Ultrathin High‐Entropy Fe‐Based Spinel Oxide Nanosheets with Metalloid Band Structures for Efficient Nitrate Reduction toward Ammonia

Abstract Spinel oxides with tunable chemical compositions have emerged as versatile electrocatalysts, however their performance is greatly limited by small surface area and low electron conductivity. Here, ultrathin high‐entropy Fe‐based spinel oxides nanosheets are rationally designed (i.e., (Co 0.2 Ni 0.2 Zn 0.2 Mg 0.2 Cu 0.2 )Fe 2 O 4 ; denotes A 5 Fe 2 O 4 ) in thickness of ≈4.3 nm with large surface area and highly exposed active sites via a modified sol–gel method. Theoretic and experimental results confirm that the bandgap of A 5 Fe 2 O 4 nanosheets is significantly smaller than that of ordinary Fe‐based spinel oxides, realizing the transformation of binary spinel oxide from semiconductors to…

• NN
  National Natural Science Foundation of China

  Awards: 22379100, U21A20312
• DO
  Department of Education of Guangdong Province

  Award: 2023ZDZX3020