Hydrothermal Synthesis of ZnO Nanospheres Using Apple Pectin as Biotemplate and Application for UV Sensing

In this study, spherical-like ZnO UV photodetectors based on the facile hydrothermal method, induced different concentrations of apple pectin as the biotemplate. Apple pectin can react with zinc particles and change the pH value, which plays an essential role in modifying surface morphology. Moreover, apple pectin extracted from apple peels as carbon and nitrogen sources can also be used to improve absorption properties and increase depletion region to reduce dark current. The best results were obtained when 150 mg of apple pectin was used, showing a high UV-to-dark current ratio and fast response and recovery times. The UV-to-dark current ratio is as high as 80106.1, which is better than that of pure ZnO (4.47). Fast response and recovery times are also swift. The physical properties were evaluated using various techniques, including scanning electron microscopy, photoluminescence (PL), X-ray diffraction, and energy-dispersive X-ray (EDX), respectively. The results of this study suggest that the use of apple pectin in the hydrothermal synthesis of ZnO may offer a promising approach for modifying ZnO materials.