Multifunctional property exploration: Bi₄O₅I₂ with high visible light photocatalytic performance and a large...

Exploration of the versatility of materials is very important for increasing the utilization of materials. Herein, we successfully prepared Bi₄O₅I₂ powders via a facile solvothermal method. The Bi₄O₅I₂ photocatalyst exhibited significantly higher photocatalytic activity as compared to the common BiOI photocatalyst in the degradation of methyl orange, methylene blue and rhodamine B under visible light irradiation. Especially, for the degradation of methyl orange, the photocatalytic activity of Bi₄O₅I₂ is about 10 times that of BiOI. Moreover, Bi₄O₅I₂ exhibits an extremely high second harmonic generation response of about 20 × KDP (the benchmark) estimated by the unbiased ab initio calculations. The coexisting multifunction of Bi₄O₅I₂ is mainly because of the increased dipole moment due to the stereochemical activity of lone pairs that promotes separation and transfer of photogenerated carriers, then enhances the photocatalytic activity and results in a high second harmonic generation response. This indicates that Bi₄O₅I₂ may have good potential applications in photocatalytic and nonlinear optical fields.