High-Performance Oxygen Evolution Reaction Electrocatalysts Discovered via High-Throughput Aerogel Synthesis

A combinatorial high-throughput aerogel synthesis method is developed to systematically study the synergistic catalytic effects of multiple non-noble metal elements. A large number of aerogels with different compositions were synthesized and the corresponding ternary phase diagrams of the composition-electrocatalytic performance were constructed. A batch of aerogel catalysts with outstanding catalytic performance and stability for the electrochemical oxygen evolution reaction (OER) were discovered. Amorphous Fe3Co3Ni2-(oxy)hydroxide with excellent electrocatalytic performance (Tafel slope of 49 mV dec-1 and eta 100 of 421.48 +/- 6.41 mV) was found to achieve a mass activity of 611.23 A/gmetal at 1.63 V (vs RHE). X-ray photoemission spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) studies reveal that the incorporation of a third atom (Ni and Ce) into the binary aerogels enlarges the Co-O atomic distance and reduces the average valence state of Co, which in turn speed up the oxygen evolution reaction kinetics. This work puts forward a strategy for high-throughput synthesis and screening of electrocatalysts and provides valuable data sets for future machine learning and prediction of high-performance electrocatalysts. KEYWORDS: high-throughput synthesis, aerogel, oxygen evolution reaction, electrocatalysts, material genome

Automated summary

A combinatorial high-throughput aerogel synthesis method was developed to study the synergistic catalytic effects of multiple non-noble metal elements. Various aerogels with different compositions were synthesized and ternary phase diagrams of composition-electrocatalytic performance were constructed. Outstanding aerogel catalysts with excellent catalytic performance and stability for the oxygen evolution reaction (OER) were discovered.