MO/MAl2O4复合空心球的组装及光电转化还原CO2研究

以葡萄糖为模板剂，通过控制M、Al的比例，采用表面活性剂辅助一步水热法可控合成稳定性好、吸附性强的高活性复合MO/MAl2O4空心球。优化制备工艺条件，调控复合光催化剂的特征参数，获得可控制备空心球结构的普适方法。以光催化还原CO2评价其光催化性能，对样品通过原子掺杂、贵金属沉积、特种金属硫（氧）化物包覆等手段进行修饰改性，优选具有与CO2/CO2-的还原电位相匹配的纳米异质结空心球状复合光催化剂。结合现代表征技术，对其结构组成、能带结构、吸光性能等进行研究。探讨影响光催化还原CO2的各种因素，探明光催化剂与CO2间的相互作用机理以及异质结复合光催化剂中光生载流子的分离、复合及转移机制，提高光催化剂光电转换效率，实现CO2的高效还原。为CO2温室气体减排，实现碳氢化合物的再循环利用提供一定的理论与实验支持。

MO/MAl2O4 composite hollow microspheres with good stability, strong adsorptivity and high photocatalytic activities are fabricated via surfactant-assisted one-pot hydrothermal method by using glucose as template and adjusting the molar ratio of M to Al. A general method for synthesis of hollow microspheres structure can be obtained through optimization of the preparation technology and adjusting the characteristic parameters of composite photocatalysts. The photocatalytic activities of the as-prepared samples are evaluated by photoreduction of CO2 to hydrocarbon. The as-obtained photocatalysts can be modified by atomic doping, noble metal depositing and metal sulfide (oxide) loading to optimize the heterojunction hollow sphere-like nanocomposite photocatalysts matching the reduction potential of CO2/CO2-. Combined with the modern characterization techniques, the phase configuration, energy band structure and optical absorption property will be investigated. The effects of various factors on photoreduction efficiency of CO2 are discussed, and the reaction mechanism of the photoreduction of CO2, the interaction mechanism between the photocatalysts and CO2, the mechanism of photocarrier separation, composite and transfer in the heterojunction composite photocatalysts will be explored to improve photon-to-electron conversion and reduction of CO2 efficiency, which can provide theoretical and experimental support for reducing the emission of CO2, a greenhouse gas, and fulfilling the recycle utilization of hydrocarbons.