基于选择性加氢反应的金原子簇催化剂设计

Selective hydrogenation of α, β-unsaturated aldehydes or ketones is an important topic for both fundamental research and applied research. However, it is very difficult for conventional methods such as deposition-precipitation and co-precipitation to prepare uniform gold clusters. Although colloid method can prepare uniform gold clusters, organic protecting reagents containing P, S, N are required. These protecting reagents will poison surface gold atoms of gold clusters, especially in gas-phase selective hydrogenation of α, β-unsaturated aldehydes or ketones. In this project, we will try to prepare size-controlled and uniform gold clusters by using polyvinyl alcohol ( PVA) as the protecting reagent. PVA can decompose easily under relative low temperature. We will also develop gas phase reduction method and plasma reduction method to reduce gold source on the surface of support and prepare uniform gold clusters. Then, we will investigate the interaction mechanism between gold clusters and supports and try to find suitable supports to stabilize gold clusters. Then, we will investigate the catalytic activities of gold cluster catalysts in H2-D2 exchange reaction and simple hydrogenation of alkene and alkyne, and identify the active sites for hydrogen dissociation. Finally, we will try our best to develop the high active gold cluster catalysts for selective hydrogenation of α, β-unsaturated aldehydes or ketones to α, β-unsaturated alcohols in liquid phase and in gas phase by carefully tuning the catalytic activities of gold cluster catalysts through optimizing gold cluster sizes, supports and support morphologies.

金原子簇催化α，β-不饱和醛（酮）选择性加氢具有重要的基础研究和应用研究价值。常规制备方法比如沉积-沉淀法和共沉淀法很难制备均匀金原子簇。胶体法能制备均匀金原子簇，但需要借助于含磷、硫、氮的保护剂。在α，β-不饱和醛（酮）气相选择性加氢反应中，这些保护剂将覆盖和毒化活性表面金原子。本项目将使用易热分解的聚乙烯醇作为保护剂合成尺寸可调、均匀的金原子簇。此外，还将发展气相还原法和等离子体法，在载体表面直接还原金源制备金原子簇。通过考察金原子簇和载体相互作用机制，制备出热稳定性优良的金原子簇催化剂。通过关联界面氧物种活性和金原子簇催化剂在H2-D2交换反应和简单烯烃、炔烃加氢反应中的活性，确认氢气解离活性中心归属。最终通过优化金原子簇（尺寸、形貌）、载体、载体形貌，调变金原子簇催化性能，开发出高性能金原子簇催化剂用于α，β-不饱和醛（酮）液相和气相选择性加氢制α，β-不饱和醇。

金原子簇催化α ，β -不饱和醛（酮）选择性加氢具有重要的基础研究和应用研究价值。常规制备方法比如沉降-沉积法和共沉淀法很难制备均匀金原子簇。胶体法能制.备均匀金原子簇，但需要借助于含磷、硫、氮的保护剂。在α ，β -不饱和醛（酮）气相选择性加氢中，这些保护剂将覆盖和毒化活性表面金原子。本项目采用易热分解的聚乙烯醇作为保护剂合成尺寸可调、均匀的金原子簇，并且将金原子簇负载于多种金属氧化物上，考察载体酸碱性、氧化还原性等对金催化剂催化活性的影响规律以及对金催化肉桂醛选择性加氢的影响；并基于实验数据对Au/ZnO、Au/In2O3催化肉桂醛选择性加氢制备肉桂醇提出了一个可能的反应机理。制备了复合氧化物载体并用于负载纳米金，通过调节复合氧化物载体组成来调变纳米金催化剂催化肉桂醛加氢的反应活性，并考察其循环使用性能。本项目通过优化金原子簇（尺寸、形貌）、载体、载体形貌，调变金原子簇催化性能，开发出高性能金原子簇催化剂用于α ，β -不饱和醛（酮）选择性加氢制α ，β -不饱和醇。