Template-Made Ultrahigh, Broadband, and Omnidirectional Light Absorption Surface for Enhanced Solar Energy Harvesting and Utilization

Huiyong Li, Chen Shen, Xiongying Qiu, Siyuan Zhou, Mengxi Liu, Chun Li*, Hui Zhang*, Zhong Zhang*

Advanced Functional Materials (2024) doi:  https://doi.org/10.1002/adfm.202407135

ABSTRACT

The practical application of solar energy harvesting urgently calls for the facile preparation of high-performance ultrablack surfaces with broadband and omnidirectional light absorption performance; however, some roadblocks still need to meet these requirements simultaneously. Herein, cone-array ultrablack (CAUB) surfaces are prepared by combining feasible template replication and blade coating techniques. The elaborate micro-sized cone structure and high absorptive materials (polydimethylsiloxane@carbon black, PDMS@CB) offer the CAUB extremely high, broadband, and omnidirectional light absorption over the solar spectrum with an average absorbance of 99.35%. Under one sun irradiation, the CAUB can efficiently absorb solar energy, reaching a surface temperature as high as 75 °C. A solar-thermal-electric generator (STEG) made from the CAUB film demonstrates real-time solar-heat-electric conversion, achieving a high output power density of 330 µW cm−2. The CAUB film possesses excellent water repellency, flexibility, chemical solvent resistance, and potential for large-scale production, satisfying the application requirements of solar energy harvesting and utilization.