Hydrovoltaic Effect Coupling with Capacitor Amplification: A Mode for Sensitive Self-Powered Electrochemical Sensing

Self-powered electrochemical sensors, which can functionwithoutexternal electricity, are incredibly valuable in the realm of sensing.However, most of the present testing methods are normally confinedto high environmental requirements, restricted lighting conditions,and temperature differences. Herein, an innovative self-powered electrochemicalsensor was successfully developed based on hydrovoltaic effect couplingwith capacitor amplification. Due to the combined merits from thetwo-dimensional transition metal carbides and nitrides (MXene)-polyaniline(PANI) with high surface potential and good hydrophilicity, and thecapacitor amplification strategy, the device could harvest electricenergy from water evaporation and displayed a high short circuit currentvalue. Under optimal conditions, the proposed self-powered electrochemicalsensor presented excellent sensitivity and high specificity for enrofloxacin(ENR) detection in the concentration range from 1 fM to 1 nM witha detection limit of 0.585 fM. Such a proposed sensor also has theadvantages of environmental friendliness and ease of use, which isan ideal choice for accurately and precisely detecting ENR in realsamples. The mode of such electrochemical detection outlined in thistechnical note implements a breakthrough in designing self-poweredelectrochemical sensors, providing a rational basis for developmentof a diversified sensing platform.