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g-C3N4 nanosheets functionalized silicon nanowires hybrid photocathode for efficient visible light induced photoelectrochemical water reduction
摘要： We report the fabrication of hybrid Si nanowires @ g-C3N4 nanosheets based photocathode using metal assisted chemical etching and facile liquid exfoliated process. The g-C3N4 nanosheets on Si nanowires form hybrid heterojunction photocathode, which exhibits an enhanced photon induced water reduction activity enabling higher photocurrent density of 22 mA cm?2 with applied bias photocurrent conversion efficiency of 4.3% under visible light irradiation. The onset potential of cathodic photocurrent is positively shifted from 41 to 420 mV vs. RHE with the short circuit current density, Jsc of 0.50 mA cm?2 owing to superior charge transport in hybrid photocathode as compared to pristine Si nanowires for hydrogen evolving reaction at pH～7. The electrochemical impedance spectroscopy measurement elucidates the interface layer of g-C3N4 nanosheets form hybrid heterojunction with Si nanowires that result significant increment in solar water reduction activity owing to low charge transferred resistance with high life time of excited electrons in conduction band. This strategy may open to design a new low cost stable hybrid heterostructure photocathode for solar induced water reduction.
关键词： Solar water reduction,Si nanowires,Photocathode,g-C3N4 nanosheets,Interface
更新于2025-11-21 11:01:37
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G‐C3N4‐SiC‐Pt for Enhanced Photocatalytic H2 Production from Water under Visible Light Irradiation
摘要： The g-C3N4 and SiC has drawn increasing attention for application to visible light photocatalytic hydrogen evolution from water splitting due to their unique band structure and high physicochemical stability. In this study, g-C3N4-SiC heterojunction with loaded noble metal was constructed. The g-C3N4-SiC-Pt composite photocatalysts were successfully prepared by the combination method of a bio-reduction, sol-deposition and calcination. The layers of g-C3N4 were thinned and the SiC and Pt nanoparticles simultaneously were tightly bound to g-C3N4 by calcination in the process of preparing the g-C3N4-SiC-Pt. The heterojunction formed in the interface of SiC and g-C3N4 enhances the separation efficiency of the photogenerated electron-hole pairs. These composite photocatalysts achieve a high hydrogen evolution rate of 595.3 μmol·h-1·g-1 with a 1wt% of deposited Pt, 3.7- and 2.07-fold higher than g-C3N4-bulk and g-C3N4-SiC under visible-light irradiation with a quantum efficiency of 2.76% at 420 nm, respectively.
关键词： visible light,g-C3N4-SiC-Pt photocatalysts,hydrogen evolution,photocatalysis
更新于2025-11-21 11:01:37
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Synergistic effect of g-C3N4, Ni(OH)2 and halloysite in nanocomposite photocatalyst on efficient photocatalytic hydrogen generation
摘要： Here, we develop a strategy to improve the visible-light-driven photocatalytic hydrogen evolution activity of g-C3N4 by compositing it with low-cost Ni(OH)2 nanoplatelets and inexpensive and earth-abundant halloysite nanotubes. The Ni(OH)2@g-C3N4/halloysite nanocomposite photocatalyst with different amounts of Ni(OH)2 (0.5–10 wt%) were prepared, and a synergistic effect of Ni(OH)2 platelets and halloysite nanotubes on physicochemical properties and photocatalytic hydrogen evolution activity of g-C3N4 was investigated. As expected, the Ni(OH)2@g-C3N4/halloysite nanocomposite photocatalyst prepared with 1 wt% Ni(OH)2 exhibited the highest photocatalytic hydrogen evolution rate (18.42 μmol·h–1) which is much higher than that of g-C3N4 (0.43 μmol·h–1) and Ni(OH)2@g-C3N4 (9.12 μmol·h–1). Such enhancement in photocatalytic activity of Ni(OH)2@g-C3N4/halloysite nanocomposite photocatalyst is attributed to efficient transfer of photogenerated electrons from the g-C3N4 to Ni(OH)2 cocatalyst interface and trapping of photogenerated holes on the negatively charged surfaces of halloysite nanotubes. In addition, adsorption affinity of the water and methanol molecules was modeled using different surfaces of Ni(OH)2, halloysite-7?, and g-C3N4 and it is found that combining the g-C3N4 with halloysite-7? and Ni(OH)2 can significantly improve the adsorption of water and methanol molecules on the surface of the developed nanocomposite. This study offers a simple approach for developing an efficient and inexpensive nanocomposite for effective and applied photocatalytic water splitting methodology for hydrogen production and other possible optoelectronic and photocatalytic applications.
关键词： Halloysite,g-C3N4,Water splitting,Nanocomposite,Hydrogen production,Ni(OH)2
更新于2025-11-19 16:51:07
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Efficient visible light-driven hydrogen generation on g-C3N4 coupled with iron phosphide
摘要： Transition metal phosphides as promising noble-metal-free cocatalysts are gaining increasing interest for hydrogen generation and other energy conversion reactions. Herein, the present study reports a new Fe2P/g-C3N4 hybrid for efficient photocatalytic hydrogen generation by water splitting under visible light irradiation, whose H2 production rate is ~15 times higher than that of pure g-C3N4, and is comparable with that of Pt/g-C3N4 at the same condition. According to the detailed analyses of UV-vis diffuse reflectance, photoluminescence spectra, and photoelectrochemical measurements, the reason for the high efficiency of Fe2P/g-C3N4 hybrid is due to highly effective separation and low recombination rate of photo-generated electrons and holes rather than absorption light. The present study shows a promising photocatalyst with non-toxicity, low cost, and natural abundance for improving photocatalytic H2 generation.
关键词： photocatalysis,g-C3N4,hydrogen generation,noble metal-free,Fe2P
更新于2025-11-19 16:51:07
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Constructing electrostatic self-assembled 2D/2D ultra-thin ZnIn2S4/protonated g-C3N4 heterojunctions for excellent photocatalytic performance under visible light
摘要： 2D/2D ultra-thin ZnIn2S4/protonated g-C3N4 nanocomposites (ZnIn2S4/pCN) are fabricated by electrostatic self-assembly strategy between negatively charged 2D ultra-thin ZnIn2S4 nanosheets and 2D protonated g-C3N4 nanosheets. The optimized ZnIn2S4/pCN (5:3) shows excellent photocatalytic activity toward H2 production (~8601.16 μmol·g?1·h?1) under visible light. In addition, ZnIn2S4/pCN also exhibits superior visible-light-driven photocatalytic tetracycline degradation efficiency, about ~4.13 and ~2.28 times higher than protonated g-C3N4 and ultra-thin ZnIn2S4, respectively. The optimal ZnIn2S4/pCN (5:3) also has good photostability. The excellent photocatalytic activity of ZnIn2S4/pCN can be attributed to the unique 2D/2D heterojunctions, which are obtained by electrostatic self-assembly. The intimate interfacial contact and larger contact areas promote the separation and migration of photogenerated carriers, which contribute to the improvement of photocatalytic activity and photostability. Our research on the 2D/2D nanocomposites provides a scalable solution for the research of efficient and active photocatalysts.
关键词： protonated g-C3N4,ultra-thin ZnIn2S4 nanosheets,electrostatic self-assembly,2D/2D
更新于2025-11-19 16:46:39
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Constructing highly dispersed 0D Co3S4 quantum dots/2D g-C3N4 nanosheets nanocomposites for excellent photocatalytic performance
摘要： Herein, 0D metal sulfide quantum dots/2D g-C3N4 nanosheets (Co3S4/CNNS) nanocomposites are synthesized by a two-step method, including the ways of in-situ deposition and water bath. The highly dispersed Co3S4 quantum dots (particle size is 2-4 nm) are evenly and tightly fixed on CNNS, which can be used as co-catalyst to effectively replace noble metals to improve the photocatalytic properties of CNNS. Co3S4/CNNS-900 has the apparent quantum efficiency, which is up to 7.85 % at 400 nm. At the same times, the H2 evolution rate of Co3S4/CNNS-900 is 20536.4 μmol·g-1·h-1, which is 555 times than CNNS.
关键词： g-C3N4,photocatalysis,Co3S4
更新于2025-11-19 16:46:39
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In suit inducing electron-donating and electron-withdrawing groups in carbon nitride by one-step NH4Cl-assisted route: A strategy for high solar hydrogen production efficiency
摘要： Owing to insu?cient active sites, strongly bound excitons and insu?cient optical absorption, polymer semiconductors have only shown mild activity as potential candidates for photocatalysis. A g-C3N4 with improved optical absorption capacity, charge transfer performance and porosity was successfully prepared by a one-step NH4Cl-assisted route. Interaction of melamine with NH4Cl preparation of Porous g-C3N4(CN-xy) with active functional groups modi?ed pore wall shown to result in highly crystalline species with a maximum π-π layer stacking distance of heptazine units of 0.321 nm, decreases the optical band gap from 2.80 to 2.13 eV and maximum surface area reached 56.485 m2 g?1. The balanced improvement of the multiple defects of g-C3N4 makes the photocatalytic degradation of RhB and the photocatalytic hydrogen production e?ciency 4 and 5 times higher than the pristine g-C3N4, respectively.
关键词： Photocatalytic,g-C3N4,Porous,Trade-o?,Active functional groups
更新于2025-11-19 16:46:39
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A high-performance photocatalyst of ZnTCPP sensitized porous graphitic carbon nitride for antibiotic degradation under visible light irradiation
摘要： In this paper, a highly efficient photocatalyst of ZnTCPP sensitized g-C3N4 was successfully constructed via a facile thermal polycondensation method. The FT-IR and XRD data indicated that ZnTCPP molecules were successfully condensed on the surface of g-C3N4 through amide groups as the bridging units. The optimum 10%ZnTCPP/g-C3N4 composites exhibits excellent enhanced photocatalytic activity for decomposing both methylene blue (MB) and tetracycline (TC) under visible light with long-term reusability and elimination rates of 96% and 80.3%, respectively. The superior visible light photocatalytic performance was mainly attributed to the highly efficient separation of electron-hole pairs and the enhanced solar light utilization, as demonstrated by photoluminescence (PL), electrochemical impedance spectra (EIS), photocurrent responses, and UV-vis diffuse reflectance spectroscopy (DRS). The active species trapping and terephthalic acid (TA) fluorescence experiments indicated that ·OH was the dominating reactive oxidizing species for TC degradation. Furthermore, the possible photocatalytic degradation pathways for MB and TC have been proposed based on the UPLC-MS spectrometry. The excellent degradation efficiency of ZnTCPP/g-C3N4 reveals that it has great potential as photocatalysts for practical application to eliminate recalcitrant organic contaminants.
关键词： Zn meso-tetra (4-carboxyphenyl) porphyrin,Tetracycline,Photocatalyst,Semiconductors,g-C3N4
更新于2025-11-19 16:46:39
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Binary composites WO3/g-C3N4 in porous morphology: Facile construction, characterization, and reinforced visible light photocatalytic activity
摘要： Various WO3/g-C3N4 binary composites were constructed by a facile one-step calcination procedure and then systematically analyzed for chemophysical properties. Interestingly, these resultant composites showed porous morphology in combination with some tubular structures, where both components were closely contacted to generate heterojunction structures. Accordingly, these composites possessed reinforced visible-light absorption capability and enlarged specific surface areas in texture. These microstructural, morphological, and electronic merits ensured the strengthened photocatalytic performance toward degradation of rhodamine B (RhB) and methylene blue (MB) under visible light irradiation. In addition, on base of reactive species entrapping experiments and analytical results, a probable photocatalysis mechanism was speculated as a “Z-scheme” manner instead of conventional Type II path.
关键词： WO3,Photocatalytic degradation,Mechanism,Porous morphology,Binary composites,g-C3N4
更新于2025-11-14 17:04:02
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Photoelectrochemical biosensor for microRNA detection based on a MoS2/g-C3N4/black TiO2 heterojunction with Histostar@AuNPs for signal amplification
摘要： Herein, a novel photoelectrochemical (PEC) biosensor was developed for the ultrasensitive detection of microRNA-396a based on a MoS2/g-C3N4/black TiO2 heterojunction as the photoactive material and gold nanoparticles carrying Histostar antibodies (Histostar@AuNPs) for signal amplification. Briefly, MoS2/g-C3N4/black TiO2 was deposited on an indium tin oxide (ITO) electrode surface, after which gold nanoparticles (AuNPs) and probe DNA were assembled on the modified electrode. Hybridization with miRNA-396a resulted in a rigid DNA:RNA hybrid being formed, which was recognized by the S9.6 antibody. The captured antibody can further conjugate with the secondary IgG antibodies of Histostar@AuNPs, thereby leading to the immobilization of horse radish peroxidase (HRP). In the presence of HRP, the oxidation of 4-chloro-1-naphthol (4-CN) by H2O2 was accelerated, producing the insoluble product benzo-4-chlorohexadienone on the electrode surface and causing a significant decrease in the photocurrent. The developed biosensor could detect miRNA-396a at concentrations from 0.5 fM to 5000 fM, with a detection limit of 0.13 fM. Further, the proposed method can also be used to investigate the effect of heavy metal ions on the expression level of miRNAs. Results suggest that the biosensor developed herein offers a promising platform for the ultrasensitive detection of miRNA.
关键词： S9.6 antibody,Histostar@AuNPs,MicroRNA detection,MoS2/g-C3N4/black TiO2 heterojunction,Photoelectrochemical biosensor
更新于2025-11-14 17:04:02