Aarhus Universitets segl

Electrocatalysis

Identifying sustainable, inexpensive catalysts for the Oxygen Reduction Reaction (ORR) and Hydrogen Evolution Reactions (HER) is critical for gaining widespread realization of green energy technology. With extensive knowledge on synthesis of nanocatalysts, such as High Entropy Nano Alloys (HENAs), the Brummerstedt Iversen group are exploring how these could be the electrocatalytic materials of the future.

Advanced Nanomaterials for Electrocatalysis

Metal and metal oxide nanoparticles have been under development by the Brummerstedt Iversen group for over a decade, where they are high-performance and cost-effective for a range of applications, including electrocatalysis (i.e. water splitting and CO2 reduction), NOx reduction, and photocatalysis. (See sections on Nanomaterials and In situ studies.) In our recent work aimed at optimization of their use as catalysts, synthesis and screening is performed in acidic and alkaline media, and examples of the materials under investigation are given below:

Metal NPs (e.g. Cu, Co, Ru, Ir, Pt-Ru, Ni, etc.)

Metal oxides (e.g. TiO2, MoO2, CoO, RuO2, IrO2, RuIrO2, etc.)

Structural strategies, including Ovacancy engineering, polymorphism, morphology engineering, etc. are being explored to further improve product selectivity (e.g. in CO2RR) and stability (e.g. in OER). In addition, the influence of supporting materials, e.g., TiO2, TiN, N-containing g-C, etc. on catalytic activity and stability are also being studied.

Optimization of HENAs for electrochemical reactions is another avenue which is being pursued in the Brummerstedt Iversen Group. This includes thorough structure investigation of ‘PtPdIrRuRh’ HENAs and the investigation of replacing noble metals with inexpensive alternatives (e.g. Cu, Co, Ni, etc.). A recent publication from the Brummerstedt Iversen group on HENAs demonstrated a remarkable general synthesis route to bimetallic and HENAs over a wide solubility range of solid solutions, which has previously been a bottleneck in the development and optimization of nanocatalysts.