Synergistic Trimetallic Nanocomposites as Visible–NIR–Sunlight-Driven Photocatalysts for Efficient Artificial Photosynthesis

Here, we report monodispersed tricomponent MnNSs–SnO2@Pt and MnNFs–SnO2@Pt nanocomposites prepared by simultaneous SnO2 and Pt nanodot coating on Mn nanospheres (MnNSs) and Mn nanoflowers (MnNFs) for highly efficient CO2 photoreduction in visible–NIR–sunlight irradiation. MnNFs–SnO2@Pt showed higher efficiency with a quantum yield of 3.21% and a chemical yield of 5.45% for CO2 conversion under visible light irradiation for HCOOH formation with 94% selectivity. Similarly, MnNFs–SnO2@Pt displayed significant photocatalytic efficiency in NIR and sunlight irradiation for HCOOH yield. MnNFs–SnO2@Pt nanocomposites also showed robust morphology and sustained structural stability with shelf-life for at least 1 year and were utilized for at least 10 reaction cycles without losing significant photocatalytic efficiency. The high surface area (94.98 m2/g), efficient electron–hole separation, and Pt-nanodot support in MnNFs-–SnO2@Pt contributed to a higher photocatalytic efficacy toward CO2 reduction.