Mechanistic insight into the synergy between platinum cluster and indium particle dual cocatalysts for enhanced photocatalytic water splitting

• Published in: Journal of colloid and interface science 2024-09, Vol.670, p.774-784
• Main Authors: Zhang, Xinlei, Wu, Fei, Li, Guicun, Wang, Lei, Huang, Jianfeng, Song, Aili, Meng, Alan, Li, Zhenjiang
• Format: Article
• Language: English
• Subjects: adsorption; carbon nitride; Charge separation; Dual-metal cocatalyst; energy conversion; indium; nanoparticles; photocatalysis; photocatalysts; Photocatalytic hydrogen evolution; platinum; Polymeric carbon nitride; polymers; renewable energy sources; Synergistic effect
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2024.05.146

[Display omitted] •Dual-metal cocatalysts consisting of Pt NCs and In NPs were anchored on CN matrix.•The optimal Pt-In/CN exhibited an impressive photocatalytic H2 production activity.•Pt NCs and In NPs as traps boosted the separation and migration of photogenerated charges.•Bimetallic cocatalysts regulated optimal adsorption behavior of H* intermediates for fast kinetics. Photocatalytic H2 production is envisioned as a promising pillar of sustainable energy conversion system to address the energy crisis and environmental issues but still challenging. Herein, a strategy is proposed to design a dual-metal cocatalysts consisting of Pt nanoclusters (Pt NCs) and In nanoparticles (In NPs) anchored on polymeric carbon nitride (Pt-In/CN) for boosting photocatalytic water splitting. As expected, the designed Pt-In/CN photocatalyst exhibits an impressive H2 production rate of 6.49 mmol·h−1·g−1 with an apparent quantum yield (AQY) of 33.56 % at 400 nm, which is 2.8- and 11.2-fold higher than those of the Pt/CN and In/CN, respectively. Combining experimental characterization with theoretical calculation demonstrates the synergistic mechanisms underpinning the enhanced photocatalytic activity. The Pt NCs and In NPs serve as photogenerated electron and hole trapping sites, respectively, which achieves the spatial separation of charge carriers and induces the polarized surface charge distribution, thus fostering optimal adsorption behavior of intermediates. More importantly, the p-block In NPs modulate the electronic microenvironment of Pt NCs to attenuate the adsorption behavior of H* intermediates for accelerated H2 evolution kinetics. This work unveils a versatile strategy to regulate the electronic structures of dual-metal sites with synergy by establishing charge transfer mechanism for dual-metal cocatalysts.