Login In
2025 Volume 41 Issue 6
2025, 41(6):
Abstract:
2025, 41(6): 100063
doi: 10.1016/j.actphy.2025.100063
Abstract:
With the profound transformation of the global energy landscape and the rapid advancement of portable electronic devices and electric vehicle industries, there is an increasingly urgent demand for high-performance energy storage devices. Among the available energy storage technologies, supercapacitors stand out due to their rapid charge/discharge capabilities, excellent cycling stability, and high power density, enabling reliable long-term operation as well as efficient energy conversion and storage. A fundamental challenge in contemporary energy storage research remains the enhancement of supercapacitor energy density while maintaining their inherent high power density capabilities. Two-dimensional (2D) materials have emerged as promising candidates for constructing high-performance supercapacitor electrodes. Materials such as graphene, transition metal nitrides and/or carbides (MXenes), and transition metal dichalcogenides possess unique layered structures with atomic thickness, exceptional surface areas, high theoretical capacities, and remarkable mechanical flexibility. These characteristics make them particularly suitable for developing next-generation energy storage devices. However, the inherent van der Waals interactions between nanosheets frequently result in restacking phenomena, significantly impeding ion transport and consequently limiting both practical capacity and rate performance. Thus, rational materials design and precise electrode architecture engineering are imperative for overcoming these performance limitations. This review first explores modification strategies for enhancing the electrochemical performance of 2D materials. Studies have shown that diverse modification approaches, including surface functionalization, defect engineering, and heterogeneous structure construction, can effectively increase active sites, enhance conductivity, and improve pseudocapacitive characteristics. These modifications lead to substantial improvements in both areal and volumetric capacitance of electrode materials. Notably, efforts to increase supercapacitor energy density typically necessitate higher active material mass loading, which inherently results in more complex and extended ion transport pathways within the electrode structure, thereby compromising rate performance. In addressing this challenge, we evaluate conventional methodologies for establishing ion transport channels in high mass loading electrodes, including template-based approaches, external field-induced assembly techniques, and three-dimensional (3D) printing processes. However, these traditional methods typically generate pore structures at the micrometer or sub-micrometer scale, making it challenging to simultaneously achieve optimal rate performance and volumetric capacitance. To concurrently optimize areal capacitance, volumetric capacitance, and rate performance, this review emphasizes recent innovative approaches for constructing nanoscale porous architectures. These include capillary force-driven densification, interlayer insertion strategies, surface etching techniques, and quantum dot methodologies. These advanced approaches aim to establish three-dimensional interconnected networks for efficient ion transport, thereby accelerating the development of miniaturized supercapacitor technologies that simultaneously achieve high energy density and high power density characteristics.
With the profound transformation of the global energy landscape and the rapid advancement of portable electronic devices and electric vehicle industries, there is an increasingly urgent demand for high-performance energy storage devices. Among the available energy storage technologies, supercapacitors stand out due to their rapid charge/discharge capabilities, excellent cycling stability, and high power density, enabling reliable long-term operation as well as efficient energy conversion and storage. A fundamental challenge in contemporary energy storage research remains the enhancement of supercapacitor energy density while maintaining their inherent high power density capabilities. Two-dimensional (2D) materials have emerged as promising candidates for constructing high-performance supercapacitor electrodes. Materials such as graphene, transition metal nitrides and/or carbides (MXenes), and transition metal dichalcogenides possess unique layered structures with atomic thickness, exceptional surface areas, high theoretical capacities, and remarkable mechanical flexibility. These characteristics make them particularly suitable for developing next-generation energy storage devices. However, the inherent van der Waals interactions between nanosheets frequently result in restacking phenomena, significantly impeding ion transport and consequently limiting both practical capacity and rate performance. Thus, rational materials design and precise electrode architecture engineering are imperative for overcoming these performance limitations. This review first explores modification strategies for enhancing the electrochemical performance of 2D materials. Studies have shown that diverse modification approaches, including surface functionalization, defect engineering, and heterogeneous structure construction, can effectively increase active sites, enhance conductivity, and improve pseudocapacitive characteristics. These modifications lead to substantial improvements in both areal and volumetric capacitance of electrode materials. Notably, efforts to increase supercapacitor energy density typically necessitate higher active material mass loading, which inherently results in more complex and extended ion transport pathways within the electrode structure, thereby compromising rate performance. In addressing this challenge, we evaluate conventional methodologies for establishing ion transport channels in high mass loading electrodes, including template-based approaches, external field-induced assembly techniques, and three-dimensional (3D) printing processes. However, these traditional methods typically generate pore structures at the micrometer or sub-micrometer scale, making it challenging to simultaneously achieve optimal rate performance and volumetric capacitance. To concurrently optimize areal capacitance, volumetric capacitance, and rate performance, this review emphasizes recent innovative approaches for constructing nanoscale porous architectures. These include capillary force-driven densification, interlayer insertion strategies, surface etching techniques, and quantum dot methodologies. These advanced approaches aim to establish three-dimensional interconnected networks for efficient ion transport, thereby accelerating the development of miniaturized supercapacitor technologies that simultaneously achieve high energy density and high power density characteristics.
2025, 41(6): 100051
doi: 10.1016/j.actphy.2025.100051
Abstract:
The sluggish electron migration rate and pronounced electron-hole recombination, pose significant obstacles to achieving high photocatalytic efficiency. The utilization of multiple catalysts for the construction of heterojunctions can effectively enhance charge separation. A series of Keggin-type hollow dodecahedral polyoxometalates were prepared via hydrothermal synthesis, and their molecular orbitals were modified through the addition of metal elements. The incorporation of metal elements modulated the electronic structure of polyoxometalates, effectively enhancing the electron aggregation capability of polyoxometalates. Single-component catalysts often face serious hole-electron recombination. In order to solve this problem, the scheme of constructing heterojunction is proposed to improve the electron transport efficiency. By immobilizing ZnCdS nanoparticles onto the polyoxometalate surface, the heterojunction architecture was engineered to significantly enhance the interfacial charge transfer capability. Density Functional Theory (DFT) calculations and the experimental results indicate that the modulation of metallic components renders the polyoxometalate a more favorable energy-level orbital. The catalytic mechanism of ZnCdS and KMoP S-scheme heterojunction was also verified. The formation of S-scheme heterojunctions further improves the electron transfer efficiency compared to other traditional heterojunctions, achieving efficient utilization of photo generated electrons and holes. Additionally, the S-scheme heterojunction shifts the catalyst's d-band center closer to the Fermi level, thereby improving electrical conductivity. This article provides a new approach for energy level regulation of polyoxometalates and the design of S-scheme heterojunctions.
The sluggish electron migration rate and pronounced electron-hole recombination, pose significant obstacles to achieving high photocatalytic efficiency. The utilization of multiple catalysts for the construction of heterojunctions can effectively enhance charge separation. A series of Keggin-type hollow dodecahedral polyoxometalates were prepared via hydrothermal synthesis, and their molecular orbitals were modified through the addition of metal elements. The incorporation of metal elements modulated the electronic structure of polyoxometalates, effectively enhancing the electron aggregation capability of polyoxometalates. Single-component catalysts often face serious hole-electron recombination. In order to solve this problem, the scheme of constructing heterojunction is proposed to improve the electron transport efficiency. By immobilizing ZnCdS nanoparticles onto the polyoxometalate surface, the heterojunction architecture was engineered to significantly enhance the interfacial charge transfer capability. Density Functional Theory (DFT) calculations and the experimental results indicate that the modulation of metallic components renders the polyoxometalate a more favorable energy-level orbital. The catalytic mechanism of ZnCdS and KMoP S-scheme heterojunction was also verified. The formation of S-scheme heterojunctions further improves the electron transfer efficiency compared to other traditional heterojunctions, achieving efficient utilization of photo generated electrons and holes. Additionally, the S-scheme heterojunction shifts the catalyst's d-band center closer to the Fermi level, thereby improving electrical conductivity. This article provides a new approach for energy level regulation of polyoxometalates and the design of S-scheme heterojunctions.
2025, 41(6): 100052
doi: 10.1016/j.actphy.2025.100052
Abstract:
Photocatalytic microplastic (MP) degradation via reactive oxygen species (ROS) is a considered environmentally friendly and sustainable approach for eliminating MP pollution in aquatic environments. However, it faces challenges due to the low migration and rapid recombination efficiency of charge carriers in photocatalysts. Herein, oxygen and sulfur co-doped carbon nitride (OSCN) nanosheets were synthesized through thermal polymerization coupled with a thermosolvent process. The O and S co-doping can reduce the bandgap and improve the light response of carbon nitride (C3N4). Meanwhile, O/S dopants effectively improve the delocalization of electron distribution, leading to increased carrier separation capacity, thereby promoting the formation of ROS and enhancing photocatalytic performance. Compared to C3N4, OSCN demonstrated significantly higher photocatalytic degradation and mineralization rates for MPs, including polyethylene (PE, traditional petroleum-based MPs) and polylactic acid (PLA, biodegradable bio-based MPs). Specifically, the mass loss of PE and PLA increased by 32.8% and 34.1%, respectively. Notably, ·OH and 1O2 generated by OSCN synergistically catalyzed the degradation of PE, while ·OH was the primary radical triggering the photolysis and hydrolysis of PLA. This study holds significant implications for the application of photocatalysis technology in the remediation of MP pollution in aquatic environments.
Photocatalytic microplastic (MP) degradation via reactive oxygen species (ROS) is a considered environmentally friendly and sustainable approach for eliminating MP pollution in aquatic environments. However, it faces challenges due to the low migration and rapid recombination efficiency of charge carriers in photocatalysts. Herein, oxygen and sulfur co-doped carbon nitride (OSCN) nanosheets were synthesized through thermal polymerization coupled with a thermosolvent process. The O and S co-doping can reduce the bandgap and improve the light response of carbon nitride (C3N4). Meanwhile, O/S dopants effectively improve the delocalization of electron distribution, leading to increased carrier separation capacity, thereby promoting the formation of ROS and enhancing photocatalytic performance. Compared to C3N4, OSCN demonstrated significantly higher photocatalytic degradation and mineralization rates for MPs, including polyethylene (PE, traditional petroleum-based MPs) and polylactic acid (PLA, biodegradable bio-based MPs). Specifically, the mass loss of PE and PLA increased by 32.8% and 34.1%, respectively. Notably, ·OH and 1O2 generated by OSCN synergistically catalyzed the degradation of PE, while ·OH was the primary radical triggering the photolysis and hydrolysis of PLA. This study holds significant implications for the application of photocatalysis technology in the remediation of MP pollution in aquatic environments.
2025, 41(6): 100053
doi: 10.1016/j.actphy.2025.100053
Abstract:
Metallic 1T Molybdenum disulfide (1T-MoS2) exhibits enhanced full spectral light absorption and prominent electrical conductivity, making it ideal for photothermal applications in conjunction with Ti3C2Tx MXene. Despite the challenges in increasing the 1T-MoS2 proportion within MoS2/Ti3C2Tx heterostructures and the incomplete understanding of the mechanisms governing their formation and properties, herein, a combined theoretical and experimental framework has been established, suggesting that the metallic characteristics of Ti3C2Tx and 1T-MoS2 could significantly improve photothermal performance through strong interlayer interactions and efficient electron transport. The hierarchical MoS2/Ti3C2Tx heterostructure has been fabricated through a one-step hydrothermal synthesis method with enhanced 1T-MoS2 proportion, which achieves multilayered wrinkled architecture resulting from the in-situ growth of MoS2 on Ti3C2Tx nanosheets. Notably, a remarkable peak photoheating temperature of 107 °C under an 808 nm laser with an intensity of 0.5 W·cm-2 is realized, demonstrating its exceptional photothermal conversion capability. By incorporated into a polyvinylidene difluoride membrane, the MoS2/Ti3C2Tx heterostructure functions as an efficient self-floating solar-driven steam generator, reaching an evaporation rate of 1.79 kg·m-2·h-1 and an evaporation efficiency of 96.4% under one solar irradiance. This study proposes a versatile strategy for the MoS2/Ti3C2Tx heterostructure, offering the potential for sustainable solar-driven vapor generation technologies.
Metallic 1T Molybdenum disulfide (1T-MoS2) exhibits enhanced full spectral light absorption and prominent electrical conductivity, making it ideal for photothermal applications in conjunction with Ti3C2Tx MXene. Despite the challenges in increasing the 1T-MoS2 proportion within MoS2/Ti3C2Tx heterostructures and the incomplete understanding of the mechanisms governing their formation and properties, herein, a combined theoretical and experimental framework has been established, suggesting that the metallic characteristics of Ti3C2Tx and 1T-MoS2 could significantly improve photothermal performance through strong interlayer interactions and efficient electron transport. The hierarchical MoS2/Ti3C2Tx heterostructure has been fabricated through a one-step hydrothermal synthesis method with enhanced 1T-MoS2 proportion, which achieves multilayered wrinkled architecture resulting from the in-situ growth of MoS2 on Ti3C2Tx nanosheets. Notably, a remarkable peak photoheating temperature of 107 °C under an 808 nm laser with an intensity of 0.5 W·cm-2 is realized, demonstrating its exceptional photothermal conversion capability. By incorporated into a polyvinylidene difluoride membrane, the MoS2/Ti3C2Tx heterostructure functions as an efficient self-floating solar-driven steam generator, reaching an evaporation rate of 1.79 kg·m-2·h-1 and an evaporation efficiency of 96.4% under one solar irradiance. This study proposes a versatile strategy for the MoS2/Ti3C2Tx heterostructure, offering the potential for sustainable solar-driven vapor generation technologies.
2025, 41(6): 100054
doi: 10.1016/j.actphy.2025.100054
Abstract:
Plasma-activated heterogeneous catalysis is a promising strategy for catalytic CO2 hydrogenation under mild conditions. In this study, pore structures with deep pore channels were constructed on Al2O3-x via a soft template method, and Cu/Al2O3-x was prepared by an impregnation method, with Al2O3-x serving as the support for plasma-catalyzed CO2 hydrogenation to dimethyl ether (DME). Cu/Al2O3-0.75/HZSM-5 demonstrated a high performance and discharge efficiency for plasma-catalyzed CO2 hydrogenation. The CO2 conversion and DME yield for plasma-catalyzed CO2 hydrogenation on Cu/Al2O3-0.75/HZSM-5 reached 21.98% and 9.83%, respectively, with selectivities for CO, CH3OH, and DME on Cu/Al2O3-0.75/HZSM-5 of 25.39%, 29.89%, and 44.72%, respectively. The deep pore structures on Al2O3-x serve as Cu loading sites, and the confinement effect of the pores enhances the metal-support interaction and Cu metal dispersion. More abundant and stronger Brønsted basic and Lewis acidic sites facilitate the activation and hydrogenation of CO2. Notably, the electric field formed by Cu sites anchored in the deep pore channel structures is conducive to guiding the activated plasma CO2 intermediates into the difficult-to-access pores for hydrogenation. Hydrogenation of the plasma-activated CO2 intermediates in the deep pore channels is crucial for improving plasma-catalyzed CO2 hydrogenation to DME.
Plasma-activated heterogeneous catalysis is a promising strategy for catalytic CO2 hydrogenation under mild conditions. In this study, pore structures with deep pore channels were constructed on Al2O3-x via a soft template method, and Cu/Al2O3-x was prepared by an impregnation method, with Al2O3-x serving as the support for plasma-catalyzed CO2 hydrogenation to dimethyl ether (DME). Cu/Al2O3-0.75/HZSM-5 demonstrated a high performance and discharge efficiency for plasma-catalyzed CO2 hydrogenation. The CO2 conversion and DME yield for plasma-catalyzed CO2 hydrogenation on Cu/Al2O3-0.75/HZSM-5 reached 21.98% and 9.83%, respectively, with selectivities for CO, CH3OH, and DME on Cu/Al2O3-0.75/HZSM-5 of 25.39%, 29.89%, and 44.72%, respectively. The deep pore structures on Al2O3-x serve as Cu loading sites, and the confinement effect of the pores enhances the metal-support interaction and Cu metal dispersion. More abundant and stronger Brønsted basic and Lewis acidic sites facilitate the activation and hydrogenation of CO2. Notably, the electric field formed by Cu sites anchored in the deep pore channel structures is conducive to guiding the activated plasma CO2 intermediates into the difficult-to-access pores for hydrogenation. Hydrogenation of the plasma-activated CO2 intermediates in the deep pore channels is crucial for improving plasma-catalyzed CO2 hydrogenation to DME.
2025, 41(6): 100055
doi: 10.1016/j.actphy.2025.100055
Abstract:
Photocatalytic carbon dioxide (CO2) reduction represents a hopeful approach to addressing global energy and environmental issues. The quest for catalysts that demonstrate both high activity and selectivity for CO2 conversion has attracted significant attention. In this study, ultrathin N-doped BiOBr was synthesized using a simple straightforward method. Systematic experimental results indicated that N-doping reduced the thickness of the BiOBr nanosheets and increased their specific surface area. Moreover, the efficiency of photogenerated charge carrier migration and the CO2 adsorption capacity were significantly enhanced, contributing to improved CO2 photoreduction performance. Experimental results showed that the 2N-BiOBr exhibited the best catalytic performance, with a CO evolution rate of 18.28 μmol·g-1·h-1 and nearly 100% CO selectivity in water, which was three times higher than that of pure BiOBr. The potential photocatalytic mechanism was investigated using in situ FTIR analysis and DFT simulations. Mechanistic studies revealed that N atoms replaced O atoms as adsorption centers, enhancing the strong adsorption selectivity towards CO2 over O―H in BiOBr and facilitating the formation of key reaction intermediates. This study provides new perspectives on the creation and development of effective photocatalytic materials, offering theoretical support for the application of photocatalytic technology in energy and environmental science.
Photocatalytic carbon dioxide (CO2) reduction represents a hopeful approach to addressing global energy and environmental issues. The quest for catalysts that demonstrate both high activity and selectivity for CO2 conversion has attracted significant attention. In this study, ultrathin N-doped BiOBr was synthesized using a simple straightforward method. Systematic experimental results indicated that N-doping reduced the thickness of the BiOBr nanosheets and increased their specific surface area. Moreover, the efficiency of photogenerated charge carrier migration and the CO2 adsorption capacity were significantly enhanced, contributing to improved CO2 photoreduction performance. Experimental results showed that the 2N-BiOBr exhibited the best catalytic performance, with a CO evolution rate of 18.28 μmol·g-1·h-1 and nearly 100% CO selectivity in water, which was three times higher than that of pure BiOBr. The potential photocatalytic mechanism was investigated using in situ FTIR analysis and DFT simulations. Mechanistic studies revealed that N atoms replaced O atoms as adsorption centers, enhancing the strong adsorption selectivity towards CO2 over O―H in BiOBr and facilitating the formation of key reaction intermediates. This study provides new perspectives on the creation and development of effective photocatalytic materials, offering theoretical support for the application of photocatalytic technology in energy and environmental science.
2025, 41(6): 100064
doi: 10.1016/j.actphy.2025.100064
Abstract:
Photocatalytic hydrogen peroxide (H2O2) production is a crucial process for clean energy conversion, involving the reduction of O2 through two electrons. However, this process is often hampered by the sluggish water oxidation involving the photogenerated holes. To address this challenge, we have constructed a dual-functional S-scheme ZnO/CdIn2S4 heterojunction systerm coupling the H2O2 generation with a value-added benzylamine (BA) oxidation reaction. In this dual-functional photocatalytic system, photogenerated electrons in CdIn2S4 efficiently reduce O2 to produce H2O2, while photogenerated holes in ZnO selectively oxidize BA to N-benzylidenebenzylamine. Leveraging the advantages of the S-scheme heterojunction, the optimized ZnO/CdIn2S4 photocatalyst displays an enhanced H2O2 production rate (386 μmol·L-1·h-1) and BA oxidation fraction (81%) than pure ZnO or CdIn2S4. Femtosecond transient absorption (fs-TA) spectroscopy confirm the ultrafast S-scheme electron transfer from the ZnO conduction band (CB) to the CdIn2S4 valence band (VB) upon photoexcitation of the ZnO/CdIn2S4 composite. Besides, timely depletion of VB holes in ZnO and CB electrons in CdIn2S4 can accelerate the interfacial electron transfer in the ZnO/CdIn2S4 S-scheme heterojunction. The innovative design of the ZnO/CdIn2S4 S-scheme photocatalyst provides new insights for developing efficient dual-functional heterojunction photocatalytic systems and introduces a novel method for studying S-scheme heterojunctions using fs-TA spectroscopy.
Photocatalytic hydrogen peroxide (H2O2) production is a crucial process for clean energy conversion, involving the reduction of O2 through two electrons. However, this process is often hampered by the sluggish water oxidation involving the photogenerated holes. To address this challenge, we have constructed a dual-functional S-scheme ZnO/CdIn2S4 heterojunction systerm coupling the H2O2 generation with a value-added benzylamine (BA) oxidation reaction. In this dual-functional photocatalytic system, photogenerated electrons in CdIn2S4 efficiently reduce O2 to produce H2O2, while photogenerated holes in ZnO selectively oxidize BA to N-benzylidenebenzylamine. Leveraging the advantages of the S-scheme heterojunction, the optimized ZnO/CdIn2S4 photocatalyst displays an enhanced H2O2 production rate (386 μmol·L-1·h-1) and BA oxidation fraction (81%) than pure ZnO or CdIn2S4. Femtosecond transient absorption (fs-TA) spectroscopy confirm the ultrafast S-scheme electron transfer from the ZnO conduction band (CB) to the CdIn2S4 valence band (VB) upon photoexcitation of the ZnO/CdIn2S4 composite. Besides, timely depletion of VB holes in ZnO and CB electrons in CdIn2S4 can accelerate the interfacial electron transfer in the ZnO/CdIn2S4 S-scheme heterojunction. The innovative design of the ZnO/CdIn2S4 S-scheme photocatalyst provides new insights for developing efficient dual-functional heterojunction photocatalytic systems and introduces a novel method for studying S-scheme heterojunctions using fs-TA spectroscopy.
2025, 41(6): 100065
doi: 10.1016/j.actphy.2025.100065
Abstract:
Improving the separation efficiency of photogenerated charge carriers to significantly enhance the redox capability of photocatalysts remains a major challenge in the field of photocatalysis. To address this issue, this study successfully synthesized a CeO2/Bi19Br3S27 S-scheme heterojunction catalyst using a hydrothermal method, aiming to enhance the photocatalytic performance of the catalyst. The synthesis of the CeO2/Bi19Br3S27 composite not only improved the separation efficiency of photogenerated charge carriers but also endowed the catalyst with stronger redox capabilities and greater driving force, significantly boosting its photocatalytic performance. Experimental results showed that the CO production rate of the CeO2/Bi19Br3S27 composite catalyst reached 13.5 μmol g-1 h-1, which is 5.19 times higher than that of the pure Bi19Br3S27 catalyst and 2.81 times higher than that of the pure CeO2 catalyst. This significant enhancement indicates that the CeO2/Bi19Br3S27 composite catalyst exhibited stronger catalytic performance in CO generation reactions. Furthermore, CeO2/Bi19Br3S27 catalyst achieved a CH4 production rate of 4.3 μmol g-1 h-1, which is 3.1 times higher than that of the CeO2 catalyst and 2.7 times higher than that of the Bi19Br3S27 catalyst, further confirming its superior performance in CH4 generation reactions. These results demonstrate that the CeO2/Bi19Br3S27 composite catalyst not only shows significant improvements in CO and CH4 production rates but also exhibits excellent photocatalytic performance, highlighting its potential application in the field of photocatalysis. This study provides new insights into improving the separation efficiency of photogenerated charges and offers valuable references for the future development of highly efficient photocatalytic materials. By constructing the S-scheme heterojunction structure, the recombination of photogenerated charge carriers can be effectively suppressed, thereby enhancing the efficiency of photocatalytic reactions and providing a new solution for sustainable energy utilization.
Improving the separation efficiency of photogenerated charge carriers to significantly enhance the redox capability of photocatalysts remains a major challenge in the field of photocatalysis. To address this issue, this study successfully synthesized a CeO2/Bi19Br3S27 S-scheme heterojunction catalyst using a hydrothermal method, aiming to enhance the photocatalytic performance of the catalyst. The synthesis of the CeO2/Bi19Br3S27 composite not only improved the separation efficiency of photogenerated charge carriers but also endowed the catalyst with stronger redox capabilities and greater driving force, significantly boosting its photocatalytic performance. Experimental results showed that the CO production rate of the CeO2/Bi19Br3S27 composite catalyst reached 13.5 μmol g-1 h-1, which is 5.19 times higher than that of the pure Bi19Br3S27 catalyst and 2.81 times higher than that of the pure CeO2 catalyst. This significant enhancement indicates that the CeO2/Bi19Br3S27 composite catalyst exhibited stronger catalytic performance in CO generation reactions. Furthermore, CeO2/Bi19Br3S27 catalyst achieved a CH4 production rate of 4.3 μmol g-1 h-1, which is 3.1 times higher than that of the CeO2 catalyst and 2.7 times higher than that of the Bi19Br3S27 catalyst, further confirming its superior performance in CH4 generation reactions. These results demonstrate that the CeO2/Bi19Br3S27 composite catalyst not only shows significant improvements in CO and CH4 production rates but also exhibits excellent photocatalytic performance, highlighting its potential application in the field of photocatalysis. This study provides new insights into improving the separation efficiency of photogenerated charges and offers valuable references for the future development of highly efficient photocatalytic materials. By constructing the S-scheme heterojunction structure, the recombination of photogenerated charge carriers can be effectively suppressed, thereby enhancing the efficiency of photocatalytic reactions and providing a new solution for sustainable energy utilization.
2025, 41(6): 100067
doi: 10.1016/j.actphy.2025.100067
Abstract:
The intrinsic surface atomic configuration of photocatalyst without unstable or difficult-to-generate atomic vacancies often limits the formation of effective interaction between metal single atom (MSA) cocatalyst and photocatalyst, thus inhibiting the stability and performance improvement of single-atom photocatalysts. In this study, we present a convenient and cost-effective photochemical oxygen reduction reaction (ORR) mechanism to prepare thermodynamically stable noble metal single-atom cocatalysts on TiO2 photocatalyst under mild condition (only consuming water and oxygen at 101325 Pa and 25 °C). The first-principles simulation firstly theoretically reveals that the intrinsic surface configuration of TiO2 can only produce unstable Pt―O2 structure. However, ORR occurring on TiO2 can not only provide one foreign oxygen to coordinate with Pt single atom (PtSA), but also induce one surface lattice oxygen to move toward PtSA, promoting the formation of one thermodynamically stable Pt―O4 species, demonstrated by the experimental synthesis of PtSA on TiO2 in oxygen atmosphere instead of inert atmosphere. The obtained stable PtSA-TiO2 photocatalysts exhibit a photocatalytic rate of 320.4 mmol·g-1·h-1 for the coproduction of high-purity hydrogen and value-added acetaldehyde with a selectivity of 99.65%, three-fold higher than the activity of Pt nanoparticles-loaded TiO2. This strategy is further extended to other noble metals, such as Rh and Pd.
The intrinsic surface atomic configuration of photocatalyst without unstable or difficult-to-generate atomic vacancies often limits the formation of effective interaction between metal single atom (MSA) cocatalyst and photocatalyst, thus inhibiting the stability and performance improvement of single-atom photocatalysts. In this study, we present a convenient and cost-effective photochemical oxygen reduction reaction (ORR) mechanism to prepare thermodynamically stable noble metal single-atom cocatalysts on TiO2 photocatalyst under mild condition (only consuming water and oxygen at 101325 Pa and 25 °C). The first-principles simulation firstly theoretically reveals that the intrinsic surface configuration of TiO2 can only produce unstable Pt―O2 structure. However, ORR occurring on TiO2 can not only provide one foreign oxygen to coordinate with Pt single atom (PtSA), but also induce one surface lattice oxygen to move toward PtSA, promoting the formation of one thermodynamically stable Pt―O4 species, demonstrated by the experimental synthesis of PtSA on TiO2 in oxygen atmosphere instead of inert atmosphere. The obtained stable PtSA-TiO2 photocatalysts exhibit a photocatalytic rate of 320.4 mmol·g-1·h-1 for the coproduction of high-purity hydrogen and value-added acetaldehyde with a selectivity of 99.65%, three-fold higher than the activity of Pt nanoparticles-loaded TiO2. This strategy is further extended to other noble metals, such as Rh and Pd.
2025, 41(6): 100068
doi: 10.1016/j.actphy.2025.100068
Abstract:
The simultaneous enhancement of separation and utilization of bulk and surface charges is crucial for achieving efficient photocatalytic H2 evolution reactions. In this study, NiCr2O4/T-CZS composites were fabricated by incorporating NiCr2O4 nanosheets onto the surface of twinned Cd0.5Zn0.5S (T-CZS) nanoparticles using a solvent evaporation strategy. After optimization, the 6% NiCr2O4/T-CZS exhibited an impressive hydrogen (H2) evolution rate (rH2) of 81.4 mmol·h-1·g-1 when employing polylactic acid (PLA) plastic as a sacrificial agent in NaOH solution. The reason behind this can be mainly attributed to the fact that T-CZS consists of wurtzite Cd0.5Zn0.5S (WZ-CZS) and zinc blende Cd0.5Zn0.5S (ZB-CZS) with slight band structure differences, thereby facilitating rapid bulk phase and interface charge separation due to the S-scheme charge transfer routes between WZ-CZS and ZB-CZS, as well as T-CZS and NiCr2O4. Moreover, this system can effectively retain electrons with strong reducing ability for efficient H2 evolution reaction (HER) and generate hot electrons through the localized surface plasmon resonance (LSPR) effect of NiCr2O4, which enhances the absorption of UV-Vis-NIR light energy, thereby facilitating the HER process. What’s more, NaOH solution can indirectly promote the HER kinetics by enhancing the oxidative driving force of holes. Additionally, other metal chromates (MCrxOy), such as CoCr2O4, AgCrO2, Bi6CrO12, BaCrO4, ZnCr2O4, CdCr2O4, CuCr2O4 etc., were employed to enhance the activity of T-CZS too. The results show that above homo-heterojunction composites can integrate waste plastic degradation and photocatalytic H2 evolution effectively based on their S-scheme bulk phase and interface charge separation mechanisms. This work provides new insights into energy and environmental challenges.
The simultaneous enhancement of separation and utilization of bulk and surface charges is crucial for achieving efficient photocatalytic H2 evolution reactions. In this study, NiCr2O4/T-CZS composites were fabricated by incorporating NiCr2O4 nanosheets onto the surface of twinned Cd0.5Zn0.5S (T-CZS) nanoparticles using a solvent evaporation strategy. After optimization, the 6% NiCr2O4/T-CZS exhibited an impressive hydrogen (H2) evolution rate (rH2) of 81.4 mmol·h-1·g-1 when employing polylactic acid (PLA) plastic as a sacrificial agent in NaOH solution. The reason behind this can be mainly attributed to the fact that T-CZS consists of wurtzite Cd0.5Zn0.5S (WZ-CZS) and zinc blende Cd0.5Zn0.5S (ZB-CZS) with slight band structure differences, thereby facilitating rapid bulk phase and interface charge separation due to the S-scheme charge transfer routes between WZ-CZS and ZB-CZS, as well as T-CZS and NiCr2O4. Moreover, this system can effectively retain electrons with strong reducing ability for efficient H2 evolution reaction (HER) and generate hot electrons through the localized surface plasmon resonance (LSPR) effect of NiCr2O4, which enhances the absorption of UV-Vis-NIR light energy, thereby facilitating the HER process. What’s more, NaOH solution can indirectly promote the HER kinetics by enhancing the oxidative driving force of holes. Additionally, other metal chromates (MCrxOy), such as CoCr2O4, AgCrO2, Bi6CrO12, BaCrO4, ZnCr2O4, CdCr2O4, CuCr2O4 etc., were employed to enhance the activity of T-CZS too. The results show that above homo-heterojunction composites can integrate waste plastic degradation and photocatalytic H2 evolution effectively based on their S-scheme bulk phase and interface charge separation mechanisms. This work provides new insights into energy and environmental challenges.
