Systematical investigation on the solar-thermal conversion performance of TiN plasmonic nanofluids for the direct absorption solar collectors

The research on the efficient utilization of solar energy has far-reaching significance. Meanwhile, the preparation of high-efficiency, low-cost nanofluids as the working fluid in the photothermal conversion system is the current research hotspot. Herein, TiN is introduced as a plasmonic nanoparticle with excellent optical absorption and photothermal conversion properties. In our work, the optical absorption properties of TiN nanoparticles (NPs) were compared with those of Au, Ag and Cu nanoparticles by FDTD method. The results showed that the TiN NPs could be used as a potential photothermal material because of its good optical properties and lower cost. In addition, TiN nanofluids (10-50 ppm) based on ethylene glycol were prepared by a two-step method, which were well dispersed. The optical properties and thermal conductivity of TiN nanofluids were also measured and discussed, because of its plasmon resonance effect, the absorption characteristics and thermal conductivity of TiN nanofluids have been greatly improved. The solar-thermal conversion experiments were carried out by simulated light source in a direct absorption solar collector (DASC), and the efficiency of TiN nanofluid was maximum increased by 67.1% compared with the based liquid glycol ethanol. These findings therefore suggested that TiN nanofluids have promise and potential in photothermal conversion applications.

Automated summary

TiN nanofluids, with excellent optical properties and thermal conductivity, show promise and potential in increasing solar energy utilization efficiency in photothermal conversion applications.