Facet-Dependent Cu2O Electrocatalysis for Wearable Enzyme-Free Smart Sensing

Exploiting electrocatalysis for wearable enzyme-free biosensors and biofuel cells has recently greatly developed in preliminary medical diagnosis and human healthcare fields. Herein, several facet-controlled cuprous oxide (Cu2O) nanostructures have been systematically fabricated to investigate the facet-dependent electrocatalysis mechanism. As a result, cuboctahedral Cu2O with a hollow structure exhibits optimal sensing performance for glucose detection compared with octahedral or extended hexapod Cu2O. The facet-dependent sensing process reveals that Cu2O­{100} and Cu2O­{111} facets are helpful in acquiring a higher interaction with enzyme-free substrates and accelerating electron transfer, respectively, to improve electrocatalytic activity. As a proof of concept, combined with a portable wireless device, wearable Cu2O enzyme-free biofuel cell systems can achieve glucose sensing by both open circuit potential and power output signals, which would potentially be used for a wearable enzyme-free energy platform. Therefore, this wearable enzyme-free smart sensing concept would help in the targeted establishment of biomarker electrocatalysts, and further offers considerable promise for the development of biofuel cells in the wearable healthcare monitoring field.