Green Synthesis of Lamellae Rhombohedra Boron Suboxide for Efficient Photoreduction Catalysis with Visible Light Response

Abstract

Exploring novel photocatalysts is one of the primary missions for photocatalytic solar energy conversion. Metal‐free photocatalysts are of particular recent interest due to the drawbacks of conventional metal‐based photocatalysts, such as high cost, lack of abundance, and environmental hazardousness. A facile, environmental‐benign, and scalable synthetic strategy of well‐crystalline B6O particles is presented. The ultralow synthetic temperature of 90 °C and ambient pressure are the most mild synthetic conditions for this material. The prepared B6O shows a lamellae structure and regular rhombohedra morphology with a remarkably large surface area of 93.82 m2 g−1. It is proposed that the mild crystallization via a twin plane re‐entrant edge mechanism may contribute to the unique morphology. The rhombohedra B6O “R‐B6O” is explored to perform efficient photocatalytic water splitting and CO2 reduction without loading noble metal cocatalysts. The R‐B6O can also be used as a stable photocathode material for photoelectrochemical water reduction under visible light irradiation. The current work presents a new member to the family of metal‐free photocatalysts and photocathode materials.