A flexible self-powered humidity sensor with graphdiyne oxide

Abstract

Humidity sensors are widely used in various fields of research. However, continuous power supplementation remains a significant challenge for further development. Harvesting energy directly from the ubiquitous atmospheric moisture to provide a sustainable water source is a promising strategy for developing self-powered systems. In this study, we developed a self-powered humidity sensor based on a flexible fabric substrate modified with graphdiyne oxide with a significant oxidation gradient. The device produces a high voltage of approximately 0.55 V with a 7.0 µA current through spontaneous adsorption of water molecules from the ambient atmosphere. At 100% relative humidity, the device exhibited long-term and cyclic output stabilities. Compared to other carbon materials, the low conductivity of graphdiyne enables an extremely high gradient of oxidation through moisture-electric field annealing polarization. Additionally, the large water uptake of graphdiyne oxide enhanced the sensing performance of the self-powered humidity sensor. This study demonstrates the significant potential of graphdiyne oxide in self-powered sensing applications.