Advances in triboelectric nanogenerators for self-powered wearable respiratory monitoring

Triboelectric nanogenerators (TENGs) have recently gained attention as a compelling platform technology for building wearable bioelectronics. Aside from being self-powered, TENGs are lightweight, low in cost, rich in material choice, comfortable to wear, and increasingly versatile with advances in sensitivity and efficiency. Due to these features, TENGs have become appealing in biomedical sensing applications, especially for human respiration monitoring. A wealth of information can be collected by breath-induced electrical signals, which are crucial in the analysis of a patient's respiratory condition and the early detection of harmful respiratory-linked diseases. TENGs have thus been used to continuously collect important respiratory data, from the breathing patterns, flow rate, and intensity of an individual's respiratory cycle to the chemicals that may be present in their breath. This review paper provides an overview of recent developments in TENG-based wearable respiratory monitoring as well as future opportunities and challenges for respiratory healthcare.