Green Hydrogen Production

Green Hydrogen Production Through Water Electrolysis

Green hydrogen production is a pivotal solution in the transition towards sustainable energy systems due to its potential to store and deliver renewable energy in a versatile, clean form. Producing hydrogen through water electrolysis, where electricity from renewable energies splits water into hydrogen and oxygen, offers a zero-carbon emission pathway critical for decarbonizing various industrial sectors and transport systems. However, the widespread adoption of green hydrogen is currently hindered by two primary challenges: high production costs and the need for efficient electrocatalysts. The development of efficient electrocatalysts is crucial for enhancing the water electrolysis process. Current electrocatalysts often require rare, expensive materials and may not operate efficiently under the demanding conditions of high-volume hydrogen production. Research in this area focuses on innovating catalysts that are not only more efficient but also made from abundant and sustainable materials to improve the overall sustainability and feasibility of green hydrogen production.

Research Highlight-I

We collaborated with the perovskite solar cell team from ANU to set a new world efficiency record of 20% for the direct production of renewable hydrogen from solar energy using low-cost material. We designed a unique “flower-stem” structure of the NiMo catalyst, which provides a hierarchical architecture for uniform dispersion of highly active NiMo alloy nanograins. Such morphology can improve electrolyte–catalyst interaction through capillary forces and reduce the adhesion of gas-phase products, thereby enhancing the reaction kinetics. The flower-like nanosheets are closely connected to the surface of the Ni foam through the stem-shaped nanowires, providing significantly enhanced accessible surface area with good mass and electron transfer properties. This work has been reported as Hot News by RENEW ECONOMY (Sep. 2021) and PV MAGAZINE (Sep. 2021).

Y. Wang, A. Sharma, T. Duong, H. Arandiyan, TW. Zhao, D. Zhang, Z. Su, M. Garbrecht, F. Beck, S. Karuturi, C. Zhao, K. Catchpole, “Direct Solar Hydrogen Generation at 20% Efficiency Using Low-Cost Materials” Advanced Energy Materials, 2021, 2101053. DOI: https://doi.org/10.1002/aenm.202101053

Research Highlight-II

We showcased a systematic analysis of the key structural parameters controlling the oxygen evolution reaction (half-reaction of water splitting to produce hydrogen) of a representative family of NiFe-based metal-organic framework (NiFe-MOF). Unlike conventional MOF material with a large crystal size, I controlled the NiFe-MOF to be uniform ultrafine nanograins and grafted them homogeneously on the graphene nanosheet via a chemical integration strategy. The NiFe-MOF nanograins result in drastic increase in the accessible specific surface area and active electrochemical sites compared to the bulk MOF crystal structure, leading to dramatically enhanced catalytic activity. In addition to the material design strategy, this work also contributes to the fundamental understanding through in-depth structural and morphological characterizations and models of how the hierarchy of properties affects the oxygen evolution reaction with high intrinsic activity and plays a significant role in the charge transfer efficiency.

Y. Wang, BR. Liu, XJ. Shen, H. Arandiyan, TW. Zhao, YB. Li, M. Garbrecht, Z. Su, L. Han, A. Tricoli, C. Zhao, “Engineering the Activity and Stability of MOF‐Nanocomposites for Efficient Water Oxidation” Advanced Energy Materials, 11, 2021, 2003759. DOI: https://doi.org/10.1002/aenm.202003759