Nowadays, ammonia toxicity and organic pollutants raised significant health and environmental challenges that needs to be detection and removal. In this context, we have demonstrated that CuO synthesized by a cost‐effective co‐precipitation technique plays a dual functional role for photocatalysis and liquid ammonia sensing. Le‐Bail profile fitting of X‐ray diffraction pattern reveal pure monoclinic phase with C2/c space group and Fourier transform infrared (FTIR) spectrum confirms the characteristic stretching vibrational bond of Cu‐O at 423 cm −1 . UV‐visible spectrum estimates the band gap to be 2.68 eV. CuO demonstrates two distinct environmental applications, such as electrochemical sensing and photocatalytic degradation of detection of malachite green (MG) dye. We demonstrate liquid ammonia (40–1000 ppm) detection using CuO via Electrochemical Impedance Spectroscopy (EIS) with sensitivity of ∼122 Ω/ppm and limit of detection (LOD) of ∼6.8 ppm for the first time. Besides, CuO material also shows photocatalytic degradation of MG dye upto 81% in 120 min under visible light. The combined sensing of liquid ammonia and degradation of dye are attributed to the presence of oxygen vacancies along with the multiple valence state of Cu detected from X‐ray photoelectron spectroscopy.
Kumar et al. (Sun,) studied this question.