S-Scheme Co₉S₈ Nanoflower/Red Phosphorus Nanosheet Heterojunctions for Enhanced Photocatalytic H₂ Evolution

Abstract

Environmental and energy problems can be effectively alleviated by solar photocatalysis technology. In this work, an S-scheme Co 9 S 8 nanoflower/RP nanosheet heterojunction was fabricated using a solvothermal solvent evaporation strategy for effectively enhancing the photocatalytic H 2 evolution. The investigation shows that the introduction of spherical Co 9 S 8 can not only increase the electrochemical active surface area, provide more photoinduced charges, and decrease the electrochemical impedance of the composite system but also reduce the H 2 evolution overpotential, leading to a H 2 evolution rate of 1562.5 μmol•h −1 •g −1 over 1% Co 9 S 8 /RP sample, which is 8.2 and 18.9 times that of pure RP and Co 9 S 8 , respectively. In addition, the water contact angle of RP is obviously reduced from 11.8°to 3.1°a fter introducing Co 9 S 8 ; this superhydrophilic surface is conducive to the adsorption of water molecules on the catalyst surface.Further investigation shows that Co 9 S 8 and RP can form a built-in electric field, which can accelerate the migration of photoexcited carriers from the conduction band of RP to the valence band of Co 9 S 8 along the S-scheme path and reserve the highly active charges. This work provides an effective strategy to design a low-cost, extremely active, and stable RP-based S-scheme heterojunction for photocatalytic H 2 evolution.

Rational Photodeposition of Cobalt Phosphate on Flower-like ZnIn2S4 for Efficient Photocatalytic Hydrogen Evolution

“…The SEM image of Z5CP (Figure 1c) shows that Z5CP inherits the flower-like structure of ZIS. Notably, the flower-like structure can provide a number of active sites, and multiple layers of petals enable light to be reflected multiple times, which leads to enhanced light absorption [36,37]. In addition, the SEM image of Z5CP shows that the Co-Pi nanoparticles are highly dispersed, and no large Co-Pi particles were observed.…”

Ag-Doped ZnIn2S4 Nanosheets on Hollow Co9S8 Polyhedral Nanocages as Photocatalysts for Enhanced Hydrogen Production and Pollutant Reduction

“…A comparison of the hydrogen evolution rates between this work and previously reported similar systems under visible light is shown in Figure S3. The superior hydrogen evolution rate illustrates the great advantage of the hollow Co 9 S 8 /Ag:ZnIn 2 S 4 heterojunction over photocatalysts of similar types. − The photocatalytic hydrogen evolution reaction with an optimal ratio of the 1.0 wt % Co 9 S 8 /Ag:ZnIn 2 S 4 is evaluated through a long-term visible light cycle irradiation (Figure C). No significant deactivation was observed for 20 consecutive cycles, indicating the high stability of the prepared composite.…”

S-Scheme Heterojunctions Formed by MnSe2 Cubic Microparticles Supported on Red Phosphorus Nanosheets as Photocatalyst for H2 Production

“…Commercial RP was utilized as the phosphorus source, and micron-sized RP was prepared through a wet grinding method . Initially, 3 g of micrometer-sized RP was dissolved in 60 mL of deionized water.…”

“…Red phosphorus (RP) has garnered significant attention in the field of photocatalysis due to its advantageous properties, including low cost, a narrow band gap, and visible light responsiveness. , Despite possessing excellent physicochemical and semiconductor properties, pure RP faces challenges such as severe charge recombination and limited active sites on the surface involved in redox reactions, resulting in inefficient separation and migration of charge carriers and ultimately leading to unsatisfactory photocatalytic performance. , Several modifications have been employed to enhance the activity of RP, including elemental doping, morphological and structural modifications, the construction of heterojunction, and the loading of cocatalysts. , The activity of RP-based samples in this study and other literature was compared in Table S1 (Supporting Information). Among these strategies, the construction of an RP-based heterojunction is the most commonly employed approach to overcome the aforementioned limitations.…”

“…19,20 Several modifications have been employed to enhance the activity of RP, including elemental doping, morphological and structural modifications, the construction of heterojunction, and the loading of cocatalysts. 21,22 The activity of RP-based samples in this study and other literature was compared in Table S1 (Supporting Information). Among these strategies, the construction of an RP-based heterojunction is the most commonly employed approach to overcome the aforementioned limitations.…”