多组元协同催化材料的结构控制及介尺度机制

The conversion of waste biomass into fuels, fine chemicals, and commodity materials has been paid much attention by governments and researchers for political, environmental, and sustainable concerns. Insufficient carbon-oxygen activation and undesired carbon-carbon cleavage, which causes the undesired reduction of selectivity, are always a major challenge. Efficient catalysts are therefore highly demanded for selective carbon-oxygen transformation. Here, a strategy to enhance the selectivity to catalytic carbon-oxygen transformation has been proposed. The strategy involves the design of required multi-scale structures and the methods to tailor the multi-scale structures of designed catalysts. The meso-science for structural control and tailor is to be focused on. The migration of cations and/or atoms and their evolution to clusters and particles are to be especially investigated.

项目针对生物质资源小分子转化利用中碳氧键重组选择性难以控制这一实际需求，提出模拟生物催化高效机理设计多组元金属催化材料的研究思路，通过控制多组元表面活性位的能量、几何结构和界面结构实现多组元高效协同催化；以多组元协同催化材料多尺度结构调控的介尺度机制为重点解决的关键科学问题，研究催化活性组元由原子向原子簇、微晶、纳晶等的迁移、演变，阐明多尺度过程的介尺度作用机制，多层次、多角度认识多组元表面结构控制的科学规律， “量体裁衣”地构建高效催化剂体系。

项目重点针对生物质资源小分子向高值化学品或能源化学品转化过程中碳氧键的定向活化和控制活化，采用层状前驱体拓扑转变策略，有效调控了多组元协同负载型金属催化剂的表面活性位及化学微环境等介尺度结构。利用层状双金属氢氧化物(LDHs)的拓扑转变，制备得到了Co-Ga和Co-Co活性位协同催化合成气转化制备乙醇及长链醇的负载型CoGa催化剂、纳米Ni与碱性载体协同催化纤维素重整制氢的层状双金属氧化物(LDO)负载Ni催化剂、表界面缺电子Ni与纳米Ni有效协同催化乙醇转化为系列四氢喹啉衍生物的Ni-LDO催化剂。项目还初步探索了LDHs前驱体拓扑转变-还原过程中，催化活性组元由原子向原子簇、微晶、纳晶等的演变行为：研究CoZnGaAl-LDHs在升温还原过程中向氧化物负载纳米CoGa的转变发现，控制升温速率可促使CoGa颗粒的形成受ZnO晶格诱导，在ZnO晶格诱导下形成暴露221晶面的CoGa颗粒；研究CuZnZrAl-LDHs向负载型纳米Cu颗粒的转变发现，控制升温速率可促使Cu-LDHs结构中两种不同局域环境的Cu中心(Cu-O-Cu和Cu-O-Mg(Al))梯度还原，从而得到纳米Cu栾晶。