Electrochemical conversion of CO2 to value-added products at copper/graphene composite catalysts

目前的项目建立在Sigma Energy Storage的HT-CAES技术的基础上，集成了一个二氧化碳处理模块，以提高效率和环境效益。通常，HT-CAES系统压缩环境空气作为能量存储介质，但在北极条件下，使用柴油机排气代替环境空气作为压缩空气能量存储的工作流体，导致从柴油机排气中捕获和液化高达58%的CO2。然后，液化的二氧化碳可以在注入电解槽之前储存起来，将其转化为有价值的燃料。该项目的目标是开发一种可持续的电化学过程，通过CO2还原反应（CO2 RR）将CO2转化为有价值的燃料，理想的是乙醇，可以在柴油发电机中重复使用，以进一步减少柴油消耗。为了评估SES的铜/石墨烯纳米颗粒对CO2转化的电催化性能，我们建议开发一种电化学电池，灵感来自膜电极组件（MEA）技术，再加上分析方法来检测和量化形成的产品的性质。为此，将对丹尼尔的盖伊实验室内先前用于CO2 RR研究的电化学电池进行修改，以插入MEA。通过探测MEA配置中的不同催化剂，将系统地评估反应参数和电化学性质。从CO2电解槽出来的气体产品将通过GC分析进行取样，而水溶液产品将通过NMR光谱进行分析。将仔细注意MEA的设计，以增加可用的电催化活性位点的数量。最后，将改变操作条件，以最大限度地形成所需的产品（乙醇，如SES所要求的）。电化学CO2转化技术的发展有可能为加拿大带来重大利益，在开发现场CO2增值产品和高效可再生能源系统方面，以减少柴油消耗和CO2排放。

The present project builds on Sigma Energy Storage's HT-CAES technology to integrate a CO2 processingmodule to provide increased efficacy and environmental benefits. Normally, the HT-CAES system compressesambient air as the energy storage medium, but under Arctic conditions, using diesel exhaust in place of ambientair as the working fluid for compressed air energy storage, leads to the capture and liquefaction up to 58% ofCO2 from diesel exhaust. The liquefied CO2 can then be stored before being injected into an electrolyser,converting it into valuable fuels. The goal of this project is to develop a sustainable electrochemical processthat will convert CO2 into valuable fuels via the CO2 Reduction Reaction (CO2RR), ideally ethanol which canbe reused in the diesel generators to further reduce diesel consumption.To assess the electrocatalytic properties of the SES' copper/graphene nanoparticles towards CO2 conversion,we propose to develop an electrochemical cell, inspired from the Membrane Electrode Assembly (MEA)technology, coupled with analytical methods to detect and quantify the nature of formed products. For thispurpose, an electrochemical cell already used for previous CO2RR studies inside Daniel's Guay Laboratory willbe modified for MEA insertion. Reaction parameters and electrochemical properties will be systematicallyevaluated by probing different catalysts in the MEA configuration. Gaseous products out of the CO2electrolyser will be sampled by GC analyses while aqueous products will be analysed by NMR spectroscopy.Careful attention will be devoted to the MEA design to enhance the number of available electrocatalyticallyactive sites. Finally, the operating conditions will be varied to maximize the formation of desired products(ethanol, as required by SES).The development of the electrochemical CO2 conversion technology has the potential for significant benefitsfor Canada in terms of development of on-site CO2 valorization to value-added products and highly efficientrenewable energy systems to reduce both diesel consumption and CO2 emissions.