ENERGY CONVERSION

The hybrid catalysts that combine low-cost materials with a small amount of PGMs can provide the active and stable catalytic performance toward HER and OER by promoting the sluggish catalytic kinetics of PGMs. Our group focuses on developing hybrids catalysts that maximize the catalytic activity of PGMs by considering heterostructure interface between PGM and TM. Furthermore, we are interested in developing novel support materials for durable acidic OER.

Tailoring the structure of PGM-free catalysts is an effective strategy to enhance the catalytic activity. A self-supported structure can guarantee high stability due to the strong adhesion between the catalysts and substrates. Also, it can enlarge the ECSA and even facilitate charge transfer. Our group focuses on developing well-defined nano-architecture materials that are self-supported on the current collector can provide a solution to realize the high-performance HER and OER catalyst even at high current densities.

The use of seawater instead of fresh water for hydrogen production is highly advantageous because of its abundance in nature (∼97% of the water on Earth is seawater). In particular, hydrogen production from seawater electrolysis is much more effective in hot arid regions, where fresh water is scarcely available. Our group focuses on developing highly active and durable OER catalysts for selective OER in alkaline seawater electrolysis.

Ammonia is a promising sustainable carbon-free energy carrier of renewable electricity, benefitting from ease of liquefaction under moderate conditions and the high energy density of its liquid form. A lithium-mediated pathway has been isotopically confirmed to generate ammonia from N2 reduction, and shows promise in terms of high faradaic efficiency (FE), yield rate, and reliability. Our group focuses on developing novel cathode materials for promoting lithium nitridation in the lithium-mediated process.

The high dependency on Pt is one of the challenging issues in the  fuel cell technology. Despite its considerably high activity and selectivity, Pt/C is not optimal ORR catalyst because of their high costs and poor stability in acidic media. Our group focuses on developing Pt alloy nanomaterials that are cost-effective and highly active by regulating their unique electronic structure, in some cases even more active than pure Pt metal.