The use of hydrogen can reduce CO emissions and alleviate energy shortages, but large-scale storage and transfer of hydrogen remain obstacles to utilization. Hydrogenation of CO to CHOH and dehydrogenation of CHOH to H and CO constitutes a “carbon neutral” cycle for hydrogen storage and release with CO and CHOH. Highly efficient heterogeneous catalysts are required for optimal hydrogen storage systems and improved cycling efficiency. Herein, the goal of this review is to provide a comprehensive discussion for well-defined heterogeneous catalysts, focusing on their distinct active site structures, electronic states, and the consequential impact of these characteristics on catalytic activities when employed with different carrier materials. The structure–activity relationships and reaction mechanisms of the catalysts are investigated with advanced characterization techniques. Moreover, some promising but incipient pathways, such as photothermal catalysis, are briefly discussed. It is expected that this review will inspire the design of highly efficient heterogeneous catalysts for promising CO-CHOH hydrogen storage systems with closed carbon cycles.

中文翻译：

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通过甲醇实现二氧化碳储氢：使用明确的多相催化剂进行高选择性和高效的催化

氢的使用可以减少二氧化碳排放，缓解能源短缺，但氢的大规模储存和转移仍然是利用的障碍。 CO加氢生成CH3OH以及CH3OH脱氢生成H和CO，构成了与CO和CH3OH一起储存和释放氢的“碳中性”循环。最佳的储氢系统和提高的循环效率需要高效的多相催化剂。在此，本综述的目的是对明确的多相催化剂进行全面的讨论，重点关注其独特的活性位点结构、电子态，以及这些特性与不同载体材料一起使用时对催化活性的影响。利用先进的表征技术研究了催化剂的结构-活性关系和反应机制。此外，还简要讨论了一些有前途但刚刚起步的途径，例如光热催化。预计本次综述将启发高效多相催化剂的设计，用于具有闭路碳循环的有前景的 CO-CHOH 储氢系统。