Synthesis Of Cu-Based Nanomaterials And Their Catalytic Properties

The applications of Cu-based nanomaterials,which are based on the earth-abundant and inexpensive copper metal,have generated a great deal of interest in recent years,especially in the field of catalysis,like electrocatalysis,photocatalysis and thermocatalysis.The possible modification of the chemical and physical properties of these nanomaterials using different synthetic strategies to obtain novel Cu-based nanomaterials has been largely responsible for the rapid growth of interest in these nanomaterials and their applications in catalysis.Therefore,several types of Cu-based nanomaterials（metallic copper and alloys,copper oxides,hybrid copper nanostructures and copper nanoparticles immobilized into or supported on various support materials）have been successfully synthesized.Specifically,the inherent instability of Cu under atmospheric conditions put great challenge to the synthesis of stable metallic copper.This thesis is focusing on synthesizing different types of Cu-based nanomaterials,and testing their catalytic performance.The main results are showed as follows:The chapter one summarizes the types and synthetic strategies of different Cu-based nanomaterials.Then we describe their research progress in the field of catalysis.The chapter two:In this chapter,we learn from the new finding in our group that formate（HCOO）can reduce and stabilize metallic copper.Surprisingly,we provide a new stratege assisted by formate and organic amine,and then firstly obtain Cu ultrathin nanosheets.Through the time-tracking and control experiments,we finally provide possible growth mechanism for them.As effective CO₂ electroreduction catalysts,as-obtained Cu ultrathin nanosheets can reduce CO₂ to obtain CO with high selectivity.Furthermore,they can also act as fast and sensitive catalysts in the glucose sensor.The chapter three:Cu ultrathin nanosheets in chapter two were used as supporters.By using deposition method,we successfully prepared[Pd₂（μ-CO）₂Cl₄]₂-clusters（Pd₂）modified Cu nanosheets and then tested their performance in the semihydrogenation of phenylacetylene.The results demonstrated that our catalysts show high activity,selectivity and good stability.Basically,Pd₂/Cu catalysts are really simple model catalysts,which can help to understand the reaction process from the atomic and molecular level,and finally design more novel catalysts.The chapter four:Self-supported mesoporous CuCo₂O₄ nanorods and Co₃O₄ nanorods were synthesized by simple hydrothermal method.By comparing the catalytic performance of those two catalysts,we can find that the doping of Cu largely improves the activity and selectivity of CuCo₂O₄ nanorods to obtain methanol as the liquid product.Besides,the adsorption of intermediate CO may play a key role in obtaining methanol.The chapter five:Summarizing the research work of this paper and giving some prospects about challenges of preparing Cu-based nanomaterials and their potential catalytic applications.