Construction of Cu7.2S4/g-C3N4 photocatalyst for efficient NIR photocatalysis of H2 production

• Published in: International journal of hydrogen energy 2023-07, Vol.48 (63), p.24285-24294
• Main Authors: Yu, Rui, Luo, Bifu, Chen, Min, Xu, Dongbo, Wu, Xiaojie, Li, Di, Huang, Yuanyong, Xie, Zhongkai, Shen, Nanjun, Meng, Suci, Shi, Weidong
• Format: Article
• Language: English
• Subjects: Cu7.2S4; g-C3N4; Hydrogen production; Near-infrared light responsive
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2023.03.167

Graphite-like carbon nitride (g-C3N4) has been regarded as a promising photocatalyst for solar-to-chemical conversion. Nevertheless, the narrow absorption of light extremely limited its photocatalytic performance under near-infrared (NIR) irradiation. Herein, the Cu7.2S4 with outstanding NIR absorption was successfully introduced to g-C3N4 nanosheets through a simple in-situ growth procedure. As expected, the constructed Cu7.2S4/g-C3N4 (CSCN) photocatalysts exhibit superior H2 production activity of 82 μmol g−1 h−1 under NIR light irradiation (λ > 800 nm), which outperforms currently reported g–C3N4–based NIR-driven H2 production systems. Especially, the optimal sample CSCN-5 displays a robust activity of 66 μmol g−1 h−1 at λ = 850 nm monochromatic light irradiation. The excellent photocatalytic performance is linked to the extended optical absorption as well as the efficient separation efficiency of photoinduced carriers, which are evidenced by the UV-visible absorption spectroscopy and photoelectrochemical test. This work provides an effective approach for constructing a Cu7.2S4/g-C3N4 photocatalytic system for the transformation of NIR solar energy into hydrogen. The novel NIR-driven Cu7.2S4/g-C3N4 composite photocatalyst was constructed through a convenient in situ growth process. As expected, the outstanding photocatalytic H2 yield was 82 μmol g−1 h−1 under the irradiation of NIR light (λ > 800 nm), which outperforms currently reported g–C3N4–based NIR-driven H2 production systems. More significantly, the sample CSCN-5 shows an optimum activity (66 μmol g−1 h−1) under λ = 850 nm monochromatic light irradiation. This work provides a feasible approach for achieving g–C3N4–based photocatalyst NIR-induced superior solar-to-chemical conversion. [Display omitted] •Cu7·2S4 modified g-C3N4 is prepared by a facile hydrothermal treatment method.•The Cu7·2S4/g-C3N4 composites show a superior optical adsorption from visible to NIR.•The Cu7·2S4/g–C3N4–5 composite exhibits excellent HER of 82 μmol g−1 h−1 (λ > 800 nm).•The HER of Cu7·2S4/g–C3N4–5 shows no obvious change after 4 runs within 20 h.