Hydrophilic hyaluronic acid-induced crumpling of Nb2CTx nanosheets: Enabling fast humidity sensing based on primary battery

Combining advanced energy-generation technologies with sensors to develop self-powered sensing shows great potential in intelligent electronics, but sluggish response kinetics and low output are the main obstacles. Herein, we design a hyaluronic acid (HA)-induced crumpling of Nb2CTx nanosheet to construct hydrogen bond conduction network, and develop it for fast humidity sensing based on primary battery. The in-situ formation of organic/inorganic hybrid interphase with crumpling structure by electrostatic flocculation is capable to provide abundant adsorption sites and accelerate proton (H+) transport. Benefited from these, the Nb2CTx/HA primary battery-based humidity sensor (PBHS) not only exhibits an outstanding response and recovery speed (15.1 s and 3.4 s at 72.0 % relative humidity (RH)), high response (0.7 V), low hysteresis (3.6 % RH), but also can be also used as a nanogenerator with a power of 0.96 μW and sustainable voltage output for 12 h. Furthermore, the multifunctional applications are demonstrated in medical assisted monitoring, health care, intelligent sensing, and green-energy generation. This work offers a new insight into PBHS design and the development of high-performance power-generation humidity sensor.