Shenghui Zhang#, Dingfang Hu, Hexi Wei, Binbin Zhai, Xiangquan Liu, Shuwen Tan, Zhouyu Chen, Yan Luo, Yinan He, Rong Miao*, Yu Fang*. ACS Appl. Energy Mater. 2025, DOI: 10.1021/acsaem.5c02719

Against the backdrop of continuously growing global energy demand and the increasing depletion of fossil fuels, the development of efficient and stable renewable energy technologies is of paramount importance. Solar-thermal-electric (STE) conversion technology, which transforms abundant solar energy into storable and utilizable electricity, represents a highly promising solution. However, a core challenge of this technology lies in the efficient and stable integration of photothermal materials with thermoelectric modules—conventional interface connection methods using adhesives or thermal pastes are prone to issues such as interfacial thermal resistance, low material utilization efficiency, and delamination during long-term operation, severely limiting the performance and practical application of STE devices.

To address this critical interface challenge, this study successfully developed a self-adhesive nanofilm synthesized at the humid air/dimethyl sulfoxide interface. With a thickness of only 55–60 nm, the film exhibits broad-spectrum absorption and rapid photothermal response characteristics. The imine groups in its molecular structure and its nanoscale thickness enable strong self-adhesion to various substrates, including thermoelectric modules, while withstanding extreme pH conditions, water rinsing, thermal shock, and organic solvent immersion, demonstrating exceptional environmental stability. Based on this, the research team constructed a novel STE device that achieved a high actual power output of 1.46 W m⁻² under 1-sun illumination, with no performance degradation after 90 cycles. A device built on this foundation, capable of floating on a lake and continuously generating electricity, successfully validated its practical application potential.

Through a sophisticated interfacial engineering strategy, this study has produced a nanofilm that combines efficient photothermal conversion, robust self-adhesion, and outstanding stability. This provides an innovative solution to the long-standing interface challenges in STE conversion and opens new pathways for the development of high-performance, long-lasting energy harvesting devices.

Figure 1. (a) Comparison of the absorption spectrum of the nanofilm with the solar spectrum. (b-d) Testing of the photothermal conversion ability of the nanofilm.

Figure 2. (a) Experimental setup for measuring STE conversion. (b–d) Equilibrium temperature, open-circuit voltage, and short-circuit current of different STE devices (e) Actual maximum output power density of different STE devices under different irradiations. (f–h) Stability testing of STE devices (i–j) Photograph of the STE platform. (k) Open-circuit voltage and short-circuit current of the STE platform as a function of outdoor solar intensity during different time periods of the day (March 25, 2025; 34.16°N, 108.95°E).

First Author: Zhang Shenghui, doctoral candidate, Shaanxi Normal University

Correspondence Authors: Prof. Fang Yu, Assoc. Prof. Miao Rong, Shaanxi Normal University

Full Text Link: https://pubs.acs.org/doi/10.1021/acsaem.5c02719