Publications by authors named "Yunchang Liang"

Magnetic-field enhancement of the oxygen evolution reaction (OER) represents a promising route toward more efficient alkaline water electrolyzers, yet its origin remains debated due to overlapping effects of mass transport and reaction kinetics. Here, we present a general experimental strategy that employs strong forced convection to suppress uncontrolled transport arising from natural diffusion and magnetohydrodynamic (MHD) flows. Using polycrystalline Au electrodes, we show that this approach resolves subtle OER variations under controlled flow and field conditions.

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Electrolytic hydrogen is identified as a crucial component in the desired decarbonisation of the chemical industry, utilizing renewable energy to split water into hydrogen and oxygen. Water electrolysis still requires important scientific advances to improve its performance and lower its costs. One of the bottlenecks in this direction is related to the sluggish anodic oxygen evolution reaction (OER).

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Efficient catalytic water splitting demands advanced catalysts to improve the slow kinetics of the oxygen evolution reaction (OER). Earth-abundant transition metal oxides show promising OER activity in alkaline media. However, most experimental information available is either from post-mortem studies or in situ space-averaged X-ray techniques in the micrometer range.

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Magnetic field effects on electrocatalysis have recently gained attention due to the substantial enhancement of the oxygen evolution reaction (OER) on ferromagnetic catalysts. When detecting an enhanced catalytic activity, the effect of magnetic fields on mass transport must be assessed. In this study, we employ a specifically designed magneto-electrochemical system and non-magnetic electrodes to quantify magnetic field effects.

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Controlling product selectivity is essential for improving the efficiency of multi-product reactions. Electrochemical water oxidation is a reaction of main importance in different applications, e.g.

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Capturing the surface-structural dynamics of metal electrocatalysts under certain electrochemical environments is intriguingly desired for understanding the behavior of various metal-based electrocatalysts. However, in situ monitoring of the evolution of a polycrystalline metal surface at the interface of electrode-electrolyte solutions at negative/positive potentials with high-resolution scanning tunneling microscopy (STM) is seldom. Here, we use electrochemical STM (EC-STM) for in situ monitoring of the surface evolution process of a silver electrode in both an aqueous sodium hydroxide solution and an ionic liquid of 1-methyl-1-octylpyrrolidinium bis(trifluoromethylsulfonyl) amide driven by negative potentials.

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In this work, alkaline hydrogen evolution reaction (HER) processes of three typical nickel-based electrocatalysts [i. e., Ni, α-Ni(OH) , and β-Ni(OH) ] were investigated to probe critical factors that determine the activity and durability.

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A sustainable future requires highly efficient energy conversion and storage processes, where electrocatalysis plays a crucial role. The activity of an electrocatalyst is governed by the binding energy towards the reaction intermediates, while the scaling relationships prevent the improvement of a catalytic system over its volcano-plot limits. To overcome these limitations, unconventional methods that are not fully determined by the surface binding energy can be helpful.

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Identification of catalytically active sites at solid/liquid interfaces under reaction conditions is an essential task to improve the catalyst design for sustainable energy devices. Electrochemical scanning tunneling microscopy (EC-STM) combines the control of the surface reactions with imaging on a nanoscale. When performing EC-STM under reaction conditions, the recorded analytical signal shows higher fluctuations (noise) at active sites compared to non-active sites (noise-EC-STM or n-EC-STM).

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The oxygen evolution reaction (OER) is a key process for renewable energy storage. However, developing non-noble metal OER electrocatalysts with high activity, long durability and scalability remains a major challenge. Herein, high OER activity and stability in alkaline solution were discovered for mixed nickel/cobalt hydroxide electrocatalysts, which were derived in one-step procedure from oriented surface-mounted metal-organic framework (SURMOF) thin films that had been directly grown layer-by-layer on macro- and microelectrode substrates.

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Identification of the most active surface sites is one of the key tasks in the development of new electrocatalytic materials. This is in many cases both time and resource consuming due to methodological difficulties of in situ detection of centers of this kind. In this work, we use the recently developed approach based on the analysis of the tunneling current noise recorded by electrochemical scanning tunneling microscopy (n-ECSTM) to compare the nature of the most active hydrogen evolution catalytic sites in a system consisting of sub-monolayers of platinum on a Au substrate to the one of palladium on Au.

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Development of efficient schemes of energy storage is crucial for finding a solution for the "generation versus consumption" problem. Aqueous Na-ion batteries have been already recognized as one of the promising candidates for large-scale energy-storage systems. Despite noticeable progress in this field, the actual intercalation mechanisms governing these battery cells are yet to be fully comprehended.

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A so-called solid electrolyte interface (SEI) in a lithium-ion battery largely determines the performance of the whole system. However, it is one of the least understood objects in these types of batteries. SEIs are formed during the initial charge-discharge cycles, prevent the organic electrolytes from further decomposition, and at the same time govern lithium intercalation into the graphite anodes.

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The activity of heterogeneous catalysts-which are involved in some 80 per cent of processes in the chemical and energy industries-is determined by the electronic structure of specific surface sites that offer optimal binding of reaction intermediates. Directly identifying and monitoring these sites during a reaction should therefore provide insight that might aid the targeted development of heterogeneous catalysts and electrocatalysts (those that participate in electrochemical reactions) for practical applications. The invention of the scanning tunnelling microscope (STM) and the electrochemical STM promised to deliver such imaging capabilities, and both have indeed contributed greatly to our atomistic understanding of heterogeneous catalysis.

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