One-Step Reactive Sputtering of Novel MoO_x Nanogradient Absorber for Flexible and Wearable Personal Passive Heating

摘要

Thermoregulating textiles as an emerging approach to promote people comfort have attracted significant attention in recent years. However, a simple, efficient, and cost-effective strategy that can autonomously absorb sunlight without extra power supply to warm the human body is lacking. Herein, a novel nanogradient MoO_x absorber (NMOA) on flexible polymers and wearable fabrics for personal passive heating is successfully fabricated via a simple one-step reactive sputtering technique. The surface steady-state temperatures of the NMOA coated on polymers and fabrics reach 78 and 90 ℃ under one sun illumination, confirming efficient solar thermal conversion, resulting from the superior absorption of NMOA. More importantly, the heating property of NMOA is on par with those of silver nanowire or carbon nanotube-coated textiles that use the Joule heating effect applied with a high voltage supply. It is noteworthy that achieving a high temperature at a low voltage is difficult, and hence the use of NMOA presents significant advantages. Due to the outstanding spectrally selective property of NMOA, the textile enables a 11 ℃ temperature enhancement in a cold environment (2 ℃). Together with its superior light-absorbing ability and excellent adhesion nature, the NMOA could be very promising in thermoregulating flexible and wearable applications.