半导体光催化还原CO2是当前研究热点之一，利用该技术生成甲醇、低碳烯烃（如乙烯、丙烯等）等重要基本化工原料，有望缓解温室效应并减少对进口化石资源的依赖。本项目拟针对低光催化效率、低选择性这两大问题，首次利用具有压电特性的有机无机杂化钙钛矿CH3NH3PbI3（MAPbI3）进行压电光催化CO2还原，研究MAPbI3极化产生的内建电场对压电光催化过程中的光生载流子复合和反应中间产物在催化剂表面吸脱附的影响，达到提高光催化效率和增加产物选择性的目的。建立超声功率、频率与催化效率、产物选择性之间的科学关系。利用固体核磁等表征手段探索MAPbI3压电光催化还原CO2的反应机制。该压电光催化技术普遍适用于具有压电特性半导体的光催化过程。模拟工业CO2排放环境，利用太阳能、风能等清洁能源还原CO2，为实际工业中催化还原CO2提供实验和理论依据。

Investigation into the CO2 reduction via capitalizing on semiconductors as photocatalysts has garnered much attention over the past decades. The use of semiconductor photocatalysts not only renders the alleviation of the greenhouse effect but also produces important basic chemicals, such as methanol and light olefins (e.g., ethylene, propylene, etc.), thereby mitigating the dependence of our country on imported fossil resources. In this context, a novel and robust strategy is, for the first time, proposed to enhance the photocatalytic efficiency and the product selectivity by utilizing the piezoelectric effect of organic-inorganic hybrid perovskite CH3NH3PbI3 (MAPbI3). It is notable that an internal polarized electric field built inside the piezoelectric semiconductor MAPbI3 will be exploited to mediate the recombination of photo-induced charge carriers and the adsorption/desorption of reaction intermediates on or from catalysts. The fundamental relationships between ultrasonic power/frequency and catalytic efficiency/product selectivity will be established. Solid state nuclear magnetic resonance (NMR) will be utilized to explore the mechanism of the piezoelectro-catalytic reduction of CO2. Such piezoelectro-catatlyic technique can be widely applied to the piezoelectro-photocatalysis of the piezoelectric semiconductors. In addition, solar light and wind will be employed as the irradiation sources to reduce CO2 in the simulated industrial CO2 emission environment. The proposed project is expected to lay both experimental and theoretical foundations on the large-scale implementation of piezoelectro-photocatalysis.