CAREER:Tailoring the nature of the active site of Ni electrocatalysts for electrochemical co-reduction of CO2 and H2O

职业生涯：设计坚固耐用的多相电催化剂，用于将二氧化碳和水转化为合成气。化石燃料的广泛使用以及随之而来的高水平二氧化碳排放是当代的主要挑战。解决这些挑战将需要开发方法来激活反向化学途径，在这些途径中，二氧化碳利用太阳能和/或风能等可再生能源将二氧化碳转化回高能分子(即一氧化碳和碳氢化合物燃料)。这些可再生能源最方便地被用作电力。许多被提议的处理化学过程中的二氧化碳的策略试图将二氧化碳转化回碳氢化合物。二氧化碳和水转化为合成气(CO+H2)就是这样一种过程，目前还没有有效的方法。合成气是一种制造化学品和燃料的方便原料。韦恩州立大学首席研究员Eranda Nikolla建议利用实验和理论技术相结合的方法，设计用于使用固体氧化物电化学系统(SOEC)将二氧化碳和H2O共还原为合成气的坚固耐用的电催化剂。SOEC是一种电化学系统，由于其在较高的操作温度下具有良好的反应动力学，因此可以促进CO2与H2O同时以非常高的速率共还原为合成气。这项拟议的研究将对该领域的发展产生广泛的影响，为设计高效地从二氧化碳和水中生成合成气的坚固的电催化剂提供一种新的基本方法，从而解决能源和气候变化方面的国家重大问题。此外，它还将成为一种工具，用于(I)从代表性不足的群体中教育西澳州立大学工程学本科生，(Ii)通过与当地高中、密歇根科学中心和NSF赞助的GoGirls计划的活动，促进K-12学生对STEM职业的兴趣，以及(Iii)通过研究和课程开发培训工程学研究生。虽然使用SOECs电化学共还原二氧化碳和H2O提供了很大的前景，但该领域还相当未被探索。这一过程的主要挑战之一是需要在高总电位下运行，这是由于与传统阴极电催化剂上的CO2和H2O的电化学还原相关的活化过电位损失(激活电化学过程所需的电位与可逆电位之间的差异)所致。为了应对这一挑战，PI建议将量子化学密度泛函理论(DFT)计算与实验电动力学研究相结合，以确定控制传统电催化表面上CO2和H2O共还原相关的过电位损失的电化学步骤。其目的是利用这一知识来设计改进的电催化剂，使共还原过程中控制步骤的过电位损失最小化，从而提高转化过程的能源效率。这项拟议的工作将为发现用于将二氧化碳和水转化为合成气的坚固而高效的电催化剂提供一种变革性的新方法。此外，它还将为PIS的长期目标奠定基础：(I)全面的研究计划，广泛旨在发现固态电化学系统中电化学转化的机理见解，并将这些知识转化为改进其性能的方法；以及(Ii)跨学科的教育和推广计划，目的是提高教学、培训和公众对能源和环境的认识。

CAREER: Design of Robust Heterogeneous Electrocatalysts for Conversion of CO2 and H2O to SyngasExtensive use of fossil fuels and consequential high levels of CO2 emissions are major contemporary challenges. Solutions to these challenges will require the development of ways to activate reverse chemical pathways in which CO2 is converted back into high energy molecules (i.e., CO and hydrocarbon fuels) using renewable energy sources, such as solar and/or wind energy. These renewable energy sources are most conveniently used as electricity. Many proposed strategies for dealing with CO2 from chemical processes attempt the conversion of CO2 back to hydrocarbons. The conversion of CO2 and H2O to syngas (CO+H2) is one such process for which no efficient approach currently exists. Syngas is a convenient feedstock for making chemicals and fuels. The Principal Investigator Eranda Nikolla at Wayne State University proposes to utilize a combination of experimental and theoretical techniques to design robust electrocatalysts for the co-reduction of CO2 with H2O to syngas using solid oxide electrochemical systems (SOECs). SOECs are electrochemical systems that can facilitate the simultaneous co-reduction of CO2 with H2O to syngas with very high rates, due to the favorable reaction kinetics at their high operating temperatures. The proposed research will have a broad impact in advancing the field by providing a new fundamental methodology for designing robust electrocatalysts for efficient generation of syngas from CO2 and H2O, thereby addressing nationally important issues in energy and climate change. In addition, it will become a tool for (i) educating undergraduate WSU engineering students from underrepresented groups, (ii) promoting STEM career interest in K-12 students, through activities with local high schools, the Michigan Science Center and the NSF-sponsored GoGirls program, and (iii) training of graduate engineering students though research and course development. While electrochemical co-reduction of CO2 and H2O using SOECs offers a great deal of promise, the field is fairly unexplored. One of the main challenges with this process is the need to operate at high overall potential, due to activation overpotential losses (the difference between the potential required to activate an electrochemical process and the reversible potential) associated with the electrochemical reduction of CO2 and H2O on conventional cathode electrocatalysts. In order to address this challenge, the PI proposes to combine quantum chemical density functional theory (DFT) calculations with experimental electro-kinetic studies to identify the electrochemical steps that govern the overpotential losses associated with co-reduction of CO2 and H2O on conventional electrocatalytic surfaces. The objective is to utilize this knowledge to design improved electrocatalysts that will minimize the overpotential losses of controlling steps in the co-reduction process, thereby increasing the energy efficiency of the conversion process. The proposed work will provide a transformative new methodology for the discovery of robust and efficient electrocatalysts for conversion of CO2 and H2O to syngas. Furthermore, it will build the foundation for the PIs long-term goals of developing (i) a versatile research program, broadly aimed at discovering mechanistic insights about electrochemical transformation in solid-state electrochemical systems and translating this knowledge to ways to improve their performance, and (ii) interdisciplinary educational and outreach programs with the aim of advancing teaching, training and public awareness regarding energy and environment.