Tightened 1D/3D carbon heterostructure infiltrating phase change materials for solar–thermoelectric energy harvesting: Faster and better

Extensive use of thermal energy in daily life is ideal for reducing carbon emissions to achieve carbon neutrality; however, the effective collection of thermal energy is a major hurdle. Thermoelectric (TE) conversion technology based on the Seebeck effect and thermal energy storage technology based on phase change materials (PCMs) represent smart, feasible, and research‐worthy approaches to overcome this hurdle. However, the integration of multiple thermal energy sources freely existing in the environment for storage and output of thermal and electrical energy simultaneously still remains a huge challenge. Herein, three‐dimensional (3D) nanostructured metal–organic frameworks (MOFs) are in situ nucleated and grown onto carbon nanotubes (CNTs) via coordination bonding. After calcination, the prepared core–shell structural CNTs@MOFs are transformed into tightened 1D/3D carbon heterostructure loading Co nanoparticles for efficient solar–thermoelectric energy harvesting. Surprisingly, the corresponding composite PCMs show a record‐breaking solar–thermal conversion efficiency of 98.1% due to the tightened carbon heterostructure and the local surface plasmon resonance effect of Co nanoparticles. Moreover, our designed all‐in‐one composite PCMs are also capable of creating an electrical potential of 0.5 mV based on the Seebeck effect without a TE generator. This promising approach can store thermal and electrical energy simultaneously, providing a new direction in the design of advanced all‐in‐one multifunctional PCMs for thermal energy storage and utilization. All‐in‐one composite phase change materials (PCMs) with solar–thermoelectric conversion are fabricated by in situ nucleation of three‐dimensional nanostructured metal–organic frameworks onto carbon nanotubes via coordination bonding, followed by calcination and encapsulation of PCMs. The design strategy based on PCMs provides constructive guidance for engineering advanced multifunctional PCMs for thermal harvesting, solar–thermal, and thermoelectric applications.