AP Seminar - Bio-inspired Nanoionic Materials for Energy & Information Related Device Applications

Inspired by nature, we have developed new nanoionic materials and devices which can mimic the functions of human brain and skin with low power consumption through engineering the ion migration in nanoionic devices. For example, a new design of an artificial perceptual system integrating ZnO‐based synaptic devices with Pt/carbon nanofibers‐based strain sensors for stimuli detection and information processing is presented. The device can emulate various essential functions, such as short‐term/long‐term plasticity, paired‐pulse facilitation, excitatory post‐synaptic current, and synaptic plasticity depending on the number, frequency, amplitude, and width of the applied pulses. Inspired by electric eels, harvesting energy from ubiquitous moisture is attracting growing interest in wearable electronics. However, several proposed mechanisms, such as the intrinsic gradient of polar functional groups principle and electrokinetic effect perspective, are in wide discrepancy. Here, through the combination of theoretical calculations involving time dimension on material's moisturizing process and experimental analyses, it is revealed the working principle through the water molecule triple roles in driving moisture electric generators (MEGs): 1) intrinsic H₂O absorption on the material surface and splitting into hydroxy group and proton due to the polarizability of the material surface determined by the static electric potential of the materials. This process induces the electrochemical potential difference of the materials via the work function changes; 2) freely diffused protons derived from the H₂O splitting work as the ions charge carriers; 3) via the hydrogen bond of the water molecules to drive charge carriers diffuse between opposite electrodes, maintaining the internal circuit current flow. This work may open a new era of advancement for a new energy conversion technology able to directly power wearable electronic devices.