Full-Self-Powered Humidity Sensor Based on Electrochemical Aluminum–Water Reaction

• DOI: 10.3390/s21103486
• Publication Date: 2021-05-17T16:19:57Z
• Authors: Marko V. Bošković; Biljana Šljukić; Dana Vasiljević R...; Katarina Radulović; Milena Rašljić Ra...; Miloš Frantlović; Milija Sarajlić
• Keywords: energy harvesting; 2. Zero hunger; Energy harvesting; Chemical technology; interdigitated capacitor; aluminum–air reaction; humidity sensing; TP1-1185; 02 engineering and technology; Aluminum–air reaction; Full-self-powered; 01 natural sciences; 7. Clean energy; Article; 0104 chemical sciences; Breath monitoring; breath monitoring; Humidity sensing; 11. Sustainability; full-self-powered; Interdigitated capacitor; 0210 nano-technology

A detailed examination of the principle of operation behind the functioning of the full-self-powered humidity sensor is presented. The sensor has been realized as a structure consisting of an interdigitated capacitor with aluminum thin-film digits. In this work, the details of its fabrication and activation are described in detail. The performed XRD, FTIR, SEM, AFM, and EIS analyses, as well as noise measurements, revealed that the dominant process of electricity generation is the electrochemical reaction between the sensor’s aluminum electrodes and the water from humid air in the presence of oxygen, which was the main goal of this work. The response of the sensor to human breath is also presented as a demonstration of its possible practical application.