Dawei's paper has been accepted for publication by Journal of Materials Chemistry A (IF 9.931). This paper is selected as the outside Front Cover of the journal, thanks to the high recognition and appraisal of the referees. Congratulations!

Dawei is a visiting scholar from School of Science, Xi'an Jiaotong University.

Title: Nickel Nanoparticles Individually Encapsulated in Densified Ceramic Shells for Thermally Stable Solar Energy Absorption

Authors: Dawei Ding, Kai Liu, Qikui Fan, Bitao Dong, Yang Zhang, Yadong Yin, Chuanbo Gao,* Shujiang Ding*

Link to the publisher: https://pubs.rsc.org/en/content/articlelanding/2018/ta/c8ta10690h

Abstract: While non-noble transition metal nanoparticles are widely explored in the field of solar energy harvesting and conversion at high temperatures, their high tendency to diffusion and oxidation may cause substantially reduced lifetime of the devices. To address this issue, herein, we demonstrate that Ni nanoparticles individually encapsulated in a densified ceramic shell, achieved by a SiO2 coating and a subsequent densification process, possess significantly enhanced stability at high temperatures. Ni diffusion is effectively prevented at temperatures as high as 800 °C, and the oxidation of the Ni nanoparticles is suppressed at 500 °C when exposed to air. A spectrally selective absorbing film fabricated with these densified Ni@SiO₂ NPs exhibits high optical absorption with reflectance < 20 % in the main solar irradiation region, superior to semiconductor Si-based solar absorber films. It also exhibits high thermal stability at 500 °C in air, at which temperature thermal degradation begins for most selective solar absorbers with high-melting-point metals and metal nitrides. The Ni@SiO₂ absorbing film developed in this work outperforms the state-of-the-art high-temperature solar absorbers, suggesting its applicability in high-temperature solar-thermal conversion systems.