Neutral Zn‐Air Battery Assembled with Single‐Atom Iridium Catalysts for Sensitive Self‐Powered Sensing System

Abstract

Abstract Self‐powered sensing systems (SPSSs) are critical components in smart portable electronic devices. Zinc‐air batteries (ZABs) as promising energy devices provide a great opportunity to develop novel SPSS for sensing applications owing to the merit of high open‐circuit potential. Herein, hierarchically porous single‐atom iridium embedded nitrogen‐doped carbon (SA‐Ir/NC) is reported as an efficient catalyst for the oxygen reduction reaction (ORR) in the neutral ZABs, enabling the SPSSs towards glucose detection with a high sensitivity and stable output signal. The resultant SA‐Ir/NC shows superior ORR activity and stability to commercial Pt/C in neutral electrolytes. According to the theoretical calculations, IrN 5 active sites in SA‐Ir/NC exhibit moderate adsorption free energy to reaction intermediates, giving SA‐Ir/NC excellent four‐electron ORR activity and well‐enhanced H 2 O 2 tolerance. When SA‐Ir/NC is applied as an air cathode, the as‐prepared ZABs display a large open‐circuit voltage of 1.42 V, a remarkable power density of 90.4 mW cm −2 , and excellent long‐term stability. After being integrated with glucose oxidase, the SPSSs are successfully established for sensitive detection of glucose based on a competitive model, holding great promise in biosensing applications.