Maize-stem-inspired multifunctional phase change composite integrating photothermal conversion and radiative cooling for 24-Hour continuous thermoelectric power generation

A maize-stem-inspired phase change composite was designed for all-day power generation applications. • Adaptively integrate solar photothermal conversion, latent heat storage, and radiative cooling within a single material. • Aligned GO/SiO 2 porous framework provides efficient heat pathways, stable paraffin encapsulation, and high mid-infrared emissivity. • Outdoor tests and simulations across 39 global cities demonstrate adaptive 24 h electricity generation from solar energy and cold space. Solar-thermal-electric conversion represents a promising pathway for off-grid power generation, yet its practical application is constrained by the low output density and intermittent nature of solar radiation. Herein, we design a maize-stem-inspired multifunctional phase change composite (PCC) that synergistically integrates latent heat storage and radiative cooling within a single material, enabling adaptive, uninterrupted electricity generation over 24 h. The composite is fabricated by encapsulating paraffin wax (PW) within a three-dimensional porous graphene oxide/silica (GO/SiO 2 ) framework, and exhibiting a latent heat of 130.2 J g −1 , a photothermal conversion efficiency of 90.7% and an energy storage capacity of 98.46%. When coupled with a thermoelectric module, the resulting system realizes continual 24 h electric energy generation by leveraging its combined photothermal conversion, energy storage, and radiative cooling functionalities. Under an irradiance of 500 mW cm −2 , the system delivers an output power density of 41.51 W m −2 . The innovative material design merges photothermal conversion, phase change energy storage, and passive radiative cooling within a single substance to adaptively capture energy from solar radiation and cold space. The study provides new insights into the efficient storage and utilization of solar energy, offering significant scientific value for developing uninterrupted solar-thermal-electric energy generation systems. Download: Download high-res image (349KB) Download: Download full-size image