Photocatalytic H2 Production Activity Research Articles

Facile preparation of carbon nitride by binary eutectic KNO3/KCl molten salt and its photocatalytic performance evaluation

A facile molten salt-assisted heat-treated carbon nitride via binary eutectic KNO3/KCl was successfully developed. The as-prepared photocatalyst had much improved photocatalytic activity for organic matter photodegradation and H2 production.

Enhanced photocatalytic hydrogen production activity of Ni modified TiO2/GO nanosheet composites

Ni modified TiO2/GO nanosheet composites were prepared using a hydrothermal method, and exhibited an enhanced photocatalytic H2-production activity.

Plasma surface treatment facilitated visible light-driven H2 production over TiO2

TiO2 precursors were treated by plasma technology in three atmospheres (N2, Ar, H2). Interstitial N-doping can be facilely realized in N2 atmosphere, the light absorption range of N2-TiO2 is enlarged, and the surface oxygen vacancies (OVs) are significantly increased. Surface OVs enhance the efficient separation of photogenerated e−/h+ pairs in TiO2. The microscopic oxide layer on the surface of TiO2 is destroyed, bringing about Ti3+ defects and formation of more surface OVs in H2 and Ar atmosphere. Ti3+ defects, high concentration of surface OVs and the Ti3+-OVs defect energy level significantly reduce the photogenerated electron excitation energy. The photocatalytic H2 production activity of TiO2 treated via plasma technique in the different atmospheres was evaluated under visible light irradiation. Consequently, the H2 production efficiency on N2-TiO2 is 103.6 umolh−1 g−1, which is 2.1 times, 1.6 times, and 1.3 times of that on the pristine TiO2, H2-TiO2, and Ar-TiO2, respectively. The apparent quantum efficiency (AQE) of H2 generation on N2-TiO2 is 0.08%, which is 1.6 times of that over the reference TiO2 under 420 nm monochromatic light irradiation. The photocatalytic mechanisms for H2 production over all the photocatalysts were discussed according to a series of characterizations.

Boosting interfacial S-scheme charge transfer and photocatalytic H2-production activity of 1D/2D WO3/g-C3N4 heterojunction by molecular benzene-rings integration

A novel benzene-ring engineered 1D/2D WO3/g-C3N4 S-scheme photocatalyst (BCNW) was rationally designed and successfully synthesized by the electrostatic self-assembly method. Experimental and Density Functional Theory results reveal that the integration of molecular benzene-ring in the framework of g-C3N4 can not only narrow its bandgap and accelerate charge separation by forming a mid-state at the top of its valence band but more importantly open up a new additional bridge for speeding up the interfacial S-scheme charge transfer in BCNW. Benefitting from those multiple positive effects of benzene-ring integration, as expected, BCNW S-scheme photocatalysts show superior photocatalytic H2-production activity and reach 2971 μmol h–1 g–1 under visible-light illumination, which is 3.35 times WO3/g-C3N4 S-scheme photocatalyst without benzene-ring integration. This work supplies an innovative strategy for the design of a high-efficiency S-scheme photocatalytic system by constructing a facile and additional molecular charge transfer channel at the interface.

Surface-dependent properties and morphological transformations of rutile GeO2 nanoparticles

Recently, the knowledge of surface-dependent properties has attracted a lot of attention since it is crucial for materials functionalization based on the morphological control of nanoparticles (NPs). This study describes the surface-dependent properties and morphological transformation routes of rutile germanium dioxide (r-GeO2) using the density functional theory (DFT) and the Wulff construction procedure. The calculations revealed the following order of relative surface stability: (110) > (100) > (321) > (311) > (201) > (211) > (101) > (103) > (001) > (111), with the Ge-O bonds being attributed to Ge4p-O2p and Ge4s-O2p interactions. The results demonstrate that the different coordination breakages on the outermost polyhedra are related to atomic charges, band gap, relative stability, and Fermi energy. Additionally, a map of the morphological transformation routes and the band alignment were elaborated, showing that cubic, octahedral, or hexadecahedral morphologies can have photocatalytic activity for H2 production via water splitting. The methodology and results reported herein can help target the synthesis and functionalization of rutile-type materials.

Rational design and fabrication of MoSx nanoclusters decorated Mn0.3Cd0.7S nanorods with promoted interfacial charge transfer toward robust photocatalytic H2 generation

In this work, we report a novel MoSx/Mn0.3Cd0.7S composite catalyst that has been designed and fabricated by in situ coupling MoSx nanoclusters with 1D Mn0.3Cd0.7S nanorods for photocatalytic H2 production. The catalyst features a 1D nanostructure with MoSx nanoclusters uniformly dispersed along the Mn0.3Cd0.7S nanorod. It was found that an intimate interface is built between MoSx nanoclusters and Mn0.3Cd0.7S nanorods thanks to the facile in situ photoreduction route, which contributes to a high-efficiency interfacial charge separation. The resulting MoSx/Mn0.3Cd0.7S photocatalyst shows a dramatically enhanced visible-light-driven photocatalytic H2 production activity compared with the control samples, owing to more efficient spatial charge separation as well as enriched active sites. This work is expected to provide an optimized structure model for rational design and constructing novel, inexpensive, efficient and stable cocatalyst/metal sulfide photocatalyst systems for H2 production.

Synergism between nitrogen vacancies and a unique electrons transfer pathway of Ag modified S-scheme g-C3N4/CdS heterojunction for efficient H2 evolution

Ag modified g-C3N4/CdS (Ag@g-C3N4/CdS) S-scheme heterojunction with a distinctive charge transfer channel was prepared as a photocatalyst for photoreduction of H2O. The effect of nitrogen vacancies and photo-excited charge carriers in the water splitting on the Ag@g-C3N4/CdS was discussed. It was found that the charge carriers transport channel in Ag@g-C3N4/CdS S-scheme heterojunction was instrumental in the enhancement of H2 production. The electrons in Ag nanospheres and in the conduction band (CB) of CdS can recombine with the holes in the valence band (VB) of g-C3N4, which prolonged the lifetime of electrons in the CB of g-C3N4. Meanwhile, a unique charge transfer channel was produced in the Ag@g-C3N4/CdS. Compared with g-C3N4, Ag@g-C3N4/CdS photocatalyst demonstrated an enhanced performance which was assigned to the increased charge carrier lifetime. The supreme Ag@g-C3N4/CdS showed photocatalytic H2 production activity up to 204.19 μmol for 4 h under illuminate (λ ≥ 420 nm), which was 11.74 times than that of g-C3N4.

Peanut-chocolate-ball-inspired construction of the interface engineering between CdS and intergrown Cd: Boosting both the photocatalytic activity and photocorrosion resistance

Interface engineering can improve the charge separation efficiency and inhibit photocorrosion is an emerging direction of developing more efficient and cost-effective photocatalytic systems. Herein, we report the sulfur-confined intimate CdS intergrown Cd (CdS/Cd) Ohmic junction (peanut-chocolate-ball like) for high-efficient H2 production with superior anti-photocorrosion ability, which was fabricated from in-situ photoreduction of CdS intergrown Cd2SO4(OH)2 (CdS/Cd2SO4(OH)2) prepared through a facile space-controlled-solvothermal method. The ratios of CdS/Cd can be effectively controlled by tunning that of CdS/Cd2SO4(OH)2 which were prepared by adjusting the volume of reaction liquid and the remaining space of the reactor. Experiments investigations and density functional theory (DFT) calculations reveal that the CdS intergrown Cd Ohmic junction interfaces (with appropriate content Cd intergrown on CdS (19.54 wt%)) are beneficial in facilitating the transfer of photogenerated electrons by constructing an interfacial electric field and forming sulfur-confined structures for preventing the positive holes (h+) oxidize the CdS. This contributes to a high photocatalytic H2 production activity of 95.40 μmol h−1 (about 32.3 times higher than bare CdS) and possesses outstanding photocatalytic stability over 205 h, much longer than most CdS-based photocatalysts previously reported. The interface engineering design inspired by the structure of peanut-chocolate-ball can greatly promote the future development of catalytic systems for wider application.

Visible light activated MoS2/ZnO composites for photocatalytic degradation of ciprofloxacin antibiotic and hydrogen production

In the photocatalysis process, photon energy is mainly converted into chemical energy with the help of both light and catalyst. This process can be used in different applications like photocatalytic degradation of hazardous compounds, fixation of nitrogen, hydrogen production, air purification, water splitting, carbon dioxide reduction etc. In this research work, multiplicative ZnO and MoS2/ZnO (MZ) composites were synthesized using green chemical methods like the hydrothermal process and used in two different applications i) photocatalytic degradation of ciprofloxacin (CIP) antibiotic and ii) hydrogen production. CIP is not easily biodegradable and is mainly used in various antibacterial treatments. The photocatalytic activity was tested for ZnO and different MoS2/ZnO composites along with this the effect of different amounts of catalysts doses was studied. MoS2/ZnO composites exhibit superior photocatalytic performance than ZnO for photocatalytic degradation of CIP. Using the LC-MS technique possible degradation pathways are proposed. The same photocatalyst materials were used to test the photocatalytic H2 production activity. H2 production rates were found to be 22, 39 and 235 µmol/g/h for ZnO, MoS2 and MZ-30 composite respectively. Superior photocatalytic activity of MZ-30 composite than ZnO is chiefly attributed to the extended light absorption capacity, effective charge transfer, suitable band alignment between the ZnO and MoS2, minimum recombination of charge carriers etc.

Facile in-situ synthesis of α-NiS/CdS p-n junction with enhanced photocatalytic H2 production activity

Constructing active sites on photocatalysts is one of the most effective approaches for promoting photocatalytic H2 production activity. In this paper, a p-type semiconductor α-NiS is in-situ grown on an n-type semiconductor CdS by a simple solid state method, which results in a strong interfacial contact between α-NiS and CdS. Benefitting from the built-in electric field caused by a p-n junction, the photoinduced electrons of CdS and holes of α-NiS migrate to their interface and recombine rapidly, which results in the formation of a Z system. The more negative CB potential of α-NiS/CdS possesses stronger ability to reduce H+ to H2, thereby exhibiting higher photocatalytic H2 evolution activity. Furthermore, the strong interface contact is beneficial to the charge migration and promotes the charge separation efficiency. The H2 evolution rate of 1.0% α-NiS/CdS reaches 9.8 mmol h−1 g−1, corresponding to an AQY of 65.7% at λ = 420 nm.

Au@Cu2O Core–Shell and Au@Cu2Se Yolk–Shell Nanocrystals as Promising Photocatalysts in Photoelectrochemical Water Splitting and Photocatalytic Hydrogen Production

In this work, we demonstrated the practical use of Au@Cu2O core-shell and Au@Cu2Se yolk-shell nanocrystals as photocatalysts in photoelectrochemical (PEC) water splitting and photocatalytic hydrogen (H2) production. The samples were prepared by conducting a sequential ion-exchange reaction on a Au@Cu2O core-shell nanocrystal template. Au@Cu2O and Au@Cu2Se displayed enhanced charge separation as the Au core and yolk can attract photoexcited electrons from the Cu2O and Cu2Se shells. The localized surface plasmon resonance (LSPR) of Au, on the other hand, can facilitate additional charge carrier generation for Cu2O and Cu2Se. Finite-difference time-domain simulations were carried out to explore the amplification of the localized electromagnetic field induced by the LSPR of Au. The charge transfer dynamics and band alignment of the samples were examined with time-resolved photoluminescence and ultraviolet photoelectron spectroscopy. As a result of the improved interfacial charge transfer, Au@Cu2O and Au@Cu2Se exhibited a substantially larger photocurrent of water reduction and higher photocatalytic activity of H2 production than the corresponding pure counterpart samples. Incident photon-to-current efficiency measurements were conducted to evaluate the contribution of the plasmonic effect of Au to the enhanced photoactivity. Relative to Au@Cu2O, Au@Cu2Se was more suited for PEC water splitting and photocatalytic H2 production by virtue of the structural advantages of yolk-shell architectures. The demonstrations from the present work may shed light on the rational design of sophisticated metal-semiconductor yolk-shell nanocrystals, especially those comprising metal selenides, for superior photocatalytic applications.

Anion-Cation Co-Doped g-C3N4 Porous Nanotubes with Efficient Photocatalytic H2 Evolution Performance.

Graphitic C3N4-based materials are promising for photocatalytic H2 evolution applications, but they still suffer from low photocatalytic activity due to the insufficient light absorption, unfavorable structure and fast recombination of photogenerated charge. Herein, a novel anion–cation co-doped g-C3N4 porous nanotube is successfully synthesized using a self-assembly impregnation-assisted polymerization method. Ni ions on the surface of the self-assembly nanorod precursor can not only cooperate with H3P gas from the thermal cracking of NaH2PO2 as an anion–cation co-doping source, but, more importantly, suppress the shape-collapsing effect of the etching of H3P gas due to the strong coordinate bonding of Ni-P, which leads to a Ni and P co-doped g-C3N4 porous nanotube (PNCNT). Ni and P co-doping can build a new intermediate state near the conduction band in the bandgap of the PNCNT, and the porous nanotube structure gives it a higher BET surface area and light reflection path, showing a synergistic ability to broaden the visible-light absorption, facilitate photogenerated charge separation and the light-electron excitation rate of g-C3N4 and provide more reaction sites for photocatalytic H2 evolution reaction. Therefore, as expected, the PNCNT exhibits an excellent photocatalytic H2 evolution rate of 240.91 μmol·g−1·h−1, which is 30.5, 3.8 and 27.8 times as that of the pure g-C3N4 nanotube (CNT), single Ni-doped g-C3N4 nanotube (NCNT) and single P-doped g-C3N4 nanotube (PCNT), respectively. Moreover, the PNCNT shows good stability and long-term photocatalytic H2 production activity, which makes it a promising candidate for practical applications.

Metal Complex/ZnS-Modified Ni Foam as Magnetically Stirrable Photocatalysts: Roles of Redox Mediators and Carrier Dynamics Monitored by Operando Synchrotron X-ray Spectroscopy.

Magnetically stirrable photocatalysts binding the ZnS-decorated Ni foam with the metal complex cocatalyst as a redox mediator and light-absorbing composition were investigated. Loading metal complex can improve light absorption, surface hydrophilicity, interfacial charge migration, and H2 production activity. The variation of the metal valences of the composite photocatalysts in an operando environment (with sacrificial agent solution) with and without light irradiation was investigated by X-ray absorption near-edge structure (XANES) spectra and Fourier-transformed extended X-ray absorption fine structure (EXAFS) spectra to monitor the charge carrier dynamics of photocatalysis and explain how the macrocyclic Cu complex (CuC) acted as a redox mediator better than the Ni complex. The smaller valence difference of copper valence in ZS/CuC for dark and light states revealed that the Cu complex facilitates a reversible electron transfer between the ZnS photocatalyst and H+. Loading the Cu complex can improve the separation of photogenerated carriers by the redox couple of complexes, leading to a significantly improved photocatalytic H2 production activity of 8150 μmol h-1 g-1. The reactants can flow through these magnetically stirrable Ni foam-based photocatalysts by magnetic-field-driven stirring, which improves the contact between photocatalysts and the sacrificial agents. The operando synchrotron provides new insights for understanding the roles of redox mediators.

Optimizing hydrogen adsorption of NixB cocatalyst by integrating P atom for enhanced photocatalytic H2-production activity of CdS

Developing low-cost and long-lasting nickel boride (NixB) for hydrogen evolution reaction is desirable to favor the present renewable energy system. However, H atom adsorption on Ni active site is weakened by the electron transfer from B to Ni atom in NixB, causing the inhibited hydrogen-evolution process. Herein, the metalloid P is introduced into NixB to regulate the electron density of Ni active site, with the aim of enhancing its H atom adsorption to boost the photocatalytic H2-production activity of CdS. In this regard, the NixPB cocatalysts with a size of 8–10 nm are loaded on reduced graphene oxide (rGO) to produce NixPB-rGO cocatalyst, which was well coupled with CdS to prepare the NixPB-rGO/CdS photocatalyst. Photocatalytic hydrogen-evolution tests suggested that the NixPB-rGO/CdS photocatalyst displayed the highest H2-evolution rate of 5.79 mmol h−1 g−1, which is 1.8 and 9.9 times over the NixB-rGO/CdS and rGO/CdS photocatalysts, respectively. The above improved activity of NixPB-rGO/CdS photocatalyst can be attributed to the promoting hydrogen adsorption of Ni atom for efficient interfacial H2 production via the facile introduction of P heteroatom. This work provides a feasible strategy to optimize the transition metal borides cocatalysts for the photocatalytic H2 evolution.

Construction and performance of CdS/MoO2@Mo2C-MXene photocatalyst for H2 production

Nowadays, photocatalytic technologies are regarded as promising strategies to solve energy problems, and various photocatalysts have been synthesized and explored. In this paper, a novel CdS/MoO2@Mo2C-MXene photocatalyst for H2 production was constructed by a two-step hydrothermal method, where MoO2@Mo2C-MXene acted as a binary co-catalyst. In the first hydrothermal step, MoO2 crystals with an egged shape grew on the surface of two-dimensional (2D) Mo2C MXene via an oxidation process in HCl aqueous solution. In the second hydrothermal step, CdS nanorods were uniformly assembled on the surface of MoO2@Mo2C-MXene in ethylenediamine with an inorganic cadmium source and organic sulfur source. The CdS/MoO2@Mo2C-MXene composite with MoO2@Mo2C-MXene of 5 wt% exhibits an ultrahigh visible-light photocatalytic H2 production activity of 22,672 µmol/(g·h), which is ∼21% higher than that of CdS/Mo2C-MXene. In the CdS/MoO2@Mo2C-MXene composite, the MoO2 with metallic nature separates CdS and Mo2C MXene, which acts as an electron-transport bridge between CdS and Mo2C MXene to accelerate the photoinduced electron transferring. Moreover, the energy band structure of CdS was changed by MoO2@Mo2C-MXene to suppress the recombination of photogenerated carriers. This novel compound delivers upgraded photocatalytic H2 evolution performance and a new pathway of preparing the low-cost photocatalyst to solve energy problems in the future.

Photochemistry of ZnO/GeO2 film for H2 production

In this study, ZnO/GeO2 compound was prepared by the sol-gel method and deposited onto ITO conductive glass substrate (Indium Tin Oxide) and non-conductive glass by spin coating technique to be used as active materials for H2 generation by means of photoelectrochemical and photocatalytic processes. Films were characterized by X-ray diffraction, which crystallized in ZnO type-structure. By UV-Vis tests, films showed an improvement in the light absorption and a shift towards the visible spectrum; Eg value of ZnO/GeO2 is slightly lower than ZnO value (3.15 vs. 3.25 eV, respectively). PL analysis exhibited a lower intensity of ZnO/GeO2 curve than ZnO, indicating low electron-hole pair recombination. ZnO/GeO2 films presented spherical grains and high roughness as revealed by AFM micrographs, which is beneficial to increase the number of active sites on the surface and reduces the light scattering for better catalytic performance. Photoelectrochemical characterization demonstrates that ZnO/GeO2 showed excellent photocurrent response due to the better charge transfer, low resistance and low impedance observed in the Nyquist curves and Bode diagrams, as well as an increase in donor density as Mott-Schottky measurements indicated. In this case, ZnO/GeO2 film generates five times higher photocurrent than ZnO under solar light simulated (0.5 vs. 0.1 mA/cm2). Furthermore, Incident Photon to Current Conversion Efficiency (IPCE) for ZnO/GeO2 was 63% at 350 nm in wavelength. The Solar-To-Hydrogen (STH) conversion for ZnO/GeO2 was six times higher than ZnO (0.24 vs. 0.04%, respectively). This conversion is due to the presence of GeO2, which is causing a lower depletion layer, favoring minor recombination of the electron-hole pair in the semiconductor. On the other hand, photocatalytic activity for H2 production showed a 6-fold increase for ZnO/GeO2 (31.6 vs 5.6 µmol H2, respectively). The presence of GeO2 increases the number of active sites, and the hole-electron pair separation, avoiding photocorrosion, a common problem for ZnO. Then, ZnO/GeO2 film could be a promising candidate for H2 generation under photoinduced processes.

Visible-light photocatalytic oxygen production on a high-entropy oxide by multiple-heterojunction introduction

High-entropy oxides (HEOs), as multi-component ceramics with high configurational entropy, have been of recent interest due to their attractive properties including photocatalytic activity for H2 production and CO2 conversion. However, the photocatalytic activity of HEOs is still limited to ultraviolet light. In this study, to achieve visible-light-driven photocatalysis, 10 different heterojunctions were simultaneously introduced in the Ti-Zr-Nb-Ta-W-O system. The oxide, which was synthesized by a high-pressure torsion method and oxidation, successfully produced oxygen from water under visible light without co-catalyst addition. The photocatalytic performance was attributed to high visible-light absorption, low bandgap, appropriate band structure, presence of multiple heterojunctions and accordingly easy electron-hole separation and slow recombination. These results not only show the potential of high-entropy oxides as new visible-light-active photocatalysts, but also introduce the multiple-heterojunction introduction as a strategy to achieve photocatalysis under visible light.

Facile one‐pot pyrolysis preparation of SnO2/g‐C3N4 composites for improved photocatalytic H2 production

AbstractBACKGROUNDGraphitic carbon nitride (g‐C3N4) has attracted extensive attention as a typical photocatalyst. However, g‐C3N4 still needs to be modified to obtain enhanced hydrogen production activity.RESULTSHere, SnO2/g‐C3N4 composites were prepared by a facile one‐pot pyrolysis method, and showed enhanced visible‐light‐driven photocatalytic H2 production activities with the highest value of 241 μmol h−1 g−1, which was about four times that of pure polymeric g‐C3N4. The facile one‐pot pyrolysis method not only promoted effective coupling between g‐C3N4 and SnO2, but also adjusted the photocatalytic performance‐related physicochemical properties of polymeric g‐C3N4. The reduction of particle sizes of g‐C3N4 promoted the migration of photogenerated carriers to the surface and the introduction of SnO2 as electron transport material promoted the transfer of photogenerated charge carriers from g‐C3N4 host photocatalyst to metallic Pt cocatalyst, synergistically restraining the recombination of photogenerated carriers. Moreover, the increased specific surface areas and pore volumes enriched the reactive sites and facilitated the mass transfer of reactants, thus accelerating the redox reactions. Furthermore, the enhanced light absorption promoted the generation of photogenerated carriers which was beneficial for photocatalytic reactions.CONCLUSIONSThis work provides an effective reference for the application of Sn species in the modification of photocatalysts, especially polymeric g‐C3N4. © 2022 Society of Chemical Industry.

Carbohydrate-regulated synthesis of ultrathin porous nitrogen-vacancy polymeric carbon nitride for highly efficient Visible-light hydrogen evolution

Morphologies and electronic structures of the photocatalysts play a critical role in governing their photocatalytic actives via providing large specific surface area (more active sites) and suitable band structure. To achieve high visible-light photocatalytic activity, herein, an ultrathin porous nitrogen-vacancy polymeric carbon nitride (PCN) was synthesized by high-temperature thermal polymerization using melamine with a biomass derived carbohydrate aqueous solution, offering a flexible nature to finely tune the vacant and porous structures through properly changing the carbohydrate. The ultrathin porous structure could significantly enhance the specific surface area of PCN and improve the mobility of charges. Moreover, the induced vacancies structures could largely expand the light absorption range and reduce the recombination rate of photogenerated carriers. These led to an excellent photocatalytic activity for H2 production, with the optimal hydrogen evolution rate 17.2 times (5.5 mmol h−1 g−1, 1 wt.% Pt as a co-catalyst) higher than that of the unmodified PCN (0.32 mmol h−1 g−1). These results provide a simple, effective, and cost-effective strategy for the synthesis of novel photocatalysts using biomass-based raw materials to obtain a highly active photocatalyst with simultaneous adjusting the vacancies and porous structures.

Investigation of Photo(electro)catalytic water splitting to evolve H2 on Pt-g-C3N4 nanosheets

g-C3N4 has shown great potentials in photocatalytic water splitting to produce hydrogen. Herein, we successfully synthesized g-C3N4 nanosheets via exfoliating bulk g-C3N4. And different metal nanoparticles were photo-deposited onto the surface of g-C3N4 nanosheets. The photocatalytic H2 production activity of g-C3N4 nanosheets increased from 0 to 11.2 μmol/h/gcat. The Pt loaded g-C3N4 nanosheets manifested the highest H2 production activity with a rate of 589.4 μmol/h/gcat. In addition, the hydrogen evolution rate was further enhanced with addition of external bias to fabricate a photoelectrocatalytic (PEC) system. And the maximum hydrogen production rate (23.1 mmol/h/m2) was obtained at a voltage of 0.6 V (vs. Ag/AgCl). The enhancement in H2 production may be due to the following reasons: (1) Two-dimensional atomic flakes is beneficial to increase the specific surface area of g-C3N4, enhance the mobility of carriers, and improve the energy band structure, (2) Pt nanoparticles play an important role in g-C3N4 electron transport, (3) the g-C3N4 nanosheets loaded with Pt nanoparticles exhibited significant enhancement in photoelectrocatalytic performance, which may be attributed to its enhanced electronic conductivity and photoelectrochemical surface area, (4) Pt inhibited the recombination of photogenerated carriers and significantly improved the photocatalytic performance. The enhancement mechanism was deeply discussed and explained in this work.