Few-Layer MoS2 Nanosheets Encapsulated in N-Doped Carbon Hollow Spheres as Long-Life Anode Materials for Lithium-Ion Batteries

Two-dimensional molybdenum disulfide (MoS₂) has been recognized as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity, but its rapid capacity decay owing to poor conductivity, structure pulverization, and polysulfide dissolution presents significant challenges in practical applications. Herein, triple-layered hollow spheres in which MoS₂ nanosheets are fully encapsulated between inner carbon and outer nitrogen-doped carbon (NC) were fabricated. Such an architecture provides high conductivity and efficient lithium-ion transfer. Moreover, the NC shell prevents aggregation and exfoliation of MoS₂ nanosheets and thus maintains the integrity of the nanostructure during the charge/discharge process. As anode materials for LIBs, the C@MoS₂@NC hollow spheres deliver a high reversible capacity (747 mA h g⁻¹ after 100 cycles at 100 mA g⁻¹) and excellent long-cycle performance (650 mA h g⁻¹ after 1000 cycles at 1.0 A g⁻¹), which confirm its potential for high-performance LIBs.     

Fast electron transfer and enhanced visible light photocatalytic activity by using poly-o-phenylenediamine modified AgCl/g-C3N4 nanosheets

Exfoliation of bulk graphitic carbon nitride (g-C₃N₄) into two-dimensional (2D) nanosheets is one of the effective strategies to improve its photocatalytic properties so that the 2D g-C₃N₄ nanosheets (CN) have larger specific surface areas and more reaction sites. In addition, poly-o-phenylenediamine (PoPD) can improve the electrical conductivity and photocatalytic activity of semiconductor materials. Here, the novel efficient composite PoPD/AgCl/g-C₃N₄ nanosheets was first synthesized by a precipitation reaction and the photoinitiated polymerization approach. The obtained photocatalysts have larger specific surface areas and could achieve better visible-light response. However, silver chloride (AgCl) is susceptible to agglomeration and photocorrosion. The PoPD/AgCl/CN composite exhibits an extremely high photocurrent density, which is three times that of CN. Obviously enhanced photocatalytic activities of PoPD/AgCl/g-C₃N₄ are revealed through the photodegradation of tetracycline. The stability of PoPD/AgCl/CN is demonstrated based on four cycles of experiments that reveal that the degradation rate only decreases slightly. Furthermore, ?O₂^? and h⁺ are the main active species, which are confirmed through a trapping experiment and ESR spin-trap technique. Therefore, the prepared PoPD/AgCl/CN can be considered as a stable photocatalyst, in which PoPD is added as a charge carrier and acts a photosensitive protective layer on the surface of the AgCl particles. This provides a new technology for preparing highly stable composite photocatalysts that can effectively deal with environmental issues.     

Efficient singlet oxygen generation by excitonic energy transfer on ultrathin g-C3N4 for selective photocatalytic oxidation of methyl-phenyl-sulfide with O2

Efficient generation of singlet oxygen (¹O₂) by an excitonic energy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide (MPS). Herein, it is demonstrated that a large amount of ¹O₂ is produced on pristine graphitic carbon nitride (CN) nanosheet compared with bismuth oxybromide (BiOBr) and commercial P25 titanium dioxide (TiO₂). This leads to a certain photoactivity of CN for MPS oxidation. The observed ∼77% selectivity for CN depends on the competitive results of excitonic energy transfer for ¹O₂ formation and charge carrier separation for superoxide radical (O₂⁻) production, which are based on the phosphorescence spectra and electron paramagnetic resonance signals, respectively. Moreover, ultrathin CN nanosheets are synthesized by thermal treatment with the cyanuric acid-melamine hydrogen bonded aggregates as precursors. It is confirmed that the amount of produced ¹O₂ could be increased by decreasing the thickness of resultant CN nanosheets. The optimized ultrathin CN nanosheet (∼4 nm) exhibits excellent photoactivity with high selectivity (∼99%). It is suggested that the excitonic energy transfer for ¹O₂ formation is close related to the intrinsic exciton binding energy and the two-dimensional quantum confinement effect. This work establishes a basic mechanistic understanding on the excitonic processes in CN, and develops a feasible route to design CN-based photocatalysts for efficient ¹O₂ generation.     

Realizing high-efficiency carrier separation in 3D hierarchical carbon nitride nanosheets via intramolecular donor-acceptor motifs strategy

The insufficient visible light responsive region and fast charge recombination probability are still the key obstacles for designing high-performance photocatalytic system. Herein, a “One Stone, Two Birds” strategy was reported in three-dimensional (3D) hierarchical graphitic carbon nitride (g-C₃N₄) nanosheet with intramolecular donor-acceptor (D-A) motifs (3D CN) photocatalyst, which solved two urgent problems simultaneously. The 3D hierarchical nanosheets structure endowed 3D CN with abundantly exposed reaction active sites and cross-plane diffusion channels. The formation of internal D-A system facilitated the light absorption and accelerated the transfer and separation of charge carriers. Furthermore, the introducing of D-A motifs optimized the bandgap of g-C₃N₄ and negative-shifted conduction band position. The as-prepared 3D CN showed excellent visible-light photocatalytic H₂ performance, with H₂ evolution rate of 2521.2 μmol h^?1/g, which was six times higher than the pristine CN. This outstanding performance was ascribed to the synergistic effect of 3D hierarchical nanosheets structure and intramolecular D-A motifs. This current work provides a novel insight to design and construct of 3D hierarchical CN nanostructures with D-A motifs simultaneously, which can be further promising applications for clean and sustainable energy conversion.     

Dual-Templating Approaches to Soybeans Milk-Derived Hierarchically Porous Heteroatom-Doped Carbon Materials for Lithium-Ion Batteries

Biomass derived carbon materials are widely available, cheap and abundant resources. The application of these materials as electrodes for rechargeable batteries shows great promise. To further explore their applications in energy storage fields, the structural design of these materials has been investigated. Hierarchical porous heteroatom-doped carbon materials (HPHCs) with open three-dimensional (3D) nanostructure have been considered as highly efficient energy storage materials. In this work, biomass soybean milk is chosen as the precursor to construct N, O co-doped interconnected 3D porous carbon framework via two approaches by using soluble salts (NaCl/Na₂CO₃ and ZnCl₂/Mg₅(OH)₂(CO₃)₄, respectively) as hard templates. The electrochemical results reveal that these structures were able to provide a stable cycling performance (710 mAh ⋅ g⁻¹ at 0.1 A ⋅ g⁻¹ after 300 cycles for HPHC-a, and 610 mAh ⋅ g⁻¹ at 0.1 A ⋅ g⁻¹ after 200 cycles for HPHC-b) in Li-ion battery and Na-ion storage (210 mAh ⋅ g⁻¹ at 0.1 A ⋅ g⁻¹ after 900 cycles for HPHC-a) as anodes materials, respectively. Further comparative studies showed that these improvements in HPHC-a performance were mainly due to the honeycomb-like structure containing graphene-like nanosheets and high nitrogen content in the porous structures. This work provides new approaches for the preparation of hierarchically structured heteroatom-doped carbon materials by pyrolysis of other biomass precursors and promotes the applications of carbon materials in energy storage fields.     

Defects Promote Ultrafast Charge Separation in Graphitic Carbon Nitride for Enhanced Visible-Light-Driven CO2 Reduction Activity

Fundamental photocatalytic limitations of solar CO₂ reduction remain due to low efficiency, serious charge recombination, and short lifetime of catalysts. Herein, two-dimensional graphitic carbon nitride nanosheets with nitrogen vacancies (g-C₃N_x) located at both three-coordinate N atoms and uncondensed terminal NH_x species were prepared by one-step tartaric acid-assistant thermal polymerization of dicyandiamide. Transient absorption spectra revealed that the defects in g-C₃N₄ act as trapped states of charges to result in prolonged lifetimes of photoexcited charge carriers. Time-resolved photoluminescence spectroscopy revealed that the faster decay of charges is due to the decreased interlayer stacking distance in g-C₃N_x in favor of hopping transition and mobility of charge carriers to the surface of the material. Owing to the synergic virtues of strong visible-light absorption, large surface area, and efficient charge separation, the g-C₃N_x nanosheets with negligible loss after 15 h of photocatalysis exhibited a CO evolution rate of 56.9 μmol g⁻¹ h⁻¹ under visible-light irradiation, which is roughly eight times higher than that of pristine g-C₃N₄. This work presents the role of defects in modulating light absorption and charge separation, which opens an avenue to robust solar-energy conversion performance.     

Ag3PO4/MoS2纳米片复合催化剂制备及可见光催化性能

采用机械球磨法成功制备Ag₃PO₄/MoS₂纳米片复合催化剂。运用X射线衍射仪（XRD）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）、紫外可见漫反射光谱（UV-Vis）和荧光发射光谱（PL）对复合催化剂的结构和形貌进行了表征。结果表明,Ag₃PO₄纳米粒子均匀地附着在MoS₂纳米片层结构上,两者形成紧密结合。以亚甲基蓝为模拟污染物,研究复合催化剂在可见光照射下的光催化特性;通过循环实验考察复合催化剂的稳定性。结果显示,含有1%的MoS₂纳米片与Ag₃PO₄形成的复合催化剂在30 min内对亚甲基蓝的降解率为95%,其降解动力学常数是纯相Ag₃PO₄的2倍。经过5次循环实验后复合催化剂对于亚甲基蓝的降解率为84%,而纯Ag₃PO₄对于亚甲基蓝的降解率仅为35%。Ag₃PO₄/MoS₂纳米片复合催化剂具有优良的光催化活性和高稳定性,主要归因于二硫化钼纳米片与磷酸银形成异质结,磷酸银激发的电子和二硫化钼纳米片产生的空穴直接复合,从而促使光生电子从磷酸银晶体表面快速分离,减轻了磷酸银的光电子腐蚀,同时也提高了复合物的光催化活性。     

β‐Co(OH)2 Nanosheets: A Superior Pseudocapacitive Electrode for High‐Energy Supercapacitors

In this work, β‐Co(OH)₂ nanosheets are explored as efficient pseudocapacitive materials for the fabrication of 1.6 V class high‐energy supercapacitors in asymmetric fashion. The as‐synthesized β‐Co(OH)₂ nanosheets displayed an excellent electrochemical performance owing to their unique structure, morphology, and reversible reaction kinetics (fast faradic reaction) in both the three‐electrode and asymmetric configuration (with activated carbon, AC). For example, in the three‐electrode set‐up, β‐Co(OH)₂ exhibits a high specific capacitance of ∼675 F g⁻¹ at a scan rate of 1 mV s⁻¹. In the asymmetric supercapacitor, the β‐Co(OH)₂∥AC cell delivers a maximum energy density of 37.3 Wh kg⁻¹ at a power density of 800 W kg⁻¹. Even at harsh conditions (8 kW kg⁻¹), an energy density of 15.64 Wh kg⁻¹ is registered for the β‐Co(OH)₂∥AC assembly. Such an impressive performance of β‐Co(OH)₂ nanosheets in the asymmetric configuration reveals the emergence of pseudocapacitive electrodes towards the fabrication of high‐energy electrochemical charge storage systems.     

Fe‐Doped Ni3C Nanodots in N‐Doped Carbon Nanosheets for Efficient Hydrogen‐Evolution and Oxygen‐Evolution Electrocatalysis

Uniform Ni₃C nanodots dispersed in ultrathin N‐doped carbon nanosheets were successfully prepared by carburization of the two dimensional (2D) nickel cyanide coordination polymer precursors. The Ni₃C based nanosheets have lateral length of about 200 nm and thickness of 10 nm. When doped with Fe, the Ni₃C based nanosheets exhibited outstanding electrocatalytic properties for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). For example, 2 at % Fe (atomic percent) doped Ni₃C nanosheets depict a low overpotential (292 mV) and a small Tafel slope (41.3 mV dec⁻¹) for HER in KOH solution. An outstanding OER catalytic property is also achieved with a low overpotential of 275 mV and a small Tafel slope of 62 mV dec⁻¹ in KOH solution. Such nanodot‐incorporated 2D hybrid structures can serve as an efficient bifunctional electrocatalyst for overall water splitting.     

Ag_3PO_4/MoS_2纳米片复合催化剂制备及可见光催化性能

采用机械球磨法成功制备Ag_3PO_4/MoS_2纳米片复合催化剂。运用X射线衍射仪(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、紫外可见漫反射光谱(UV-Vis)和荧光发射光谱(PL)对复合催化剂的结构和形貌进行了表征。结果表明,Ag_3PO_4纳米粒子均匀地附着在MoS_2纳米片层结构上,两者形成紧密结合。以亚甲基蓝为模拟污染物,研究复合催化剂在可见光照射下的光催化特性;通过循环实验考察复合催化剂的稳定性。结果显示,含有1%的MoS_2纳米片与Ag_3PO_4形成的复合催化剂在30 min内对亚甲基蓝的降解率为95%,其降解动力学常数是纯相Ag_3PO_4的2倍。经过5次循环实验后复合催化剂对于亚甲基蓝的降解率为84%,而纯Ag_3PO_4对于亚甲基蓝的降解率仅为35%。Ag_3PO_4/MoS_2纳米片复合催化剂具有优良的光催化活性和高稳定性,主要归因于二硫化钼纳米片与磷酸银形成异质结,磷酸银激发的电子和二硫化钼纳米片产生的空穴直接复合,从而促使光生电子从磷酸银晶体表面快速分离,减轻了磷酸银的光电子腐蚀,同时也提高了复合物的光催化活性。     

Isotypic heterojunction based on Fe-doped and terephthalaldehyde-modified carbon nitride for improving photocatalytic degradation with simultaneous hydrogen production

To achieve an efficient photocatalytic for clean energy production and environmental remediation, the highly active Fe-doped and terephthalaldehyde-modified carbon nitride (Fe-CN/NTE) isotypic heterojunction photocatalyst is constructed via a simple annealing method for degradation of organic pollutants with simultaneous resource recovery. The Fe-CN/NTE catalyst exhibits a 93% removal rate of p-nitrophenol (4-NP) and a 1.72 mmol/g H₂ evolution rate in 2 h simultaneously under visible light irradiation, which are higher than those of pristine CN, Fe-CN, and NTE, respectively. Photoelectrochemical tests show that the excellent photocatalytic performance of Fe-CN/NTE comes from the improved migration, transportation, and separation of photoinduced charge carriers and expanded light-harvesting range. Moreover, hydroxyl radical (OH), electron (e⁻), and hole (h⁺) are the main active species and the rational mechanism of 4-NP photodegradation was proposed based on scavenger measurements and liquid chromatography-mass spectrometry (LC–MS), respectively. Isotypic heterojunction Fe-CN/NTE photocatalyst possesses excellent stability in the H₂ evolution and 4-NP degradation during five-run cycle tests, posing as a promising candidate in practical works for organic pollution and energy challenges.     

Surface-Degenerate Semiconductor Photocatalysis for Efficient Water Splitting without Sacrificial Agents via a Reticular Chemistry Approach

The production of green hydrogen through photocatalytic water splitting is crucial for a sustainable hydrogen economy and chemical manufacturing. However, current approaches suffer from slow hydrogen production (<70 μmol ⋅ g_cat⁻¹ ⋅ h⁻¹) due to the sluggish four-electrons oxygen evolution reaction (OER) and limited catalyst activity. Herein, we achieve efficient photocatalytic water splitting by exploiting a multifunctional interface between a nano-photocatalyst and metal–organic framework (MOF) layer. The functional interface plays two critical roles: (1) enriching electron density directly on photocatalyst surface to promote catalytic activity, and (2) delocalizing photogenerated holes into MOF to enhance OER. Our photocatalytic ensemble boosts hydrogen evolution by ≈100-fold over pristine photocatalyst and concurrently produces oxygen at ideal stoichiometric ratio, even without using sacrificial agents. Notably, this unique design attains superior hydrogen production (519 μmol ⋅ g_cat⁻¹ ⋅ h⁻¹) and apparent quantum efficiency up to 13-fold and 8-fold better than emerging photocatalytic designs utilizing hole scavengers. Comprehensive investigations underscore the vital role of the interfacial design in generating high-energy photoelectrons on surface-degenerate photocatalyst to thermodynamically drive hydrogen evolution, while leveraging the nanoporous MOF scaffold as an effective photohole sink to enhance OER. Our interfacial approach creates vast opportunities for designing next-generation, multifunctional photocatalytic ensembles using reticular chemistry with diverse energy and environmental applications.     

In Situ Anchoring of Pyrrhotite on Graphitic Carbon Nitride Nanosheet for Efficient Immobilization of Uranium

Enrichment of U^VI is an urgent project for nuclear energy development. Herein, magnetic graphitic carbon nitride nanosheets were successfully prepared by in situ anchoring of pyrrhotite (Fe₇S₈) on the graphitic carbon nitride nanosheet (CNNS), which were used for capturing U^VI. The structural characterizations of Fe₇S₈/CNNS-1 indicated that the CNNS could prevent the aggregation of Fe₇S₈ and the saturation magnetization was 4.69 emu g⁻¹, which meant that it was easy to separate the adsorbent from the solution. Adsorption experiments were performed to investigate the sorption properties. The results disclosed that the sorption data conformed to the Langmuir isotherm model with the maximum adsorption capacity of 572.78 mg g⁻¹ at 298 K. The results of X-ray photoelectron spectroscopy (XPS) demonstrated that the main adsorption mechanism are as follows: U^VI is adsorbed on the surface of Fe₇S₈/CNNS-1 through surface complexation initially, then it was reduced to insoluble U^IV. Thereby, this work provided an efficient and easy to handle sorbent material for extraction of U^VI.     

Sulfur-Induced Growth of Coordination Polymer Derived-Straight Carbon Nanotubes on Carbon Nanofiber Network for Zn-Air Batteries

Low-cost heteroatom-doped carbon nanomaterials have been widely studied for efficient oxygen reduction reaction and energy storage and conversion in metal-air batteries. A Masson pine twigs-like 3-dimensional network construction of carbon nanofibers (CNFs) with abundant straight long Co, N, and S-doped carbon nanotubes (CNTs) is developed by thermal treatment of Co-based polymer coated onto polyacrylonitrile nanofiber network together with thiourea at 900 °C, denoted as CNFT-Co₉S₈-900. It is interesting to note that the introduction of a high concentration of sulfur does not lead to the complete toxicity of catalysts, but promotes the axial growth to selectively form straight CNTs instead of curly bamboo-like CNTs. The highly graphitized in-situ grown Co, N, S-doped CNTs and the 3-dimensional N-doped CNF network provide both active catalytic sites and highly conductive paths, which are beneficial for oxygen reduction reaction (ORR). Thus, the optimal CNFT-Co₉S₈-900 performs the excellent ORR catalytic activity with a half-wave potential of 0.84 V and a diffusion-limited current density of 5.49 mA cm⁻². Furthermore, the CNFT-Co₉S₈-900-based Zn-air devices also possess a high power density of 136.9 mW cm⁻² better than commercial Pt/C.     

Preparation of Hierarchical Porous Activated Carbon from Banana Leaves for High-performance Supercapacitor: Effect of Type of Electrolytes on Performance

We demonstrate a facile efficient way to fabricate activated carbon nanosheets (ACNSs) consisting of hierarchical porous carbon materials. Simply heating banana leaves with K₂CO₃ produce ACNSs having a unique combination of macro-, meso- and micropores with a high specific surface area of ∼1459 m² g⁻¹. The effects of different electrolytes on the electrochemical supercapacitor performance and stability of the ACNSs are tested using a two-electrode system. The specific capacitance (C_sp) values are 55, 114, and 190 F g⁻¹ in aqueous 0.5 M sodium sulfate, organic 1 M tetraethylammonium tetrafluoroborate in acetonitrile, and pure ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF₆]) electrolytes, respectively. The ACNSs also shows the largest potential window of 3.0 V, the highest specific energy (59 Wh kg⁻¹) and specific power (750 W kg⁻¹) in [BMIM][PF₆]. A mini-prototype device is prepared to demonstrate the practicality of the ACNSs.     

Harvesting Solar Light with Crystalline Carbon Nitrides for Efficient Photocatalytic Hydrogen Evolution

Described herein is the photocatalytic hydrogen evolution using crystalline carbon nitrides (CNs) obtained by supramolecular aggregation followed by ionic melt polycondensation (IMP) using melamine and 2,4,6‐triaminopyrimidine as a dopant. The solid state NMR spectrum of ¹⁵N‐enriched CN confirms the triazine as a building unit. Controlling the amount and arrangements of dopants in the CN structure can dramatically enhance the photocatalytic performance for H₂ evolution. The polytriazine imide (PTI) exhibits the apparent quantum efficiency (AQE) of 15 % at 400 nm. This method successfully enables a substantial amount of visible light to be harvested for H₂ evolution, and provides a promising route for the rational design of a variety of highly active crystalline CN photocatalysts.     

A Fully Conjugated Covalent Organic Framework with Oxidative and Reductive Sites for Photocatalytic Carbon Dioxide Reduction with Water

Constructing a powerful photocatalytic system that can achieve the carbon dioxide (CO₂) reduction half-reaction and the water (H₂O) oxidation half-reaction simultaneously is a very challenging but meaningful task. Herein, a porous material with a crystalline topological network, named viCOF-bpy-Re, was rationally synthesized by incorporating rhenium complexes as reductive sites and triazine ring structures as oxidative sites via robust −C=C− bond linkages. The charge-separation ability of viCOF-bpy-Re is promoted by low polarized π-bridges between rhenium complexes and triazine ring units, and the efficient charge-separation enables the photogenerated electron–hole pairs, followed by an intramolecular charge-transfer process, to form photogenerated electrons involved in CO₂ reduction and photogenerated holes that participate in H₂O oxidation simultaneously. The viCOF-bpy-Re shows the highest catalytic photocatalytic carbon monoxide (CO) production rate (190.6 μmol g⁻¹ h⁻¹ with about 100 % selectivity) and oxygen (O₂) evolution (90.2 μmol g⁻¹ h⁻¹) among all the porous catalysts in CO₂ reduction with H₂O as sacrificial agents. Therefore, a powerful photocatalytic system was successfully achieved, and this catalytic system exhibited excellent stability in the catalysis process for 50 hours. The structure–function relationship was confirmed by femtosecond transient absorption spectroscopy and density functional theory calculations.     

An Unlocked Two-Dimensional Conductive Zn-MOF on Polymeric Carbon Nitride for Photocatalytic H2O2 Production

Developing highly efficient catalytic sites for O₂ reduction to H₂O₂, while ensuring the fast injection of energetic electrons into these sites, is crucial for artificial H₂O₂ photosynthesis but remains challenging. Herein, we report a strongly coupled hybrid photocatalyst comprising polymeric carbon nitride (CN) and a two-dimensional conductive Zn-containing metal–organic framework (Zn-MOF) (denoted as CN/Zn-MOF(lc)/400; lc, low crystallinity; 400, annealing temperature in °C), in which the catalytic capability of Zn-MOF(lc) for H₂O₂ production is unlocked by the annealing-induced effects. As revealed by experimental and theoretical calculation results, the Zn sites coordinated to four O (Zn-O₄) in Zn-MOF(lc) are thermally activated to a relatively electron-rich state due to the annealing-induced local structure shrinkage, which favors the formation of a key *OOH intermediate of 2e⁻ O₂ reduction on these sites. Moreover, the annealing treatment facilitates the photoelectron migration from the CN photocatalyst to the Zn-MOF(lc) catalytic unit. As a result, the optimized catalyst exhibits dramatically enhanced H₂O₂ production activity and excellent stability under visible light irradiation.     

Carbon Quantum Dot Implanted Graphite Carbon Nitride Nanotubes: Excellent Charge Separation and Enhanced Photocatalytic Hydrogen Evolution

Graphite carbon nitride (g‐C₃N₄) is a promising candidate for photocatalytic hydrogen production, but only shows moderate activity owing to sluggish photocarrier transfer and insufficient light absorption. Herein, carbon quantum dots (CQDs) implanted in the surface plane of g‐C₃N₄ nanotubes were synthesized by thermal polymerization of freeze‐dried urea and CQDs precursor. The CQD‐implanted g‐C₃N₄ nanotubes (CCTs) could simultaneously facilitate photoelectron transport and suppress charge recombination through their specially coupled heterogeneous interface. The electronic structure and morphology were optimized in the CCTs, contributing to greater visible light absorption and a weakened barrier of the photocarrier transfer. As a result, the CCTs exhibited efficient photocatalytic performance under light irradiation with a high H₂ production rate of 3538.3 μmol g^?1 h^?1 and a notable quantum yield of 10.94 % at 420 nm.     

Ultrathin Niobate Nanosheet Assembly with Au NPs and CdS QDs as a Highly Efficient Photocatalyst

Niobate nanosheets have aroused widespread interest in recent years for their prospects in catalysis. The exploration of 2D niobate catalysis with stable and efficient properties is still the focus in chemistry and materials science. Herein, the successful fabrication of 2D CdS/Au/HNb₃O₈ catalyst is demonstrated which revealed efficient photocatalytic properties in H₂ evolution, oxidative self-coupling of amines to imines, and degradation of dyes. Especially the assembled architecture can give a rate of 5.85 mmol ⋅ g⁻¹ ⋅ h⁻¹ of photocatalytic H₂ evolution, an ∼254-fold enhancement, compared with bare HNb₃O₈ nanosheets under identical conditions. In accordance with density functional theory (DFT) and X-ray adsorption fine structure (XAFS) analyses, the vast improvements are benefited from efficient migration and separation of charge carriers. Besides, the surface plasma resonance (SPR) effect of Au NPs enhances the light harvesting capacity and boosts the generation of hot electrons, efficiently improving the visible-light absorption.