3D/0D Cu₃SnS₄/CeO₂ Heterojunction Photocatalyst with Dual Redox Pairs Synergistically Promotes the Photocatalytic Reduction of CO₂

Abstract

As an inexpensive bimetallic sulfide with a narrow band gap, Cu3SnS4 has been widely used in solar-energy-driven catalytic reactions. However, the traditional tetragonal Cu3SnS4 has the inherent defect of fewer surface active sites and poor photogenerated carrier transport performance, which requires further modification to improve the CO2 photocatalytic reduction performance of tetragonal Cu3SnS4. In this work, the Cu3SnS4/CeO2 binary composites with dual redox pairs of Ce4+/Ce3+ and Cu2+/Cu+ were successfully designed and prepared via a simple solvothermal method as a bridge for the synthesis of composite materials. A series of characterizations, such as X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), photocurrent (PC), electrochemical impedance spectroscopy (EIS), etc., have confirmed that dual redox pairs and heterojunction synergistically improve the photochemical properties of hybrid Cu3SnS4/CeO2. Because of the unique three-dimensional/zero-dimensional (3D/0D) hierarchical structure of Cu3SnS4/CeO2, the splendid light absorption characteristic of Cu3SnS4 was retained, and the specific surface area of CC1 composite was improved. In addition, the water static contact angle experiments showed that the hydrophilicity of composites is inhibited. As a consequence, the fabricated CC1 composite with dual redox pairs acquires CO evolution that is 2.63 times greater than that observed for pristine Cu3SnS4. The innovative study will provide a feasible orientation for the field of solar energy-driven CO2 reduction reaction.

Review on CeO2-Based Photocatalysts for Photocatalytic Reduction of CO2: Progresses and Perspectives

“…85−87 Electrons and holes cannot be separated and transferred from photocatalyst A to catalyst B in Type III heterojunction photocatalysts because photocatalyst A's valence band (VB) and conduction band (CB) are higher than photocatalyst B's valence band and conduction band (Figure 6c). Wang et al 88 successfully designed and synthesized Cu 3 SnS 4 / CeO 2 binary composites with Ce 4+ /Ce 3+ and Cu 2+ /Cu + dual redox pairs by a simple solvothermal method (Figure 7a). It was shown that Cu 3 SnS 4 /CeO 2 's photochemical characteristics were greatly enhanced by the presence of double redox pairs and heterojunctions.…”

“…(a) Schematic diagram of CO 2 reduction mechanism on Cu 3 SnS 4 /CeO 2 composites. Reproduced with permission from ref . Copyright 2022, American Chemical Society.…”

“…Wang et al successfully designed and synthesized Cu 3 SnS 4 /CeO 2 binary composites with Ce 4+ /Ce 3+ and Cu 2+ /Cu + dual redox pairs by a simple solvothermal method (Figure a). It was shown that Cu 3 SnS 4 /CeO 2 ’s photochemical characteristics were greatly enhanced by the presence of double redox pairs and heterojunctions.…”

Emerging Single-Atom Catalysts and Nanomaterials for Photoelectrochemical Reduction of Carbon Dioxide to Value-Added Products: A Review of the Current State-of-the-Art and Future Perspectives

“…One alternative gaining a lot of focus worldwide is converting CO 2 into value-added products. There are numerous ways of transforming CO 2 to valuable products, viz., thermocatalysis, − biocatalysis, , radiolysis, , and photochemical (PC), − electrochemical (EC) − and photoelectrochemical (PEC) techniques. − The PC technique involves incorporating renewable solar energy for transforming CO 2 to produce valuable products. In contrast to the PEC process, it does not require any external potential bias and can be performed under ambient pressure and temperature conditions .…”

Portable self-powered photoelectrochemical immunosensor based on Cu3SnS4 nanoflower for ultra-sensitive and real-time detection of human cytochrome c

“…22,25 At present, the main photoactive materials are metal oxides, 26 metal chalcogenides, 27 MXenes, 28 covalent organic frameworks (COFs), 29 and metal–organic frameworks (MOFs). 30 Among the above mentioned nanomaterials, Cu 3 SnS 4 is a kind of metal chalcogenides with excellent photo-stability, 31 narrow bandgap (1.2–1.6 eV), high oxidation resistance/acid resistance, and high absorption coefficient, 32,33 making it a promising photosensitive material in the fields of photovoltaics, 34,35 photocatalysis, 36,37 thermoelectric, 38 electrocatalytic, 39 and pollutant degradation. 40 Thus, we believe that Cu 3 SnS 4 has the potential of fabricating PEC immunosensors with the advantages of fast response, high sensitivity, and specificity.…”