Bi-MOFs with two different morphologies promoting degradation of organic dye under simultaneous photo-irradiation and ultrasound vibration treatment

For the first time, piezocatalysis activity has been observed in bismuth-based MOFs (ultrasound vibration treatment) with two different morphologies, namely FCAU-17 (flakes) and CAU-17 (rods). CAU-17 and FCAU-17 were synthesized by solvothermal and ultrasonic methods, respectively, with the same organic ligand (1,3,5-benzenetricarboxylic acid) and metal salt (Bi(NO3)3·5H2O). Among these, the apparent rate constant k of CAU-17 in piezo-photocatalysis is 3.9 × 10-2 min-1, which is ∼3.9 and ∼ 1.5 times of those in photocatalysis and piezocatalysis, respectively. CAU-17 showed much high piezo-photocatalytic activity during degradation of RhB. Efficiently coupling between piezocatalysis and photocatalysis has been realized in rod-like CAU-17 (ultrasound vibration treatment). Our results provide a new strategy to improve catalytic performance of Bi MOFs through an efficient synergistic piezo-photocatalysis approach for environmental remediation.