Piezocatalysis induced by polarization of piezoelectric materials is considered as an emerging technology in environmental cleanup. In this work, a piezoelectric material, Au nanoparticles modified BiVO₄ (Au/BiVO₄) is synthesized and its piezoelectric response is observed by piezo-response force microscopy. Au/BiVO₄ is used as a bifunctional piezocatalyst for simultaneous removal of 4-chlorophenol (4-CP) and hexavalent chromium (Cr(VI)) upon ultrasonic vibration, with 91% and 83% of removal efficiency in 120 min, respectively. The piezocatalytic performance of Au/BiVO₄ increases with the increase of ultrasonic power and the decrease of pH. The main active species for 4-CP oxidation and Cr(VI) reduction are determined to beOH and H₂O₂, respectively, since a significant formation rate ofOH is estimated by a probe method, and a high amount of H₂O₂ accumulation is directly detected. This study provides understanding on the piezocatalysis mechanism and brings new insights for development of piezocatalysis for multifunctional environmental applications.

压电材料极化引起的压电催化被认为是环境净化中的新兴技术。在这项工作中，合成了压电材料Au纳米粒子修饰的BiVO ₄（Au / BiVO ₄），并通过压电响应力显微镜观察了其压电响应。Au / BiVO ₄用作双功能压电催化剂，可在超声振动下同时去除4-氯苯酚（4-CP）和六价铬（Cr（VI）），在120分钟内的去除效率分别为91％和83％。随着超声功率的增加和pH值的降低，Au / BiVO ₄的压电催化性能增强。确定用于4-CP氧化和Cr（VI）还原的主要活性物质为OH和H ₂ O ₂分别由于通过探针法估计了显着的OH形成速率，并且直接检测到大量的H ₂ O ₂积累。这项研究提供了对压电催化机理的理解，并为开发用于多功能环境应用的压电催化带来了新的见解。