Promoting photocatalytic organic pollutant degradation of BiOIO3/ basic bismuth (III) nitrate by dual field effect: Built-in electric field and piezoelectric field effect

Piezoelectric material polarization field engineering has gotten a lot of interest in improving photocatalytic performance. In this study, an asymmetric piezoelectric semiconductor BiOIO 3 is combined with basic bismuth (III) nitrate (BBN) to form a two-dimension heterojunction, which endows the hybrid with a built-in electric effect and a piezoelectric potential in both light and ultrasonic states. Notably, BiOIO 3 /BBN 1:1/3 shows a remarkable photodegradation performance. Rhodamine B dye (10 mg/L, 50 mL) can be completely degraded within 3 min by 50 mg of BiOIO 3 /BBN 1:1/3, and piezoelectric photocatalysis has a higher kinetic constant (2.01 min −1 ) than single piezoelectricity or photocatalysis. Further experiments illustrate that such remarkable performance correlates heavily with both built-in electric field and piezoelectric field effects, which promote the separation and transformation of photogenerated carriers. Moreover, this hybrid can also effectively degrade Congo red, methyl orange, and methylene blue. The degradation pathway of RhB was deduced by HPLC-MS analysis and the mineralization efficiency of the reaction was tested. Our work may lay a unique foundation for the creation of extremely effective piezo-photocatalysts for wastewater purification, hydrogen production, and other piezo-optical processes, reflecting its potential for practical applications in protecting the environment. The principle and process of polarized photocatalytic removal of dyes in the presence of light and ultrasound. • BiOIO 3 /BBN 1:1/3 catalyst was obtained by a simple one-pot hydrothermal method. • Built-in electric field and piezoelectric field effects contribute to activity. • 50 mg BiOIO 3 /BBN 1:1/3 can completely degrade 50 mL of 10 mg/L RhB within 3 min. • BiOIO 3 /BBN 1:1/3 can degrade Congo red, methyl orange, and methylene blue.