Spectroelectrochemical characterization of heterogeneous electrocatalyst surfaces

多相电催化剂表面的光谱电化学表征

• 批准号: RGPIN-2017-04184
• 负责人: Smith, Rodney
• 金额: $ 1.53万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=678512
• 关键词: Spectroelectrochemical; characterization; heterogeneous; electrocatalyst; surfaces

The electrocatalytic reduction of CO2 is a reaction that has captured the interest of generations of scientists and currently commands significant attention in industrial, government and academic circles. Much of the modern interest in electrochemical reduction of CO2 originates from the fact that, when coupled with water oxidation, this reaction provides a viable means to generate a sustainable, global carbon cycle. Such a cycle would act to mitigate the impact of anthropogenic CO2 emissions while providing a non-fossil fuel feedstock for synthesizing useful chemicals, ranging from hydrocarbon fuels to commodity chemicals. Despite decades of research, however, 2-electron reduction products with limited commercial/industrial interest remain the only products that can be reliably synthesized with acceptable selectivity. The proposed research program seeks to establish a long-term, strategic focus that will utilize state-of-the-art spectroelectrochemical techniques to perform mechanistic studies to enable the rational design of catalysts capable of selective conversion of CO2 into high value, commercially relevant chemicals. ******Numerous reports have described changes to the electrochemical reaction system that enable conversion of CO2 into mixtures of desirable hydrocarbon products. Strategies that have enabled hydrocarbon synthesis include electrode composition turning, electrode surface engineering, and addition of co-catalysts to the electrolyte solution. These approaches tend to produce a diverse mixture of chemical products, however, and the ability to selectively synthesize desirable products remains elusive. This research program will capitalize on recent advances in spectroscopic instrumentation and techniques to acquire structural information on heterogeneous electrocatalyst surfaces under operational conditions (i.e. in-situ spectroelectrochemistry). Spectroelectrochemical measurements performed during operation will enable changes in chemistry at/near the electrode surface to be monitored, yielding information regarding reaction mechanisms. Repetition of the experiments upon strategic, systematic variation of components in the overall system, upon addition of a series of co-catalysts for example, will reveal the impact of the reaction component on the reaction mechanism. The library of data that will be generated throughout this research program will be comparatively analyzed to reveal design principles enabling the rational design of electrocatalysts and reaction system modifications to improve the selectivity of electrocatalytic CO2 reduction.

CO2的电催化还原反应引起了几代科学家的兴趣，目前引起工业界、政府和学术界的高度关注。现代对二氧化碳电化学还原的兴趣很大程度上源于这样一个事实：当与水氧化相结合时，该反应提供了一种产生可持续的全球碳循环的可行方法。这样的循环将减轻人为二氧化碳排放的影响，同时提供非化石燃料原料来合成有用的化学品，从碳氢化合物燃料到商品化学品。然而，尽管经过数十年的研究，商业/工业兴趣有限的二电子还原产物仍然是唯一能够以可接受的选择性可靠合成的产物。拟议的研究计划旨在建立一个长期的战略重点，利用最先进的光谱电化学技术进行机理研究，以合理设计能够选择性地将二氧化碳转化为高价值、商业相关化学品的催化剂。 ******许多报告描述了电化学反应系统的变化，使二氧化碳能够转化为所需碳氢化合物产品的混合物。实现碳氢化合物合成的策略包括电极成分转变、电极表面工程以及向电解质溶液中添加助催化剂。然而，这些方法往往会产生多种化学产品混合物，并且选择性合成所需产品的能力仍然难以捉摸。该研究计划将利用光谱仪器和技术的最新进展来获取操作条件下异质电催化剂表面的结构信息（即原位光谱电化学）。在操作过程中进行的光谱电化学测量将能够监测电极表面/附近的化学变化，从而产生有关反应机制的信息。对整个系统中的组分进行战略性、系统性的变化（例如添加一系列助催化剂）后重复实验，将揭示反应组分对反应机理的影响。将对整个研究计划生成的数据库进行比较分析，以揭示设计原理，从而合理设计电催化剂和反应系统修改，以提高电催化二氧化碳还原的选择性。