Well-Dispersed Small-Size Paraffin Encapsulated by Graphene Oxide via Pickering Emulsion for Personal Thermal Management.

Personal thermal management technology has emerged as a sustainable alternative to traditional climate control approaches. This study presents a novel method of uniformly dispersing and encapsulating small-sized paraffins inside a porous graphene oxide (GO) skeleton via a combination of Pickering emulsion and freeze-drying processes without involving multiple chemical reagents. The sheet wrapping effect and porous skeleton of GO can uniformly distribute the paraffin and efficiently prevent it from leaking at temperatures above its melting point. A small content of GO (7.4 wt %) inside GO/paraffin composite film can significantly leverage the thermal regulating property of the composite film, indicated by a reduced response window from 11 to 5 °C, 100% encapsulation efficiency, 6.5 times increased thermal conductivity from paraffin 0.2 W/(m·K) to 1.3 W/(m·K), and excellent phase change latent heat of approximately 160-180 J/g. The microstructure, thermal stability, thermal diffusivity, and leakage conditions of the composites are comprehensively studied by varying the GO content. The thermal regulation has been demonstrated by infrared thermal imaging at various background temperatures. This study offers a simple and straightforward method for preparing high-performance phase change composites for personal thermal management.