Direct Laser Writing of Multimetal Bifunctional Catalysts for Overall Water Splitting
Direct Laser Writing of Multimetal Bifunctional Catalysts for Overall Water Splitting
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DOI：
10.1021/acsaem.2c03973
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发表时间：
2023-03
影响因子：
6.4
通讯作者：
Shannon McGee;Andres Fest;Cierra Chandler;N. Nova;Yu Lei;James M. Goff;S. Sinnott;I. Dabo;Mauricio Terrones;Lauren D. Zarzar
中科院分区：
文献类型：
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作者：
Shannon McGee;Andres Fest;Cierra Chandler;N. Nova;Yu Lei;James M. Goff;S. Sinnott;I. Dabo;Mauricio Terrones;Lauren D. Zarzar
水电解是一种可持续的方式，可以生产清洁的氢和氧燃料，并有助于缓解日益严重的气候变化问题，同时满足全球能源需求。需要高效、稳定和地球丰富的双功能催化剂来实现用于析氢反应（HER）和析氧反应（OER）的更有效的电化学电池。在这里，我们调查的合成，组成，性能和机制的多金属催化剂服务的双重功能，在OER和HER的水电解。通过激光合成方法，我们合成了嵌入在非晶氧化物基质中的纳米晶多金属合金口袋的非均相催化剂。我们评估了一系列混合过渡金属氧化物材料的OER和HER的性能和组成，最终合成了Cr0.01Fe0.27Co0.34Ni0.38Ox/Cy催化剂，其在碱性介质中在100 mA cm-2下具有1.76 V的稳定、高速率和有竞争力的整体水裂解性能。使用密度泛函理论获得洞察力的活性位点和机制，我们提出，包括少量的铬增加了能量状态的简并性，降低了成本形成的O 2 p-d键和H 1 s-d键由于从Cr的s，p和d轨道的杂化。用1.636 V的双电极水电解槽模拟燃料生产装置，我们发现催化剂在14-15 mA cm-2下稳定40 h。这种激光合成方法，允许方便和快速合成复杂的多金属系统演示如何掺杂Fe，Co和Ni异质非晶/纳米晶结构与少量的Cr是重要的双功能催化行为，特别是增加HER功能，在推进我们的理解，为未来的电催化设计。
Water electrolysis is of interest as a sustainable way to produce clean hydrogen and oxygen fuel and help mitigate the rising problems of climate change while meeting global energy demands. High-efficiency, stable, and earth-abundant bifunctional catalysts are needed to enable more effective electrochemical cells for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Here, we investigate the synthesis, composition, performance, and mechanism of multimetal catalysts serving dual functionality in both OER and HER of water electrolysis. Through a laser synthesis method, we synthesized heterogeneous catalysts of nanocrystalline multimetallic alloy pockets embedded within an amorphous oxide matrix. We evaluated the performance and composition of a range of mixed transition-metal oxide materials for both OER and HER, ultimately synthesizing a Cr0.01Fe0.27Co0.34Ni0.38Ox/Cycatalyst that has a stable, high-rate, and competitive overall water splitting performance of 1.76 V at 100 mA cm–2in an alkaline medium. Using density functional theory to gain insight as the active site and mechanism, we propose that the inclusion of a minor amount of Cr increases the degeneracy of energetic states that lowers the cost of forming the O 2 p–d bond and H 1 s–d bond due to the hybridization of s, p, and d orbitals from Cr. Using a two-electrode water electrolysis cell with a constant potential of 1.636 V to mimic the setup for fuel production, we found the catalyst to be stable at 14–15 mA cm–2for 40 h. This laser synthesis method allowing for facile and rapid synthesis of complex multimetal systems demonstrates how doping a Fe, Co, and Ni heterogeneous amorphous/nanocrystalline structure with small amounts of Cr is important for bifunctional catalytic behavior, particularly for increasing HER functionality in advancing our understanding for future electrocatalytic design.