Electroreduction Of Carbon Dioxide To Ethanol With Cuprous Oxide Film By Electrodeposition

In recent decades,with the expansion of industrial scale,the greenhouse effect caused by excessive emission of carbon dioxide（CO₂）has worsened the climate around the world,and it is imperative to solve the problem of increasing CO₂ content in the atmosphere.In addition to energy-saving and emission-reduction measures at the root,the use of electrocatalytic methods to reduce CO₂ into valuable chemical products is a very promising approach.The CO₂ molecule is very stable,in order to make the electro-reduction CO₂reaction proceed smoothly,it is necessary to use a suitable catalyst.Copper（Cu）-based catalysts can effectively reduce CO₂ to high-value multi-carbon products such as ethanol.In addition to the problem of product selectivity,the catalyst for electro-reduction of CO₂ also has the problems of low catalytic activity and poor stability.For the problem of low catalytic activity,changing the structure and morphology of the catalyst surface to expose more active sites is the fundamental way to solve this problem.For the problem of poor stability,the ability of the catalyst to continuously and stably electrocatalytic reduction of CO₂ can be improved by protecting the active sites from being destroyed or degraded,maintaining a high exposure rate of the active sites,and enhancing the binding ability of the catalyst and the carrier.（1）This thesis used electrodeposition method to prepare self-supporting cuprous oxide（Cu₂O）film on foamed copper substrate as a catalyst for electro-reduction of CO₂.Due to the introduction of oxygen,Cu₂O can generate more active sites and improve catalytic activity.The self-supporting catalyst does not need to use an adhesive,which avoids the active sites being covered up and is firmly combined with the base material and is not easy to fall off.It has better stability.（2）The reaction conditions of electrodeposition and the addition of surfactant polyethylene glycol（PEG）were controlled to prepare（Cu₂O）films with different morphologies.Through a series of material characterization and electrochemical tests,the analysis results show that the catalyst has good catalytic performance for electroreduction of CO₂ which under the conditions of the electrodeposition solution p H is 10,the electrodeposition potential is-0.8 V（vs.Ag/Ag Cl）,the electrodeposition time is 20 min,the temperature is 55℃and addition of 6 g/L PEG 10000.The material,with an average film thickness of about 8.944μm,has a columnar cluster of regular polyhedral particles and a dense distribution of polyhedral particles in the surrounding area.It has good catalytic performance for electrocatalytic reduction of CO₂ to ethanol,and Faraday efficiency（FE）reaches 45.93%..