Bismuth vacancies-enriched Bi4Ti3O12 nanosheets coated with UiO-66-NH2 for adsorption-combined piezocatalytic oxidation of HCHO

•Bismuth vacancies-enriched Bi4Ti3O12 coated with UiO-66-NH2 was fabricated.•Bismuth vacancies improved the piezocatalytic performance of BiTO.•The loading of amino-modified MOF enhanced the adsorption performance.•The formed heterojunction showed a high piezocatalytic oxidation rate of HCHO.•It is the first time to use pure piezocatalysis in HCHO removal.