Surface oxygen vacancy facilitated Z-scheme MoS2/Bi2O3 heterojunction for enhanced visible-light driven photocatalysis-pollutant degradation and hydrogen production

An oxygen-vacancy rich, bismuth oxide (Bi₂O₃) based MoS₂/Bi₂O₃ Z-scheme heterojunction catalyst (2-BO-MS) was prepared in an autoclave hydrothermal method using ethanol and water. The performance of MoS₂/Bi₂O₃ catalyst was examined for photocatalytic hydrogen evolution, photoelectrochemical activity, and crystal violet (CV) dye degradation by comparing with pristine Bi₂O₃ and MoS₂. The hydrogen evolution performances of 2-BO-MS catalyst exhibited 3075.21 μmol g⁻¹ h⁻¹, which is 7.18 times higher than that of MoS₂ (428.14 μmol g⁻¹ h⁻¹). The XPS, XRD and HRTEM analyses covered that the superior photocatalytic performance of 2-BO-MS catalyst might have stemmed out due to the existence of oxygen vacancies, enhanced strong interfacial interaction between MoS₂ and Bi₂O₃ and specific surface area. The in-depth investigation has been performed for MoS₂/Bi₂O₃ Z-scheme heterojunction using several characterization techniques. Moreover, the photocatalytic mechanism for hydrogen evolution and photodegradation were proposed based on trapping experiment results. This results acquired using MoS₂/Bi₂O₃ Z-scheme heterojunction would be stepping stone for developing heterojunction catalyst towards attaining outstanding photocatalytic activity.     

Highly efficient Bi2O3/MoS2 p-n heterojunction photocatalyst for H2 evolution from water splitting

The design of p-n heterojunction photocatalysts to overcome the drawbacks of low photocatalytic activity that results from the recombination of charge carriers and narrow photo-response range is promising technique for future energy. Here, we demonstrate the facile hydrothermal synthesis for the preparation of Bi₂O₃/MoS₂ p-n heterojunction photocatalysts with tunable loading amount of Bi₂O₃ (0–15 wt%). The structure, surface morphology, composition and optical properties of heterostructures were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV–visible absorption spectroscopy, Brunauer-Emmett-Teller (BET) surface area, photoluminescence (PL), electrochemical impedance spectroscopy (EIS). Compare to pure Bi₂O₃ and MoS_2, the Bi₂O₃/MoS₂ heterostructures displayed significantly superior performance for photocatalytic hydrogen (H₂) production using visible photo-irradiation. The maximum performance for hydrogen evolution was achieved over Bi₂O₃/MoS₂ photocatalyst (10 μmol h⁻¹g⁻¹) with Bi₂O₃ content of 11 wt%, which was approximately ten times higher than pure Bi₂O₃ (1.1 μmol h⁻¹g⁻¹) and MoS₂ (1.2 μmol h⁻¹g⁻¹) photocatalyst. The superior performance was attributed to the robust light harvesting ability, enhanced charge carrier separation via gradual charge transferred pathway. Moreover, the increased efficiency of Bi₂O₃/MoS₂ heterostructure photocatalyst is discussed through proposed mechanism based on observed performance, band gap and band position calculations, PL and EIS data.     

MoS2/Ti3C2 heterostructure for efficient visible-light photocatalytic hydrogen generation

The MoS₂/Ti₃C₂ catalyst with a unique sphere/sheet structure were prepared by hydrothermal method. The MoS₂/Ti₃C₂ heterostructure loading 30% Ti₃C₂ has a maximum hydrogen production rate of 6144.7  μmol g⁻¹ h⁻¹, which are 2.3 times higher than those of the pure MoS₂. The heterostructure maintains a high catalytic activity within 4 cycles. The heterostructure not only effectively reduce the recombination of photogenerated electrons and holes, but also provide more activation sites, which promotes the photocatalytic hydrogen evolution reaction (HER). These works can provide reference for the development of efficient catalysts in photocatalytic hydrogen evolution.     

An efficient ternary Mn0.2Cd0.8S/MoS2/Co3O4 heterojunction for visible-light-driven photocatalytic H2 evolution

An efficient ternary Mn_0.2Cd_0.8S/MoS₂/Co₃O₄ heterojunction was prepared and displayed excellent photocatalytic performance. The ternary Mn_0.2Cd_0.8S/MoS₂/Co₃O₄ heterojunction with 0.62 wt% of MoS₂ and 1.51 wt% of Co₃O₄ achieved the highest H₂ evolution activity (16.45 mmol g⁻¹ h⁻¹), which was well above Mn_0.2Cd_0.8S (2.72 mmol g⁻¹ h⁻¹). The improved H₂ evolution activity was ascribed to the synergistic effect of the Mn_0.2Cd_0.8S/Co₃O₄ p–n heterojunction and the modification of MoS₂ as a co-catalyst. This work can offer a new perspective for the application of Mn_xCd_1−xS-based ternary heterojunction towards solar energy conversion.     

Interface engineering of the NiCo2O4@MoS2/TM heterostructure to realize the efficient alkaline oxygen evolution reaction

Electrochemical water splitting is considered as a promising strategy for the efficient hydrogen production, yet it is hindered by the sluggish oxygen evolution reaction (OER). Herein, heterostructure OER catalyst is fabricated by combining MoS₂ nanosheets with NiCo₂O₄ hollow sphere on Ti mesh. Benefiting from the heterogeneous nanointerface between NiCo₂O₄ and MoS₂, this electrocatalyst demonstrates excellent OER activity in basic environment with overpotentials of 313 and 380 mV achieving 10 and 100 mA cm⁻². The superb catalytic performance stems from hollow the nanostructure and interfacial engineering strategy that enhance intrinsic activity and provide faster charge transfer. Hence, this work provides a feasible path for exploiting the high-efficient catalysts.     

A novel approach for high-yield solid few-layer MoS2 nanosheets with effective photocatalytic hydrogen evolution

Few-layer molybdenum disulfide (MoS₂) nanosheets are well applied in many field, but the lack of simple methods for the preparation of solid few-layer MoS₂ nanosheets with high yield and quality has greatly restricted their development. In this work, a facile solvothermal treatment coupled with the liquid exfoliation strategy was conducted to produce solid monodispersed few-layer MoS₂ nanosheets from the MoS₂ stack, and the output can reach as high as approximately 0.3 g/g. The few-layer features were confirmed by characterizations of SEM, TEM, Raman spectra, UV–vis absorption spectrum and PL spectrum. The obtained MoS₂ nanosheets exhibit fantastic dispersity and stability in an NMP solution, which can remain uniform even after one year. In general, pure MoS₂ catalysts show no or poor activity for photocatalytic hydrogen evolution as reported in the literature, however, the prepared MoS₂ nanosheets in this work display excellent photocatalytic H₂ evolution performance of 1241.3 μmol g⁻¹ h⁻¹ due to the synergistic structural and electronic modifications, including a bigger specific surface area, additional exposed active edge sites, superior charge separation and transfer efficiency, and higher reduction potential.     

Phase controlled synthesis and the phase dependent photo-and electrocatalysis of CdS@CoMo2S4/MoS2 catalyst for HER

Herein we report a heterostructure with ultrathin nanosheets of Co-doped molybdenum sulfide on CdS nanorod array (donated as CdS@CoMo₂S₄/MoS₂) by hydrothermal synthesis. Firstly, elemental Co doping MoS₂ (CoMo₂S₄) delivers the double benefits of increased active sites and enhanced conductivity. Secondly, the structural characteristics maximally exposes the MoS₂ edges and enlarges interfacial contact area between the composite catalyst and electrolyte, as well as the efficient interfacial charge transfer. The ratio of CoMo₂S₄/MoS₂ in CdS@CoMo₂S₄/MoS₂ plays a crucial role for the enhanced photo-assistant electrocatalytic hydrogen evolution reaction (HER). We can tune the ratio of CoMo₂S₄/MoS₂ by controlling the preparation time or the ratio of precursor of Co/Mo. The catalyst with predominant MoS₂ phase shows superior photocatalytic HER performance with a high H₂ production rate of 46.60 μmol mg⁻¹ h⁻¹. Meanwhile, the catalyst with predominant CoMo₂S₄ phase exhibits not only relatively low overpotential of 172 mV at 10 mA cm⁻², which outperforms most values that have been reported on catalyst supported on ITO substrate, but also possesses H₂ production rate of 23.47 μmol mg⁻¹ h⁻¹. The superior photo-assistant electrocatalytic HER activity results from the synergistically structural and electronic modulations, as well as the proper energy band alignment between MoS₂ and CdS. This investigation could provide an approach to integrate the electro- and photocatalytic activities for HER, especially the photo responding behaviour at a bias potential which is meaningful to produce H₂ for actual application.     

g-C3N4/CoAl-LDH 2D/2D hybrid heterojunction for boosting photocatalytic hydrogen evolution

In this work, a 2D/2D heterojunction composed of CoAl layered double hydroxide (LDH) and graphitic carbon nitride nanosheets (CNNS) was designed and fabricated for boosting photocatalytic hydrogen generation. The as-prepared 20 mol% CoAl-LDH/CNNS exhibited a remarkable photocatalytic hydrogen evolution rate of 680.13 μmol h⁻¹ g⁻¹, which was 21 times higher than that of pure CoAl-LDH (32.91 μmol h⁻¹ g⁻¹). The enhanced activity could be mainly attributed to its unique structure and high surface area. Distinct from ordinary heterojunction photocatalysts, two-dimensional (2D) heterojunctions with abundant 2D coupling interfaces and strong interfacial interaction could efficiently suppress the recombination of photo-induced charge carriers and shorten charge transmission distance. Particularly, compared with other concentrations, the increased surface area (138.70 m² g⁻¹) of 20 mol% CoAl-LDH/CNNS, which is 3.94 times of pure CNNS (35.48 m² g⁻¹), is more favorable for enhanced photocatalytic activity. Increasing the surface area of sheet-on-sheet heterostructure is an effective and novel strategy to facilitate the photocatalytic hydrogen evolution from water splitting.     

Ultrathin MoS2 nanosheets in situ grown on rich defective Ni0.96S as heterojunction bifunctional electrocatalysts for alkaline water electrolysis

Developing earth-abundant and highly active bifunctional electrocatalysts are critical to advance sustainable hydrogen production via alkaline water electrolysis but still challenging. Herein, heterojunction hybrid of ultrathin molybdenum disulfide (MoS₂) nanosheets and non-stoichiometric nickel sulfide (Ni_0.96S) is in situ prepared via a facile one-step hydrothermal strategy, followed by annealing at 400 °C for 1 h. Microstructural analysis shows that the hybrid is composed of intimate heterojunction interfaces between Ni_0.96S and MoS₂ with exposed active edges provided by ultrathin MoS₂ nanosheets and rich defects provided by non-stoichiometric Ni_0.96S nanocrystals. As expected, it is evaluated as bifunctional electrocatalysts to produce both hydrogen and oxygen via water electrolysis with a hydrogen evolution reaction (HER) overpotential of 104 mV at 10 mA cm⁻² and an oxygen evolution reaction (OER) overpotential of 266 mV at 20 mA cm⁻² under alkaline conditions, outperforming most current noble-metal-free electrocatalysts. This work provides a simple strategy toward the rational design of novel heterojunction electrocatalysts which would be a promising candidate for electrochemical overall water splitting.     

Carbon intercalated MoS2 cocatalyst on g-C3N4 photo-absorber for enhanced photocatalytic H2 evolution under the simulated solar light

Despite MoS₂ being a promising non-precious-metal cocatalyst, poor electronic conductivity and low activity for hydrogen evolution caused by serious agglomeration have been identified as critical roadblocks to further developing MoS₂ cocatalyst for photocatalytic water splitting using solar energy. In this work, the density functional theory calculations reveal that carbon intercalated MoS₂ (C-MoS₂) has excellent electronic transport properties and could effectively improve catalytic activity. The experiment results show that the prepared tremella-like C-MoS₂ nanoparticles have large interlayer spacing along the c-axis direction and high dispersion because of intercalation of the carbon between adjacent MoS₂ layers. Furthermore, the heterostructure photocatalyst of C-MoS₂@g-C₃N₄ formed by loading the cocatalyst of C-MoS₂ onto g-C₃N₄ nanosheets exhibits the H₂ evolution rate of 157.14 μmolg⁻¹h⁻¹ when containing 5 wt% C-MoS₂. The high photocatalytic H₂ production activity of the 5 wt% C-MoS₂@g-C₃N₄ can be attributed to the intercalated conductive carbon layers in MoS₂, which leads to efficient charge separation and transfer as well as increased activities of the edge S atoms for H₂ evolution. We believe that the C-MoS₂ will offer great potential as a photocatalytic H₂ evolution reaction cocatalyst with high efficiency and low cost.     

Enhanced visible-light-assisted photocatalytic hydrogen generation by MoS2/g-C3N4 nanocomposites

A facile, one-pot, solvothermal synthesis of MoS₂ microflowers (S1) and the heterostructures MoS₂/g-C₃N₄ with varying ratios of 1:1 (S2), 1:2 (S3) and 1:3 (S4) exhibiting enhanced visible-light-assisted H₂ generation by water splitting has been reported. The compounds were thoroughly characterized by PXRD, FESEM, HRTEM, EDS, UV–vis and XPS techniques. FESEM and HRTEM analyses showed the presence of microflowers composed of nano-sized petals in case of pure MoS₂ (S1), while the MoS₂ microflowers covered with g-C₃N₄ nanosheets in case of MoS₂/g-C₃N₄ heterostructure, S4. XPS analysis of S2 showed the presence of 2H phase of MoS₂ with g-C₃N₄. The Eosin-Y/dye-sensitized visible-light-assisted photocatalytic investigation of the samples in the absence of any noble metal co-catalyst revealed very good water splitting activity of MoS₂/g-C₃N₄ heterostructure, S2 with hydrogen generation rate of 1787 μmol h⁻¹g⁻¹ which is about 6 and 40 times higher than pure MoS₂ and g-C₃N₄ respectively. The relatively higher catalytic activity of the heterostructure, S2 has been ascribed to the efficient spatial separation of photo-induced charge carriers owing to the synergistic interaction between MoS₂ and g-C₃N₄. A possible mechanism for the Eosin-Y-sensitized photocatalytic H₂ generation activity of MoS₂/g-C₃N₄ heterostructures has also been presented. The enhanced activity of S2 was further supported by fluorescence measurements. Thus, the present study highlights the importance of non-noble metal based MoS₂/g-C₃N₄ heterojunction photocatalysts for efficient visible-light-driven H₂ production from water splitting.     

Efficient and long-term photocatalytic H2 evolution stability enabled by Cs2AgBiBr6/MoS2 in aqueous HBr solution

Lead-free Cs₂AgBiBr₆ (CABB) double perovskite as a new-type photocatalytic material alternative to lead halide perovskites holds promise to implement the solar-H₂ conversion, but the interior recombination of photo-generated carriers and thus low photocatalytic hydrogen evolution reaction (HER) rate of CABB restrict its further industrial applications. Herein, we report the composite fabrication of MoS₂/CABB heterostructure for high-efficiency and durable photocatalytic HER by anchoring non-noble MoS₂ onto CABB via a facile dissolution-recrystallization method. The optimized MoS₂/CABB performs a visible-light HER rate of 87.5 μmol h^?1 g^?1 in aqueous HBr solution, ca. 20-fold compared to that of pure CABB (4.3 μmol h^?1 g^?1), and presents a discontinuous 500-h photocatalytic HER stability with no evident loss. The superb performance of MoS₂/CABB can be ascribed to the kinetics-facilitated heterostructure consisting of stable CABB and MoS₂. This work proposes a facile and versatile tactic to construct a low-cost Cs₂AgBiBr₆-based heterostructure for efficient and long-term photocatalytic HER.     

2D MOFs enriched g-C3N4 nanosheets for highly efficient charge separation and photocatalytic hydrogen evolution from water

Here we report a 2D-2D heterostructure of g-C₃N₄/UMOFNs photocatalysts via mechanical grinding two kinds of two-dimensional nanosheets of g-C₃N₄ nanosheets and UMOFNs, which exhibits enhanced H₂ evolution from water with simulated solar irradiation. g-C₃N₄ nanosheets are in close contact with UMOFNs, and there is a certain interaction between them, showing the effect of superimposition on the two-dimensional layer. The 2D-2D heterostructure offers a maximal photocatalytic hydrogen production activity of 1909.02 μmol g⁻¹ h⁻¹ with 3 wt% of UMOFNs, which is 3-fold higher than that of g-C₃N₄ nanosheets (628.76 μmol g⁻¹ h⁻¹) and 15-flod higher than that of bulk g-C₃N₄ (124.30 μmol g⁻¹ h⁻¹). The significant increasement of photocatalysis is due to 2D-2D heterostructure possessing a short charge transfer distance and large contact area between g-C₃N₄ and UMOFNs. The highly dispersed NiO, CoO and π-π bonds in UMOFNs of 2D-2D structure also promote charge transfer and enhance the photocatalytic activity.     

ZnIn2S4 nanosheets decorating WO3 nanorods core-shell hybrids for boosting visible-light photocatalysis hydrogen generation

We here report the fabrication of a core-shell WO₃@ZnIn₂S₄ heterostructure by an interfacial seeding growth strategy, which is implemented by direct growth of ZnIn₂S₄ nanosheets on the surface of WO₃ nanorods with forming a strong electronic interaction between two semiconductors that are beneficial for promoting the interfacial charge transfer. Systematic studies demonstrate that the WO₃@ZnIn₂S₄ nanohybrids hold superior performance for photocatalytic hydrogen generation under visible light irradiation with a production rate of 3900 μmol g⁻¹ h⁻¹. This work provides an effective approach to construct the direct Z-scheme photocatalytic systems for efficient photocatalytic hydrogen evolution, which would be significant for the design of more direct Z-scheme system for various photocatalytic applications.     

Design and fabrication of hollow structured Cu2MoS4/ZnIn2S4 nanocubes with significant enhanced photocatalytic hydrogen evolution performance

The unique architecture is very significant for photocatalysts to achieve high photocatalytic efficiency. Herein, hollow Cu₂MoS₄/ZnIn₂S₄ heterostructural nanocubes with intimate-contact interface have been prepared for the first time via a self-template way, which can promote the photocatalysis hydrogen evolution. First, novel hollow structured Cu₂MoS₄ nanocubes were successfully synthesized using Cu₂O as a precursor, then the ZnIn₂S₄ nanosheets were in-situ grew on the surface of hollow Cu₂MoS₄ nanocubes. The unique hollow heterostructures have markedly enhanced photocatalytic efficiency, and 15 wt% Cu₂MoS₄/ZnIn₂S₄ sample exhibits the highest hydrogen production rate of 8103 μmol·h⁻¹·g⁻¹, which is approximately four times higher than pure ZnIn₂S₄. The improved photocatalytic performance is mainly attributed to the following two points: (1) the hollow nanocube structure can provide rich active sites and increase light absorption; (2) forming a built-in electric field is conducive to transfer the holes generated by ZnIn₂S₄ to Cu₂MoS₄, which can effectively promote charge separation. This work may provide insights for the design of hollow architecture cage materials for high photocatalytic performance.     

A novel Z-type multidimensional FeSe2/CuSe heterojunction photocatalyst with high photocatalytic and photoelectrochemical performance

A novel Z-type multidimensional FeSe₂/CuSe heterojunction photocatalyst was synthesized by a hydrothermal progress. In the reaction, 1D FeSe₂ nanorods will load on the surface of 2D CuSe nanosheets to construct heterojunction. This Z-type heterojunction can improve the carriers separated efficiency and reduce internal resistance (as low as 0.31 kΩ). More importantly, the catalysts display both high oxidation and reduction ability confirmed by photocatalytic and photoelectrochemical test. Under the optimum concentration, the catalyst showed 7.4 times of degradation tetracycline hydrochloride rate, and 4 times of photocurrent density than pure CuSe. Active specie O₂^?? was detected by the electron spin resonance tool during photocatalytic degradation progress which could confirm that a Z-type heterojunction was constructed between CuSe and FeSe₂. In this Z-type heterojunction, photoinduced electrons in the conduction band of FeSe₂ can directly inject the valence band of CuSe while photoinduced electrons in the conduction band position of CuSe and photoinduced holes in the valence band position of FeSe₂ will remain. The remained photoinduced electrons in the conduction band of CuSe can generate O₂^?? to oxide tetracycline hydrochloride as well as photoinduced electrons to produce hydrogen. This work highlights a simple strategy of Z-tpye selenides heterostructure for oxidation and reduction application.     

Hydrogen generation by photocatalytic reforming of glucose with heterostructured CdS/MoS2 composites under visible light irradiation

A binary heterostructured CdS/MoS₂ flowerlike composite photocatalysts was synthesized via a simple one-pot hydrothermal method. This photocatalyst demonstrated higher photocatalytic hydrogen production activity than pure MoS₂. The heterojunction formed between MoS₂ and CdS seems to promote interfacial charge transfer (IFCT), suppress the recombination of photogenerated electron–hole pairs, and enhance the hydrogen generation. Based on the good match between the conduction band (CB) edge of CdS and that of MoS₂, electrons in the CB of CdS can be transferred to MoS₂ easily through the heterojunction between them, which prevents the accumulation of electrons in the CB of CdS, inhibiting photocorrosion itself and greatly enhancing stability of catalyst. Hydrogen evolution reaction (HER) using Na₂S/Na₂SO₃ or glucose as sacrificial agents in aqueous solution was investigated. The ratio between CdS and MoS₂ plays an important role in the photocatalytic hydrogen generation. When the ratio between CdS and MoS₂ reaches 40 wt%, the photocatalyst showed a superior H₂ evolution rate of 55.0 mmol g⁻¹ h⁻¹ with glucose as sacrificial agent under visible light, which is 1.2 times higher than using Na₂S/Na₂SO₃ as sacrificial agent. Our experimental results demonstrate that MoS₂-based binary heterostructured composites are promising for photocorrosion inhibition and highly efficient H₂ generation.     

An insight to band-bending mechanism of polypyrrole sensitized B-rGO/ZnFe2O4 p-n heterostructure with dynamic charge transfer for photocatalytic applications

Developing a highly desirable multicomponent photocatalytic system for environmental remediation and water splitting is needed for current societal development. A visible active B-rGO/ZnFe₂O₄ photocatalyst was synthesized through the hydrothermal process, further magnify its electronic properties, the binary hybrid is modified with polypyrrole. The designed ternary hybrid utilizes the combining benefits of photo-sensitizer and interfacial charge transfer mechanism that ultimately boost its photocatalytic efficiency. The establishment of interfacial p-n heterojunction via band-bending mechanism between B-rGO (BG) nanosheets and ZnFe₂O₄ (ZnF) nanoparticles was validated from photo-density in the opposite direction and upturned V-shaped Mott-Schottky plots. It was observed that 2BG/ZnF@20PPY exhibits the best activity i.e., 100% reduction of 50 ppm Cr (VI) in 45 min and H₂-production of 598 μmolh^?1. Effective charge separation in 2BG/ZnF@20PPY is well supported by PL, TRPL, EIS, transient-photocurrent, and donor density calculations. The strong contact among the constituents in 2BG/ZnF@20PPY is well-correlated with XPS and Raman characterization.     

Graphene confined MoS2 particles for accelerated electrocatalytic hydrogen evolution

MoS₂ is a promising noble-metal-free electrocatalyst for the hydrogen evolution reaction. Extensive trials have been carried out to increase its low electrical conductivity and insufficient active sites. Here, a remarkable electrocatalyst for hydrogen evolution is developed based on the in-situ preparation of MoS₂ confined in graphene nanosheets. Graphene effectively controls the growth of MoS₂ and immensely increases the conductivity and structural stability of the composite materials. Remarkably, because of the plentiful active sites, sufficient electrical contact and transport, MoS₂ particles confined in graphene nanosheets exhibit an onset overpotential as small as 32 mV, an overpotential approaching 132 mV at 10 mA cm⁻², and a low Tafel slope of 45 mV dec⁻¹. This work presents a reasonable architecture for practical applications in efficient electrocatalytic H₂ generation.     

Synergetic effect of carbon self-doping and TiO2 deposition on boosting the visible-light photocatalytic hydrogen production efficiency of carbon nitride

To improve the visible light utilization and photogenerated carriers separation, carbon self-doped carbon nitride (C-CN) supported TiO₂ photocatalysts were synthesized via a designed two-step strategy. After carbon self-doping, the colloid TiO₂ were in-situ deposited on C-CN surface and crystalized by calcination. Simultaneously, the bulk C-CN structure was thermally exfoliated to nanosheet morphology. This strategy ensured the saturated deposition of colloid TiO₂ nanoparticles on C-CN nanosheets to form well-constructed heterostructure with sufficient interfacial contact. The as-prepared TiO₂/C-CN (TCN) heterojunction photocatalysts showed enhanced visible light absorption capability, resulting in impressively high hydrogen production efficiency as 212.7 μmol h⁻¹, which was 10.8 times higher than that of CN. The remarkably enhanced photocatalytic performance may be mainly ascribed to synergetic effect of carbon self-doping and TiO₂ deposition on the improved visible light utilization and photogenerated carriers separation. The probable mechanism in such well-constructed heterojunction photocatalysts was proposed based on the structural analysis, electrical and photoelectrical properties, and photocatalytic process. The proposed strategy may be extended to the preparation of diverse heterojunction photocatalysts with excellent performance for solar energy conversion.