MOF-regulated flexible wood carbon aerogel for pressure sensing

Abstract

Three-dimensional and lightweight carbon aerogels are promising for next-generation wearable devices. As the most abundant renewable resource on the planet, wood provides a green and sustainable raw material for the manufacture of lightweight and elastic carbon materials. Here, a simple and sustainable design is proposed to directly prepare elastic carbon aerogel with a layered structure from the wood. Zeolitic imidazolate framework (ZIF-L) was deposited on a wood aerogel matrix without lignin and hemicellulose by in situ growth. The presence of ZIF-L significantly reduced the volume shrinkage of aerogel during carbonization, and the carbonized ZIF-L improves the contact area and provides electron transport path. The prepared aerogel has a stress of 42 kPa under 80% strain, and the elastic strength and volume remain both above 98% after 200 times of compression, indicating that the aerogel has excellent compressibility and fatigue resistance. Based on this particular structural design, as-obtained aerogel shows excellent sensitivity as pressure sensors to detect subtle signals. In addition, the carbon aerogel can be directly assembled into a all-solid-state symmetric supercapacitor that show promising electrochemical performance and could be potential candidates for high-performance supercapacitors in wearable devices.