Efficient Solar Thermal Energy Conversion and Utilization by a Film of Conductive Metal–Organic Framework Layered on Nanocellulose

Developing materials for efficient solar thermal energy conversion (STEC) is currently a promising field in energy research. Traditional STEC materials such as carbon and plasmonic nanomaterials have limited efficiency of solar heat utilization, despite their high photothermal conversion efficiency. This paper describes a film composed of hybrid nanofibers of a metal–organic framework layered on cellulose (MC film), resulting in both high photothermal conversion and heat utilization efficiency. The mechanically strong and flexible film can be designed as a solar-driven actuator, enabling large-angle actuation and high contractile power up to 2.5 times greater than that of human muscle. Furthermore, the gathered heat by a MC film-based apparatus can be manipulated to drive solar steam generation for highly efficient seawater desalination, generating clean water at rate of 2.25 kg m–2 h–1 under one-sun irradiation without surface salt accumulation. This work may provide a design rule for developing high-performance STEC systems.