Synthesis of hierarchical flower-like Bi2MoO6 microspheres as efficient photocatalyst for photoreduction of CO2 into solar fuels under visible light

Abstract

Hierarchical flower-like Bi₂MoO₆ microspheres were successfully synthesized via a facile hydrothermal approach, employing PVP as the crystal growth modifier. The building units of the hierarchical flower-like Bi₂MoO₆ were constructed by two-dimensional thin flakes, which intercrossed with each other and aggregated together to form the three-dimensional flower-like structure. The PVP amount and hydrothermal duration played crucial roles in the formation of the Bi₂MoO₆ architectures with evolving morphologies. The Bi₂MoO₆ samples were first evaluated for the photocatalytic reduction of CO₂ into methanol and ethanol as solar fuels under visible-light irradiation. It has been found that the hierarchical flower-like Bi₂MoO₆ exhibits highly efficient photocatalytic activity. After 4 hours of irradiation, the yields of methanol and ethanol were 24.8 and 18.8 μmol g_cat⁻¹ respectively, higher than those obtained over previously-reported Bi₂WO₆ hollow microspheres. This demonstrates that the hierarchical flower-like Bi₂MoO₆ is a simple, efficient and promising visible-light-driven photocatalyst for the photoreduction of CO₂ into solar fuels.