Hu Jinrui, Wang Xuan, Zhou Yi, Liu Meihan, Wang Caikang, Li Meng, Liu Heng, Li Hao, Tang Yawen, Fu Gengtao
Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University Nanjing 210023 China
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University Sendai 980-8577 Japan.
Chem Sci. 2024 Dec 16;16(4):1837-1848. doi: 10.1039/d4sc07442d. eCollection 2025 Jan 22.
Hydrazine-assisted water splitting is a promising strategy for energy-efficient hydrogen production, yet challenges remain in developing effective catalysts that can concurrently catalyze both the hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR) in acidic media. Herein, we report an effective bifunctional catalyst consisting of Rh clusters anchored on CoO branched nanosheets (Rh-CoO BNSs) synthesized an innovative arginine-induced strategy. The Rh-CoO BNSs exhibit unique Rh-O-Co interfacial sites that facilitate charge redistribution between Rh clusters and the CoO substrate, thereby optimizing their valence electronic structures. When the current density reaches 10 mA cm, the Rh-CoO BNSs require working potentials of only 32 mV for the HER and 0.26 V for the HzOR, far surpassing commercial Pt/C. Furthermore, the Rh-CoO BNSs can work efficiently for hydrazine-assisted water electrolysis with a low voltage of 0.34 V at 10 mA cm and excellent stability. Theoretical calculations reveal that the optimized valence electronic structure within interfacial Rh-O-Co sites not only reduces the adsorption energy barrier of CoO for H* in the HER; but also optimizes the hydrazine adsorption in the HzOR and lowers the free energy change in the potential-determining step, where the facilitated dehydrogenation is observed in Raman spectra. This work provides a viable approach for designing efficient bifunctional catalysts for future hydrazine-assisted hydrogen production.
肼辅助水分解是一种颇具前景的高效制氢策略，但在开发能够在酸性介质中同时催化析氢反应（HER）和肼氧化反应（HzOR）的有效催化剂方面仍存在挑战。在此，我们报道了一种由锚定在CoO分支纳米片上的Rh簇组成的有效双功能催化剂（Rh-CoO BNSs），该催化剂通过一种创新的精氨酸诱导策略合成。Rh-CoO BNSs表现出独特的Rh-O-Co界面位点，有助于Rh簇与CoO底物之间的电荷重新分布，从而优化它们的价电子结构。当电流密度达到10 mA cm时，Rh-CoO BNSs在HER中仅需32 mV的工作电位，在HzOR中仅需0.26 V，远远超过商业Pt/C。此外，Rh-CoO BNSs在10 mA cm下以0.34 V的低电压进行肼辅助水电解时能够高效工作，且具有出色的稳定性。理论计算表明，界面Rh-O-Co位点内优化的价电子结构不仅降低了HER中CoO对H*的吸附能垒；还优化了HzOR中肼的吸附，并降低了电位决定步骤中的自由能变化，在拉曼光谱中观察到了促进脱氢现象。这项工作为设计用于未来肼辅助制氢的高效双功能催化剂提供了一种可行的方法。
