Optical sensors for in-situ real-time detection of ammonia

Abstract

The nitrate reduction reaction (NO3RR) is a highly promising method for ammonia production , which contributes to further advancing the production and application of ammonia as an industrial raw material and green energy. Currently, the evaluation of catalyst performance for electrocatalytic ammonia synthesis mainly relies on static indicators such as Faraday efficiency, ammonia yield per unit area, and overpotential. However, the dynamic in-situ description of ammonia generation on the electrode surface remains lacking. We propose an ammonia concentration sensor based on fluorescence excitation. Through in-situ real-time detection of the reaction, the changes in ammonia concentration at corresponding times in different regions on the electrode surface are calculated, thereby further improving the mechanism of the entire electroreduction reaction process. In this study, copper foam was used as the working electrode to verify the design of the sensor, which was then applied to the Co-based/Cu electrode synthesized.