Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.
Materials Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.
Chem Rev. 2020 Oct 28;120(20):11370-11419. doi: 10.1021/acs.chemrev.0c00158. Epub 2020 Sep 17.
Sustainable energy generation calls for a shift away from centralized, high-temperature, energy-intensive processes to decentralized, low-temperature conversions that can be powered by electricity produced from renewable sources. Electrocatalytic conversion of biomass-derived feedstocks would allow carbon recycling of distributed, energy-poor resources in the absence of sinks and sources of high-grade heat. Selective, efficient electrocatalysts that operate at low temperatures are needed for electrocatalytic hydrogenation (ECH) to upgrade the feedstocks. For effective generation of energy-dense chemicals and fuels, two design criteria must be met: (i) a high H:C ratio via ECH to allow for high-quality fuels and blends and (ii) a lower O:C ratio in the target molecules via electrochemical decarboxylation/deoxygenation to improve the stability of fuels and chemicals. The goal of this review is to determine whether the following questions have been sufficiently answered in the open literature, and if not, what additional information is required:(1)What organic functionalities are accessible for electrocatalytic hydrogenation under a set of reaction conditions? How do substitutions and functionalities impact the activity and selectivity of ECH?(2)What material properties cause an electrocatalyst to be active for ECH? Can general trends in ECH be formulated based on the type of electrocatalyst?(3)What are the impacts of reaction conditions (electrolyte concentration, pH, operating potential) and reactor types?
可持续能源的产生需要从集中式、高温、能源密集型工艺向分布式、低温转化转变，这些转化可以由可再生能源产生的电力驱动。生物质衍生原料的电催化转化将允许在没有碳汇和高热源的情况下，对分布式、能量贫乏的资源进行碳循环。需要选择性、高效的低温电催化剂来进行电催化氢化（ECH），以升级原料。为了有效地生成能量密集型化学品和燃料，必须满足两个设计标准：(i) 通过 ECH 实现高 H:C 比，以允许生产高质量的燃料和混合物，以及 (ii) 通过电化学脱羧/脱氧将目标分子中的 O:C 比降低，以提高燃料和化学品的稳定性。本综述的目的是确定在公开文献中是否已经充分回答了以下问题，如果没有，还需要哪些额外的信息：(1) 在一组反应条件下，可用于电催化氢化的有机官能团有哪些？取代基和官能团如何影响 ECH 的活性和选择性？(2) 是什么材料特性使电催化剂对 ECH 具有活性？能否根据电催化剂的类型制定 ECH 的一般趋势？(3) 反应条件（电解质浓度、pH 值、工作电位）和反应器类型有什么影响？
