Visible light-activated room temperature NH3 sensor base on CuPc-loaded ZnO nanorods

A one-step microwave-assisted hydrothermal synthetic approach was used to synthesize CuPc-loaded ZnO nanorods. Several characterization techniques were applied to analyze the compositional, structural and morphological information of the products, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV − vis spectrophotometer (UV-vis) and X-ray photoelectron spectroscopy (XPS). Both pure ZnO and CuPc-loaded ZnO were characterized in terms of their gas sensing performances towards various gases under light illumination. The results indicated that CuPc/ZnO sensor delivers excellent sensitivity and selectivity towards ammonia, accompanied with rapid response/recovery rate, remarkable humidity resistance and a low detection limit down to 0.8 ppm at room temperature under red light illumination. This work will open-up new vistas in the development of room temperature gas sensors based on wide-band gap semiconductors with visible-light irradiation.