Flame-assisted hydrolysis synthesis as a green combustion alternative for the preparation of metal oxide photocatalysts: Reactions and opportunities

Photocatalysis is one of the feasible and waste-free technologies to convert solar energy for effective use. The preparation of efficient photocatalysts by universal, sustainable and pollution-free methods is an issue of wide concern. On this basis, a green, efficient and sustainable method for preparing metal oxide-based photocatalysts-a one-step flame-assisted hydrolysis (flame thermal) approach is presented. During the process, the hydrolysis to metal oxides is induced and sustained by the combustion of alcohol solvent, which is spontaneously reactive and energy-saving. The combustion yields are used directly without any waste. Usually, metal oxides with microspherical morphology are produced. In this review, the reaction principles and applications of the method are mainly introduced. The keys to experimental success are discussed and perspectives for future work are given. Therefore, not only new thoughts for novel meth-odologies are originated, but intellectual challenges to understand and work on a general way to efficient catalysts are also provided. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

Photocatalysis is a feasible and waste-free technology for converting solar energy. This article presents a green, efficient and sustainable one-step flame-assisted hydrolysis approach for preparing metal oxide-based photocatalysts. The method uses the combustion of alcohol solvent to induce and sustain the hydrolysis process, resulting in metal oxides with microspherical morphology. The review discusses the reaction principles, applications, experimental success factors, and future prospects of this method, providing new ideas and intellectual challenges for efficient catalyst research.