Green hydrogen production from water splitting powered by renewable electricity

通过由可再生能源或过剩电力供电的电解槽进行水分解是实现绿色氢可持续净零生产的完整解决方案，然而，这是一个能量上坡的过程，涉及阴极的析氢反应（HER）和阳极的析氧反应（OER）。虽然2电子HER相对容易，但4电子OER特别缓慢，并且在酸性条件下需要贵金属（Ir, Ru）电催化剂。然而，在碱性条件下，OER更容易实现，近年来取得了重大进展，非贵金属电催化剂如过渡金属（Ni, Fe）基层状双氢氧化物（LDHs）、磷化物和氮化物被有效地用于OER，后两者也被证明是HER和OER的双功能电催化剂。基于我们在OER阳极和HER阴极以及阴离子交换膜（AEM）的新型电催化剂和电极方面的初步工作，在这个项目中，我们将把最先进的电催化剂材料整合到碱性AEM上，开发基于膜电极组装的水电解器，以最大限度地提高资源和能源效率，实现可持续的氢气生产。我们将特别关注催化电极-电解质界面工程，以实现高效的反应动力学，以及在水电解槽中快速充电和质量传输，以减少过电位损失，获得最大的电压和整体系统效率。可交付成果：低成本、可扩展的绿色制氢水电解器演示器，具有优化的支架结构，避免使用贵金属，同时对所涉及的催化和电化学相互作用有深入的了解。

Water splitting via an electrolyser powered by renewable or excess electricity is a full solution for sustainable net-zero production of green hydrogen, however, it is an energetically uphill process involving the hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) at the anode. Whilst the 2-electron HER is relatively facile, the 4-electron OER is particularly sluggish and requires noble metal (Ir, Ru) electrocatalysts under acidic conditions. However, under alkaline conditions, OER is much facile and significant progress has been made recently where non-noble metal electrocatalysts such as transition metal (Ni, Fe) based layered double hydroxides (LDHs), phosphides and nitrides were effectively used for OER, and the latter two were also proven as bifunctional electrocatalysts for HER as well for OER.Build upon our nascent work on new electrocatalysts and electrodes for the OER anode and HER cathode, and the anion-exchange-membrane (AEM), in this project we will integrate the state-of-art electrocatalyst materials onto the alkaline AEM to develop membrane-electrode-assembly based water electrolyser, for sustainable hydrogen production with the maximum resource and energy efficiencies. We will pay particular attention to the catalytic electrode-electrolyte interface engineering to achieve efficient reaction kinetic, and fast charge and mass transports in the water electrolyser, to minimise overpotential loss and gain maximum voltage and overall system efficiency.Deliverables-A low-cost and scalable water electrolyser demonstrator for green hydrogen production, having an optimised scaffold structure and avoiding the use of noble metals, together with an in-depth understanding of the catalysis and electrochemical interactions involved.