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Sub-5 nm Ultra-Fine FeP Nanodots as Efficient Co-Catalysts Modified Porous g-C <sub/>3</sub> N <sub/>4</sub> for Precious-Metal-Free Photocatalytic Hydrogen Evolution under Visible Light
摘要： Sub-5 nm ultra-fine iron phosphide (FeP) nano-dots-modified porous graphitic carbon nitride (g-C3N4) heterojunction nanostructures are successfully prepared through the gas-phase phosphorization of Fe3O4/g-C3N4 nanocomposites. The incorporation of zero-dimensional (0D) ultra-small FeP nanodots co-catalysts not only effectively facilitate charge separation but also serve as reaction active sites for hydrogen (H2) evolution. Herein, the strongly coupled FeP/g-C3N4 hybrid systems are employed as precious-metal-free photocatalysts for H2 production under visible-light irradiation. The optimized FeP/g-C3N4 sample displays a maximum H2 evolution rate of 177.9 μmol h?1 g?1 with the apparent quantum yield of 1.57% at 420 nm. Furthermore, the mechanism of photocatalytic H2 evolution using 0D/2D FeP/g-C3N4 heterojunction interfaces is systematically corroborated by steady-state photoluminescence (PL), time-resolved PL spectroscopy, and photoelectrochemical results. Additionally, an increased donor density in FeP/g-C3N4 is evidenced from the Mott-Schottky analysis in comparison with that of parent g-C3N4, signifying the enhancement of electrical conductivity and charge transport owing to the emerging role of FeP. The density functional theory calculations reveal that the FeP/g-C3N4 hybrids could act as a promising catalyst for the H2 evolution reaction. Overall, this work not only paves a new path in the engineering of monodispersed FeP-decorated g-C3N4 0D/2D robust nanoarchitectures but also elucidates potential insights for the utilization of noble-metal-free FeP nanodots as remarkable co-catalysts for superior photocatalytic H2 evolution.
关键词： transition-metal phosphides,g-C3N4,co-catalysts,precious-metal-free,photocatalytic H2 production
更新于2025-09-23 15:23:52
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2D/2D/2D heterojunction of Ti3C2 MXene/MoS2 nanosheets/TiO2 nanosheets with exposed (001) facets toward enhanced photocatalytic hydrogen production activity
摘要： Exposing the highly active facets and hybridizing the photocatalyst with appropriate cocatalysts with right placement have been regarded as a powerful approach to high performance photocatalysts. Herein, TiO2 nanosheets (NSs) are in situ grown on highly conductive Ti3C2 MXene and then MoS2 NSs are deposited on the (101) facets of TiO2 NSs with mainly exposed high-active (001) facets through a two-step hydrothermal method. And a unique 2D-2D-2D structure of Ti3C2@TiO2@MoS2 composite is achieved. With an optimized MoS2 loading amounts (15 wt%), the Ti3C2@TiO2@MoS2 composite shows a remarkable enhancement in the photocatalytic H2 evolution reaction compared with Ti3C2@TiO2 composite and TiO2 NS. It also shows good stability under the reaction condition. This arises from: (i) the in situ growth of TiO2 NSs construct strong interfacial contact with excellent electronic conductivity of Ti3C2, which facilitates the separation of carriers; (ii) the coexposed (101) and (001) facets can form a surface heterojunction within single TiO2 NS, which is beneficial for the transfer and separation of charge carriers; and (iii) the MoS2 NSs are deposited on the electrons-rich (101) facets of TiO2 NSs, which not only effectively reduces the charge carriers recombination rate by capturing photoelectrons, but also makes TiO2 NSs expose more highly active (001) facets to afford high-efficiency photogeneration of electron-hole pairs.
关键词： Exposed active facet,Ti3C2 MXene,TiO2 nanosheets,Photocatalytic H2 production,MoS2 nanosheets
更新于2025-09-23 15:22:29
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Boosting the photocatalytic ability of g-C3N4 for hydrogen production by Ti3C2 MXene quantum dots
摘要： The big challenging issues in photocatalytic H2 evolution are efficient separation of the photoinduced carriers, the stability of the catalyst, enhancing quantum efficiency and requiring photoinduced electrons enrich on photocatalysts’ surface. Herein, Ti3C2 MXene quantum dots (QDs) possess the activity of Pt as co-catalyst in promotion the photocatalytic H2 evolution to form heterostructure with g-C3N4 nanosheets (NSs) (denoted as g-C3N4@Ti3C2 QDs). The photocatalytic H2 evolution rate of g-C3N4@Ti3C2 QDs composite with an optimized Ti3C2 QDs loading amounts (100 mL) is nearly 26, 3 and 10 times higher than pristine g-C3N4 NSs, Pt/g-C3N4, Ti3C2 MXene sheet/g-C3N4, respectively. The Ti3C2 QDs increase the specific surface area of g-C3N4 and boost the density of active site. Besides, metallic Ti3C2 QDs possess excellent electronic conductivity, causing the improvement of carrier transfer efficiency.
关键词： Ti3C2 MXene quantum dots,Photocatalytic H2 production,g-C3N4 nanosheets,co-catalysts
更新于2025-09-19 17:13:59
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Organic blue-colored D-A-??-A dye-sensitized TiO2 for efficient and stable photocatalytic hydrogen evolution under visible/near-infrared-light irradiation
摘要： Photocatalytic splitting of water by titanium dioxide (TiO2) is considered as the most promising approach for the production of hydrogen fuel. However, a low utilization of the solar light spectrum still limits its photoconversion efficiency. Herein, two indeno[1,2-b]thiophene-based organic sensitizers (S5 and S6) are used to sensitize TiO2 to significantly enhance photocatalytic hydrogen production by broadening the spectral response to near-infrared-light region. The results revealed that the average H2 evolution rates of S5@Pt/TiO2 and S6@Pt/TiO2 were 21.5 mmol g-1 h-1 and 7.2 mmol g-1 h-1 , which were 11.3 and 3.9 fold than that of the Pt/TiO2 (1.85 mmol g-1 h-1), respectively. Compared with donor-π-acceptor (D?π?A) dye S6, donor?acceptor?π?acceptor (D-A-π-A) blue-colored dye S5 possesses evident dominant in sensitizing TiO2, in which the auxiliary acceptor 2,3-diphenylquinoxaline (QT) of S5 can effectively disperse donor electron distribution to improve the photo-stability and weak the deprotonation effect to enhance light-harvesting. More importantly, a highly apparent quantum efficiency (AQY) of 2.8% for S5@Pt/TiO2 was obtained at λ = 700 nm monochromatic light, which is, to the best of our knowledge, a recorded value among the pure organic dye-sensitized TiO2 systems. This study offers important insights into the rational design of D-A-π-A organic dye to sensitize TiO2 for highly efficient and stable photocatalytic hydrogen evolution.
关键词： Near-infrared light,Photocatalytic H2 production,D-A-π-A,Blue dye
更新于2025-09-19 17:13:59
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A biomimetic self-assembled cobaloxime@CdS/rGO hybrid for boosting photocatalytic H <sub/>2</sub> production
摘要： A biomimetic CoPe@CdS/rGO hybrid that self-assembles via the integration of a molecular cobalt catalyst and CdS nano-semiconductor on reduced graphene oxide was constructed for boosting photocatalytic H2 production. Photoinduced electron transfer from CdS/rGO to the molecular catalyst occurs and a long-lived charge-separation state forms for high H2 production.
关键词： self-assembled,cobaloxime,CdS/rGO,photocatalytic H2 production,biomimetic
更新于2025-09-12 10:27:22
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Efficient Photocatalytic Hydrogen Production Achieved by WO3 Coupled with NiP2 Over ZIF-8
摘要： The photo-catalyst WO3/NiP2@ZIF-8 was synthesized by modifying the WO3 with NiP2@MOFs structure. High H2 production was achieved (341.2 μmol and 11.3 times than pure WO3 after 5 h) and the catalytic property of WO3 was improved. The XRD, FESEM and TEM were used to characterize and analyze the crystalline phase structure, namely, WO3 has nanowire structure and good crystalline phase, meanwhlie, ZIF-8 exhibits regular dodecahedron morphology. The catalysts were characterized and analyzed by electrochemical, steady-state and transient state, those results show that the composite has more efficient charge separation effect and better electrical performance than single catalyst, which provides a reliable basis for relative higher H2 production activity. The band gap structure and elemental valence of the composite catalysts were calculated and analyzed by UV–Vis DR and XPS, respectively. The possible reaction equation and H2 production mechanism of WO3/NiP2@ZIF-8 in HER were proposed.
关键词： NiP2@ZIF-8,Photocatalytic H2 production,WO3,Band gap structure
更新于2025-09-11 14:15:04
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AgI-BiOI-graphene composite photocatalysts with enhanced interfacial charge transfer and photocatalytic H2 production activity
摘要： BiOI-based photocatalysts were proved to exhibit photocatalytic H2 production activity. AgI-BiOI-graphene showed better H2 production activity than BiOI and BiOI-graphene. The surface chemistry, electronic property, phase structure, morphology, optical property and photocatalytic performance of these photocatalysts were studied. The interfacial electronic states of the photocatalysts were investigated through their C K-edge near-edge X-ray-absorption fine-structure (NEXAFS) spectra. Based on the in situ NEXAFS spectra measured with and without illumination, a mechanism about the transport of photoelectron from AgI to graphene through BiOI is proposed for the photocatalytic H2 production process. The incorporation of graphene restricted the three-dimensional self-assembly of BiOI nanocrystals and led to the formation of less extensively crystallized BiOI domains through a confined-space effect. Addition of AgNO3 precursor altered the crystal structure of BiOI from flower-like to horizontally stacked flat plates. The results of NEXAFS spectra, photoluminescence spectra and photocurrent tests reveal that the improved photocatalytic activity of the AgI-BiOI-graphene photocatalyst is attributable to the interfacial interaction among AgI, BiOI and graphene, which enhanced the separation of photogenerated electrons to generate H2. AgI-BiOI-graphene photocatalyst was a stable photocatalyst for the production of H2. After three cycles, 86 % activity of recycled photocatalysts was retained.
关键词： X-ray absorption spectra,Near edge X-ray absorption fine structure,Interfacial electronic states,Photocatalytic H2 production,BiOI
更新于2025-09-10 09:29:36
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Novel microreactors of polyacrylamide (PAM) CdS microgels for admirable photocatalytic H2 production under visible light
摘要： Cadmium sul?de, with its narrow band gap, can be used as a photocatalyst in the visible light region for the splitting of water, but its limited number of active sites and tendency to agglomerate are problematic for producing high yields of hydrogen. Therefore, an inverse emulsion polymerization method was used to fabricate polyacrylamide (PAM) microgels as a substrate to immobilize CdS nanoparticles (PAM-CdS). The PAM microgels not only immobilized the CdS nanoparticles, but also prevented aggregation. NeCd bonds in the PAM-CdS microgels facilitated electron transfer from the PAM to the CdS resulting in more electrons participating in the H2 production process. The electrostatic interactions between the PAM and CdS also hindered the recombination of electron-hole pairs. These PAM-CdS microgels exhibit admirable photocatalytic H2 production performance with a H2 production rate of up to 5.21 mmol h?1 g?1.
关键词： Visible-light water splitting,PAM microgels,CdS,Photocatalytic H2 production
更新于2025-09-04 15:30:14
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Stable, carrier separation tailorable conjugated microporous polymers as a platform for highly efficient photocatalytic H2 evolution
摘要： The molecular design of highly photo-functional polymers with high charge separation efficiency and wide spectral absorption are long term quest for photocatalysis. Herein, we design and develop a series of nitrogen-containing conjugated microporous polymers (N-CMPs) with tailored donor-acceptor units for enhancing charge separation and light harvesting for visible light photocatalytic H2 production. By alternating the substitution position (o-, m-, or p-) and the number of electron donor (carbazole, diphenylamine) and acceptor (cyano) units on the 3D-core structure, a series of N-CMPs with adjustable donor-acceptor (D-A) charge separation efficiencies and tuneable band gaps in the range of 1.64-2.29 eV were obtained, enabling the precise control of the photocatalytic activity at the molecular level. The optimized N-CMP (4-CzPN) exhibits a higher visible light H2 production rate at 2103.2 μmol/h·g and the apparent quantum yield (AQY) at 420 nm reaches 6.4%. Furthermore, the 4-CzPN photocatalyst maintains excellent durability and recycling performance under 25 h continued light irradiation. The outstanding photocatalytic performance of the optimized N-CMPs with D-A structure is attributed to the enhanced polarity and conjugated degree of their core structure, which promotes charge separation and light absorption.
关键词： light absorption,donor-acceptor units,photocatalytic H2 production,conjugated microporous polymers,charge separation
更新于2025-09-04 15:30:14