Microbial-induced Synthesis of nano NiFe LDH for High-efficiency Oxygen Evolution

NiFe layered double hydroxide (LDH) currently are the most efficient catalysts for the oxygen evolution reaction (OER) in alkaline environments. However, the development of high-performance low cost OER electrocatalysts using straightforward strategies remains a significant challenge. In this study, we describe an innovative microbial mineralization-based method for in situ-induced preparation of NiFe LDH nanosheets loaded on nickel foam and demonstrate that this material serves as an efficient oxygen evolution electrocatalyst. In the microbial mineralization process, bacteria adhere to electrode materials and promote the surface nucleation of nanomaterials when metal ions are present. Specifically, our findings indicate that biomineralization accelerates the formation and regulation of NiFe LDH. The new electrocatalyst displays excellent OER performance, with a small overpotential of 220 mV at 10 mA cm^-2 and a Tafel slope down to 38.6 mV dec^-1 in alkaline solution. The remarkable OER performance of the microbial mineralization-derived electrocatalyst is attributed to the synergistic effect of NiFe LDH and a bacterial-specific surface area that contains multiple active sites. This study has uncovered a new approach for the assembly of NiFe LDH that relies on biomineralization to bring about morphological and structural modification of LDH nanosheets.