Photoactive bismuth silicate catalysts: Role of preparation method

The published papers highlight the photocatalytic properties of bismuth silicates, especially Bi2SiO5. Meanwhile, there is limited information on the formation of bismuth silicates that hinders the controlled synthesis of pure phases of bismuth silicates or composites on the basis thereof. The study is focused on the influence of preparation conditions on the interaction of initial reagents at each stage of synthesis taking into account the roles of solvent (water or ethylene glycol (EG)), precipitation agent, Si-containing component as well as the calcination procedure. The key role in these transformations is played by the stable Bi(III)-EG complex that participates in the Bi3+ reduction to metallic state under solvothermal conditions. The phase formation process is accomplished during the thermal treatment of the samples synthesized from EG solution. A four-phased composite material demonstrates the highest photocatalytic performance in photodegradation of Rhodamine B and phenol solutions via selective deethylation and mineralization processes, respectively.

Automated summary

The study identifies the key role played by the stable Bi(III)-EG complex in the reduction of Bi3+ to a metallic state during the synthesis of bismuth silicates. By considering factors such as solvent, precipitation agent, Si-containing component, and calcination procedure, bismuth silicate composite materials with high photocatalytic performance can be obtained.