A Simple Micro/Nano‐Porous Structure With Day‐Night Dynamic Thermal Control and High Thermal Conductivity for Enhanced Thermoelectric Power Generation

Abstract The main challenge of an all‐weather power generation system that combines radiative cooling and thermoelectricity is to dynamically regulate the temperature sources at both ends of the thermoelectric device. Previous studies have used stacked and flipped structures, thermochromic materials, and other methods. However, the above methods have complex structures, low thermal conductivity efficiency, and difficult‐to‐prepare materials. Therefore, in this paper, a porous structure of carbon nanomaterials with simple preparation, dynamically adjustable heat source during day and night, and high thermal conductivity in combination with thermoelectric devices with ultra‐high electrical efficiency is proposed. The structure has a solar spectrum absorption of 98.6%. Graphene film is used as a substrate material to enhance the longitudinal thermal conductivity. Experiments showed that the maximum voltage during day and night can reach 847 and 106 mV, the maximum temperature difference is 12.63 and 1.42 °C, and the maximum power density is 2112.96 mW m − 2 when combined with thermoelectric devices. Simulation models are used to analyze the environmental sensitivity of power generation units and to predict their power generation potential. This work provides superior photothermal/radiative cooling structures combined with thermoelectric elements for efficient all‐weather energy conversion and power output.