Collaborative Research: Electrochemical Reduction of CO2 to Small Organic Fuels on Encapsulated Metal Catalysts in Gas Diffusion Electrode Environment

PI：Li，文珍/威廉姆斯，Christopher Proposal编号：1235982/1235654机构：密歇根理工大学/南卡罗来纳大学哥伦比亚分校标题：合作研究：在气体扩散电极环境中，封装金属催化剂上的二氧化碳电化学还原为小型有机燃料大气中温室气体二氧化碳的增加已导致严重的全球变暖问题。将二氧化碳电还原为有机分子是一个关键目标，通过将二氧化碳回收到可用燃料中，将对全球碳平衡产生积极影响。然而，足够快并可以满负荷运行的电还原仍然是一个巨大的科学挑战。该合作团队基于其在催化、光谱和电化学工程方面的广泛研究专业知识，提议研究一类新型的碳纳米管(CNT)包裹的铜基纳米结构，用于在气体扩散相高效地电催化还原二氧化碳。研究假设是：1)通过优化碳纳米管的直径、长度和金属纳米粒子的分布，可以有效地调节碳纳米管通道内CO2和H物种的传输和电荷转移；2)碳纳米管通道的空间限制可以提高链增长的几率(形成C2燃料)；3)阳离子交换离聚体可以有效地调节反应部位接近中性的局部pH，以促进二氧化碳的还原。本项目将围绕三个方面的研究内容展开：1)合理设计、准确合成并充分表征碳纳米管包裹的具有合金或核壳结构的铜基双金属(Fe、Ag、Pd等)纳米粒子；2)利用原位电化学傅立叶变换红外光谱、气相色谱-质谱法和高效液相色谱研究碳纳米管包覆催化剂-阳离子交换膜离聚体界面上二氧化碳还原的机理步骤；3)将包覆催化剂组装成MEAs，并利用电化学方法、层析分析和微观动力学模型研究气体扩散电极环境下二氧化碳的还原。首先，对这些新型包覆催化体系的研究将促进对复合催化材料的精确合成和结构-催化功能关系的了解。其次，这些研究工作将加深我们对电力驱动将二氧化碳转化为可用的有机燃料(电子燃料)的理解。第三，它将促进基于固体聚合物电解质和气体扩散电极技术的二氧化碳转化知识，并支持全球范围内平衡全球碳循环和缓解全球气候变化问题的研究努力。参与其中的学生不仅将获得动手研究技能，还将学习分析、沟通、合作和创新技能。此外，督导计划会把所产生的成绩纳入现有的学士学位课程和企业项目。外展的努力会增加高中生吗？科学、工程和技术方面的兴趣，并最终通过可持续地提供这些领域的新一代研究人员来造福我们的社会。

PI: Li, Wenzhen / Williams, ChristopherProposal Number: 1235982 / 1235654Institution: Michigan Technological University / University of South Carolina at ColumbiaTitle: Collaborative Research: Electrochemical Reduction of CO2 to Small Organic Fuels on Encapsulated Metal Catalysts in Gas Diffusion Electrode EnvironmentThe increase of the greenhouse gas CO2 in the atmosphere has resulted in serious global warming issues. The electroreduction of CO2 to organic molecules is a critical goal that would positively impact the global carbon balance by recycling CO2 back into usable fuels. However, an electroreduction that is fast enough and can operate to full capacity remains a great scientific challenge. This collaborative team proposes to investigate a novel class of carbon nanotube (CNT) encapsulated Cu-based nanostructures for efficient electrocatalytic reduction of CO2 in gas diffusion phase, based on their extensive research expertise in catalysis, spectroscopy and electrochemical engineering. The research hypotheses are: 1) that inside CNT channels, CO2 and H species transport and charge transfer can be effectively tuned through optimizing the diameter and length of CNTs and distribution of metal nanoparticles; 2) that the spatial restriction of CNT channels can enhance chain growth probability (to form C2+ fuels); 3) that the cation exchange ionomer can effectively adjust the local pH of reaction sites close to neutral in order to facilitate CO2 reduction. The project will focus on three research tasks: 1) rationally design, accurately synthesize and fully characterize CNTs encapsulated Cu- based bimetallic (Fe, Ag, Pd, etc) nanoparticles having alloy or core-shell structure; 2) investigate mechanistic steps of CO2 reduction at the encapsulated catalyst-cation exchange membrane ionomer interface using in-situ electrochemical FTIR, gas chromatography-mass spectrometry and high performance liquid chromatography; 3) assemble encapsulated catalysts into MEAs and investigate CO2 reduction in gas diffusion electrode environment using electrochemical methods, chromatography analysis, and micro-kinetic modeling.This research will have several broad scientific and social impacts. First, studies of these novel encapsulated catalytic systems will advance knowledge of precise synthesis of composite catalytic materials and structure-catalytic function relationships. Second, the research efforts will deepen our understanding of electro-driven conversion of CO2 to usable organic fuels (electrofuels). Third, it will advance CO2 conversion knowledge based on solid polymer electrolyte and gas diffusion electrode techniques and support the world-wide research efforts to balance global carbon cycling and alleviate global climate change issues. The students involved will not only acquire hands-on research skills, but also learn analytical, communication, cooperation and innovation skills. In addition, the PIs will incorporate the generated results into the existing undergraduate courses and enterprise projects. The outreach efforts will increase high school students? interests in science, engineering and technology, and eventually benefit our society by a sustainably supply of new generation researchers in these fields.