed phase transitions, enhanced crystallinity, and redistribution of redox states upon Cu incorporation, particularly the formation of NiTiO₃ and an increase in oxygen vacancies. Crystallite sizes for anatase, rutile, and brookite ranged from 21 to 47 nm at NiMoCu400, while NiMoCu900 exhibited only the rutile phase with 55 nm crystallites. BET analysis showed a surface area of 44.4 m²·g⁻¹ for NiMoCu400, and electrochemical measurements confirmed its higher electrochemically active surface area (ECSA, 2.4 cm²), indicating enhanced surface accessibility. In contrast, NiMoCu900 exhibited a much lower BET surface area (1.4 m²·g⁻¹) and ECSA (1.4 cm²), consistent with its inferior photoelectrocatalytic performance. Compared to previously reported binary NiMo/TiO₂ systems, the ternary NiMoCu/TiO₂ catalysts demonstrated significantly improved hydrogen production activity and more efficient photoelectrochemical degradation of paracetamol. Specifically, NiMoCu400 showed an anodic peak current of 0.24 mA·cm⁻² for paracetamol oxidation, representing a 60% increase over NiMo400 and a cathodic current of −0.46 mA·cm⁻² at −0.1 V vs. RHE under illumination, nearly six times higher than the undoped counterpart (–0.08 mA·cm⁻²). Mott–Schottky analysis further revealed that NiMoCu400 retained n-type behavior, while NiMoCu900 exhibited an unusual inversion to p-type, likely due to Cu migration and rutile-phase-induced realignment of donor states. Despite its higher photosensitivity, NiMoCu900 showed negligible photocurrent, confirming that structural preservation and surface redox activity are critical for photoelectrochemical performance. This work provides mechanistic insight into Cu-mediated photoelectrocatalysis and identifies NiMoCu/TiO₂ as a promising bifunctional platform for integrated solar-driven water treatment and sustainable hydrogen production. Full article

Carbon monoxide (CO) is a major toxic gas emitted from vehicle exhaust, industrial processes, and incomplete fuel combustion, posing serious environmental and health risks. Catalytic oxidation of CO into less harmful CO₂ is an effective strategy to reduce these emissions. In this study, we investigated the catalytic performance of platinum (Pt) single atoms doped on C₃N monolayers with various vacancy defects, including single carbon (C_V) and nitrogen (N_V) vacancies, using density functional theory (DFT) calculations. Our results demonstrate that Pt@N_V-C₃N exhibited the most favorable catalytic properties, with the highest O₂ adsorption energy (−3.07 eV). This performance significantly outperforms Pt atoms doped at other vacancies. It can be attributed to the strong binding between Pt and nitrogen vacancies, which contributes to its excellent resistance to Pt aggregation. CO oxidation on Pt@N_V-C₃N proceeds via the Eley–Rideal (ER2) mechanism with a low activation barrier of 0.41 eV for the rate-determining step, indicating high catalytic efficiency at low temperatures. These findings suggest that Pt@N_V-C₃N is a promising candidate for CO oxidation, contributing to developing cost-effective and environmentally sustainable catalysts. The strong binding of Pt atoms to the nitrogen vacancies prevents aggregation, ensuring the stability and durability of the catalyst. The kinetic modeling further revealed that the ER2 mechanism offers the highest reaction rate constants over a wide temperature range (273–700 K). The low activation energy barrier also facilitates CO oxidation at lower temperatures, addressing critical challenges in automotive and industrial pollution control. This study provides valuable theoretical insights for designing advanced single-atom catalysts for environmental remediation applications. Full article

The widespread adoption of sodium-ion batteries (SIBs) remains constrained by the inherent limitations of conventional anode materials, particularly their inadequate electronic conductivity, limited active sites, and pronounced structural degradation during cycling. To overcome these limitations, we propose a novel redox engineering approach to fabricate oxygen-vacancy-rich SnO₂ dots anchored on reduced graphene oxide (rGO), which are encapsulated within N-doped carbon nanofibers (denoted as ov-SnO₂/rGO@N-CNFs) through electrospinning and subsequent carbonization. The introduction of rich oxygen vacancies establishes additional sodium intercalation sites and enhances Na⁺ diffusion kinetics, while the conductive N-doped carbon network effectively facilitates charge transport and mitigates SnO₂ aggregation. Benefiting from the well-designed architecture, the hierarchical ov-SnO₂/rGO@N-CNFs electrode achieves remarkable reversible specific capacities of 351 mAh g⁻¹ after 100 cycles at 0.1 A g⁻¹ and 257.3 mAh g⁻¹ after 2000 cycles at 1.0 A g⁻¹ and maintains 177 mAh g⁻¹ even after 8000 cycles at 5.0 A g⁻¹, demonstrating exceptional long-term cycling stability and rate capability. This work offers a versatile design strategy for developing high-performance anode materials through synergistic interface engineering for SIBs. Full article

Fibrate pharmaceuticals (fibrates), as a widespread class of emerging contaminants, pose potential risks to both ecological systems and human health. The photocatalytic system based on nitrogen (N) and fluorine (F) co-doped TiO₂ nanotube arrays (NF-TNAs) provides a renewable solution for fibrate pharmaceutical removal from water, powered by inexhaustible sunlight. In this study, the degradation of two typical fibrates, i.e., bezafibrate (BZF) and ciprofibrate (CPF), under simulated sunlight irradiation through NF-TNAs were investigated. The photocatalytic degradation of BZF/CPF was achieved through combined radical and non-radical oxidation processes, while the generation and reaction mechanisms of associated reactive oxygen species (ROS) were examined. Electron paramagnetic resonance detection and quenching tests confirmed the existence of h⁺, •OH, O₂^•−, and ¹O₂, with O₂^•− playing the predominant role. The transformation products (TPs) of BZF/CPF were identified through high-resolution mass spectrometry analysis combined with quantum chemical calculations to elucidate the degradation pathways. The influence of co-existing ions and typical natural organic matters (NOM) on BZF/CPF degradation were also tested. Eventually, the ecological risk of BZF/CPF transformation products was assessed through quantitative structure–activity relationship (QSAR) modeling, and the results showed that the proposed photocatalytic system can largely alleviate fibrate toxicity. Full article

100 nm thick TiO₂/TiN bilayers with varying thickness ratios were deposited via reactive sputtering of a Ti target in controlled oxygen and nitrogen atmospheres. Post-deposition annealing in air at 600 °C was performed to induce nitrogen diffusion through the oxygen-deficient TiO₂ layer. The resulting changes in morphology and chemical environment were investigated in detail using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopy. Detailed TEM and XPS analyses have confirmed nitrogen diffusion across the TiO₂ layer, with surface nitrogen concentration and the ratio of interstitial to substitutional nitrogen dependent on the TiO₂/TiN mass ratio. Optical studies demonstrated modifications in optical constants and a reduction of the effective bandgap from 3.2 eV to 2.6 eV due to new energy states introduced by nitrogen doping. Changes in surface free energy induced by nitrogen incorporation showed a correlation to nitrogen doping sites on the surface, which had positive effects on overall photocatalytic activity. Photocatalytic activity, assessed through methylene blue degradation, showed enhancement attributed to nitrogen doping. Additionally, deposition of a 5 nm gold layer on the annealed sample enabled investigation of synergistic effects between nitrogen doping and gold incorporation, resulting in further improved photocatalytic performance. These findings establish the TiO₂/TiN bilayer as a versatile platform for supporting thin gold films with enhanced photocatalytic properties. Full article

The electrocatalytic decomposition of ammonia represents a promising route for sustainable hydrogen production, yet current systems rely heavily on noble metal catalysts with prohibitive costs and limited durability. A critical challenge lies in developing non-noble electrocatalysts that simultaneously achieve high active site exposure, optimized electronic configurations, and robust structural stability. Addressing these requirements, this study strategically engineered Cu-doped ZIF-8 architectures via in situ growth on nickel foam (NF) substrates through a facile room-temperature hydrothermal synthesis approach. Systematic optimization of the Cu/Zn molar ratio revealed that Cu_0.7Zn_0.3-ZIF/NF achieved optimal performance, exhibiting a distinctive nanoflower-like architecture that substantially increased accessible active sites. The hybrid catalyst demonstrated superior electrocatalytic performance with a current density of 124 mA cm⁻² at 1.6 V vs. RHE and a notably low Tafel slope of 30.94 mV dec⁻¹, outperforming both Zn-ZIF/NF (39.45 mV dec⁻¹) and Cu-ZIF/NF (31.39 mV dec⁻¹). Combined XPS and EDS analyses unveiled a synergistic electronic structure modulation between Zn and Cu, which facilitated charge transfer and enhanced catalytic efficiency. A gas chromatography product analysis identified H₂ and N₂ as the primary gaseous products, confirming the predominant occurrence of the ammonia oxidation reaction (AOR). This study not only presents a noble metal-free electrocatalyst with exceptional efficiency and durability for ammonia decomposition but also demonstrates the significant potential of MOF-derived materials in sustainable hydrogen production technologies. Full article

This study presents the development of a novel Cu–Co–O-codoped graphitic carbon nitride (g-C₃N₄) catalyst for efficient peroxymonosulfate (PMS) activation to degrade sulfamethoxazole (SMX) in aqueous environments. The synthesized Cu–Co–O-g-C₃N₄ catalyst demonstrated exceptional catalytic performance, achieving 90% SMX removal within 10 min—significantly outperforming pristine g-C₃N₄ (14%) and O-doped g-C₃N₄ (22%)—with a reaction rate constant of 0.63 min⁻¹. The superior activity was attributed to the synergistic effects of Cu-Co bimetallic doping and oxygen incorporation, which enhanced the active sites, stabilized metal ions, and minimized leaching. Mechanistic studies revealed a dual-pathway degradation process: (1) a radical pathway dominated by sulfate radicals (SO₄•⁻) and (2) a non-radical pathway driven by singlet oxygen (¹O₂), with the latter identified as the dominant species through quenching experiments. The catalyst exhibited broad pH adaptability and optimal performance at neutral to alkaline conditions. Characterization techniques (XRD, FTIR, XPS) confirmed successful doping and revealed that oxygen incorporation modified the electronic structure of g-C₃N₄, improving charge carrier separation. This work provides a sustainable strategy for antibiotic removal, addressing key challenges in advanced oxidation processes (AOPs), and highlights the potential of multi-heteroatom-doped carbon nitride catalysts for water purification. Full article

The efficient depolymerization of lignin has become a key challenge in the preparation of high-value-added chemicals. Graphitic carbon nitride (g-C₃N₄)-based photocatalytic system shows potential due to its mild and green characteristics over other depolymerization methods. However, its inherent defects, such as a wide band gap and rapid carrier recombination, severely limit its catalytic performance. In this paper, a g-C₃N₄ modification strategy of K⁺ doping and surface alkalinization is proposed, which is firstly applied to the photocatalytic depolymerization of the lignin β-O-4 model compound (2-phenoxy-1-phenylethanol). K⁺ doping is achieved by introducing KCl in the precursor thermal polymerization stage to weaken the edge structure strength of g-C₃N₄, and post-treatment with KOH solution is combined to optimize the surface basic groups. The structural/compositional evolution of the materials was analyzed by XRD, FTIR, and XPS. The morphology/element distribution was visualized by SEM-EDS, and the optoelectronic properties were evaluated by UV–vis DRS, PL, EIS, and transient photocurrent (TPC). K⁺ doping and surface alkalinization synergistically regulate the layered structure of the material, significantly increase the specific surface area, introduce nitrogen vacancies and hydroxyl functional groups, effectively narrow the band gap (optimized to 2.35 eV), and inhibit the recombination of photogenerated carriers by forming electron capture centers. Photocatalytic experiments show that the alkalinized g-C₃N₄ can completely depolymerize 2-phenoxy-1-phenylethanol with tunable product selectivity. By adjusting reaction time and catalyst dosage, the dominant product can be shifted from benzaldehyde (up to 77.28% selectivity) to benzoic acid, demonstrating precise control over oxidation degree. Mechanistic analysis shows that the surface alkaline sites synergistically optimize the C_β-O bond breakage path by enhancing substrate adsorption and promoting the generation of active oxygen species (·OH, ·O₂⁻). This study provides a new idea for the efficient photocatalytic depolymerization of lignin and lays an experimental foundation for the interface engineering and band regulation strategies of g-C₃N₄-based catalysts. Full article

The modification of materials is considered as one of the productive methods to facilitate the better electrochemical behavior of lithium–sulfur battery cathodes and inhibit the shuttle effect. Adopting first-principles calculations in this work, the application potential of pristine and B-, N-, and P-doped thgraphene as anchoring materials was investigated. The results reveal that pristine and doped substrates have an excellent structural stability, conductivity, and electrochemical activity. In the absence of an electric field, four substrates exhibit a strong anchoring effect on the Li₂S cluster, where the adsorption energies fall within 3.10 to 4.48 eV. Even under the external electric field, all substrates exhibit notable structural stability during Li₂S adsorption processes and maintain a high electrical conductivity, with adsorption energies exceeding 2.75 eV. Furthermore, it has been observed that the interfacial diffusion energy barriers for Li on all substrates are below 0.35 eV, which effectively enhances Li migration and facilitates reaction kinetics. Additionally, Li₂S demonstrates a low decomposition energy barrier (varying from 0.84 to 1.55 eV) on pristine and doped substrates, enabling the efficient regeneration of the active material during the battery cycling. These findings offer a scientific guideline for the design of pristine and doped thgraphene as an excellent anchoring material for advanced lithium–sulfur batteries. Full article

(1) Background: The highly pathogenic avian influenza virus H5N1 clade 2.3.4.4b is an emerging threat that poses a great risk to the poultry industry. A few human cases have been linked to the infection with this clade in many parts of the world, including the USA. Unfortunately, there are no specific vaccines or antiviral drugs that could help prevent and treat the infection caused by this virus in birds. Our major objective is to identify/repurpose some (novel/known) antiviral compounds that may inhibit viral replication by targeting some key viral proteins. (2) Methods: We used state-of-the-art machine learning tools such as molecular docking and MD-simulation methods from Biovia Discovery Studio (v24.1.0.321712). The key target proteins such as hemagglutinin (HA), neuraminidase (NA), Matrix-2 protein (M2), and the cap-binding domain of PB2 (PB2/CBD) homology models were validated through structural assessment via DOPE scores, Ramachandran plots, and Verify-3D metrics, ensuring reliable structural representations, confirming their reliability for subsequent in silico approaches. These approaches include molecular docking followed by molecular dynamics simulation for 50 nanoseconds (ns), highlighting the structural stability and compactness of the docked complexes. (3) Results: Molecular docking revealed strong binding affinities for both sofosbuvir and GS441524, particularly with the NA and PB2/CBD protein targets. Among them, GS441524 exhibited superior interaction scores and a greater number of hydrogen bonds with key functional residues of NA and PB2/CBD. The MM-GBSA binding free energy calculations further supported these findings, as GS441524 displayed more favorable binding energies compared to several known standard inhibitors, including F0045S for HA, Zanamivir for NA, Rimantadine and Amantadine for M2, and PB2-39 for PB2/CBD. Additionally, 50 ns molecular dynamics simulations highlighted the structural stability and compactness of the GS441524-PB2/CBD complex, further supporting its potential as a promising antiviral candidate. Furthermore, hydrogen bond monitor analysis over the 50 ns simulation confirmed persistent and specific interactions between the ligand and proteins, suggesting that GS441524 may effectively inhibit the NA, and PB2/CBD might potentially disrupt PB2-mediated RNA synthesis. (4) Conclusions: Our findings are consistent with previous evidence supporting the antiviral activity of certain nucleoside analog inhibitors, including GS441524, against various coronaviruses. These results further support the potential repurposing of GS441524 as a promising therapeutic candidate against H5N1 avian influenza clade 2.3.4.4b. However, further functional studies are required to validate these in silico predictions and support the inhibitory action of GS441524 against the targeted proteins of H5N1, specifically clade 2.3.4.4b. Full article

The increasing demand for efficient and sustainable energy conversion technologies has driven extensive research into alternative electrocatalysts for the oxygen reduction reaction (ORR). Platinum-based catalysts, while highly efficient, suffer from high costs, scarcity, and long-term instability Laser-Induced Graphene (LIG) has recently attracted considerable interest as an effective metal-free electrocatalyst for oxygen reduction reaction (ORR), owing to its remarkable electrical conductivity, customizable surface functionalities, and multi-scale porous architecture. This review explores the synthesis strategies, physicochemical properties, and ORR catalytic performance of LIG. Additionally, this review offered a detailed overview regarding the effective pole of heteroatom doping (N, S, P, B) and functionalization techniques to enhance catalytic activity. Finally, we highlight the current challenges and future perspectives of LIG-based ORR catalysts for fuel cells and other electrochemical energy applications. Furthermore, laser-induced-graphene (LIG) has emerged as a highly attractive candidate for electrochemical energy conversion systems, due to its large specific surface area, tunable porosity, excellent electrical conductivity, and cost-effective fabrication process. This review discusses recent advancements in LIG synthesis, its structural and electrochemical properties, and its applications in supercapacitors, batteries, fuel cells, and electrocatalysis. Despite its advantages, challenges such as mechanical stability, electrochemical degradation, and large-scale production remain key areas for improvement. Additionally, this review explores future perspectives on optimizing LIG for next-generation energy storage and conversion technologies. Full article

Rapid economic growth has led to an increase in the use of multilayer plastic packaging, which involves complex polymer compositions and hinders recycling. This study investigated the catalytic pyrolysis of plastic packaging waste in a 3000 cm³ semibatch reactor, aiming to optimize kerosene-like hydrocarbon production. The temperature (420–500 °C), N₂ flow rate (25–125 mL/min), and catalyst loading (5–20 wt.%) were examined individually and in combination with activated carbon and an Fe-doped dolomite (Fe/DM) catalyst. Central composite design (CCD) and response surface methodology (RSM) were used to identify the optimal conditions and synergistic effects. Pyrolysis product analysis involved simulation distillation gas chromatography (Sim-DGC), gas chromatography/mass spectrometry (GC/MS), and Fourier transform infrared (FT-IR) spectroscopy. The optimal conditions (440 °C, 50 mL/min N₂ flow, catalyst loading of 10 wt.% using a 5 wt.% Fe-doped dolomite-activated carbon 0.6:0.4 mass/molar ratio) yielded the highest pyrolysis oil (79.6 ± 0.35 wt.%) and kerosene-like fraction (22.3 ± 0.22 wt.%). The positive synergistic effect of Fe/DM and activated carbon (0.6:0.4) enhanced the catalytic activity, promoting long-chain polymer degradation into mid-range hydrocarbons, with secondary cracking yielding smaller hydrocarbons. The pore structure and acid sites of the catalyst improved the conversion of intermediate hydrocarbons into aliphatic compounds (C₅–C₁₅), increasing kerosene-like hydrocarbon production. Full article

5-Hydroxymethylfurfural (HMF) is a versatile platform molecule with the potential to replace many fossil fuel derivatives. It can be obtained through the dehydration of carbohydrates. In this study, we present a simple and cost-effective microwave-assisted method for producing HMF. This method involves the use of readily available sucrose as a substrate and glucose-derived bifunctional hydrochars as carbocatalysts. These catalysts were produced via hydrothermal carbonisation using thiourea and urea as nitrogen and sulphur sources, respectively, to introduce Brønsted acidic and basic sites into the materials. Using a microwave reactor, we found that the S, N-doped hydrochars were active in sucrose dehydration in water. Catalytic results showed that HMF yield depended on the balance between acidic and basic sites as well as the types of S and N species present on the surfaces of these hydrochars. The best-performing catalyst achieved an encouraging HMF yield of 37%. The potential of N, S-co-doped biochar as a green solid catalyst for various biorefinery processes was demonstrated. A simple kinetic model was developed to elucidate the kinetics of the main reaction pathways of this cascade process, showing a very good fit with the experimental results. The calculated rate constants revealed that reactions with a 5% sucrose loading exhibited significantly higher fructose dehydration rates and produced fewer side products than reactions using a more diluted substrate. No isomerisation of glucose into fructose was observed in an air atmosphere. On the contrary, a limited rate of isomerisation of glucose into fructose was recorded in an oxygen atmosphere. Therefore, efforts should focus on achieving a high glucose-to-fructose isomerisation rate (an intermediate reaction step) to improve HMF selectivity by reducing humin formation. Full article

The simultaneous generation of hydrogen fuel and wastewater remediation via electrocatalytic urea oxidation has emerged as a promising approach for sustainable energy and environmental solutions. However, the practical application of this process is hindered by the limited active sites and high charge-transfer resistance of conventional anode materials. In this work, we introduce a novel CoP@P, N-CNTs/NF electrocatalyst, fabricated through a facile one-step thermal annealing technique. Comprehensive characterizations confirm the successful integration of CoP nanoparticles and phosphorus/nitrogen co-doped carbon nanotubes (P, N-CNTs) onto nickel foam, yielding a unique hierarchical structure that offers abundant active sites and accelerated electron transport. As a result, the CoP@P, N-CNTs/NF electrode achieves outstanding urea oxidation reaction (UOR) performance, delivering current densities of 158.5 mA cm⁻² at 1.5 V and 232.95 mA cm⁻² at 1.6 V versus RHE, along with exceptional operational stability exceeding 50 h with negligible performance loss. This innovative, multi-element-doped electrode design marks a significant advancement in the field, enabling highly efficient UOR and energy-efficient hydrogen production. Our approach paves the way for scalable, cost-effective solutions that couple renewable energy generation with effective wastewater treatment. Full article

Graphite carbon nitride (g-C₃N₄) is a low band gap non-metallic polymer semiconductor that has broad application prospects and is an ideal material for absorbing visible light, as g-C₃N₄ materials have strong oxidation properties and are easy to modify. The structure formation of g-C₃N₄-based materials makes a series of photocatalytic synthesis reactions possible and improves photocatalytic reaction activity. In this paper, the development history, structures, and performance of g-C₃N₄ are briefly introduced, and the modification strategies of g-C₃N₄ are summarized to improve its photocatalytic and photoelectric catalytic properties via doping, heterojunction construction, etc. The light absorption and utilization of the catalysts are also analyzed in terms of light source conditions, and the application of g-C₃N₄ and its modified materials in photocatalysis and photocatalytic degradation is reviewed. Full article