Cu hollow microspheres synthesized by thermal decomposition and its photo-thermal conversion performance

Abstract

Cu hollow microspheres were synthesized by thermal decomposition of Cu(Ⅱ) formate-octylamine complexes in molten paraffin using oleyl amine (OA) as the surfactant. The synthesized products were investigated by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermal constant analyzer, UV-Vis-NIR and photo-thermal conversion test device. The relevant synthesis mechanism of Cu hollow microspheres was analyzed. The results show that Cu hollow microspheres can be obtained under the conditions of reaction temperature at 110℃, reaction time at 3h and amount of OA at 0.005mol, the average diameter and wall thickness of Cu hollow microspheres are about 380nm and 70nm, respectively. The formation mechanism of Cu hollow microspheres is that the primary Cu nanocrystals driven by minimizing the interface energy may aggregate around the gas-liquid interface between liquid paraffin and bubbles. The thermal conductivity and photo-thermal conversion performance of Cu hollow microspheres suspension are better than those of solid Cu.

Keywords

• Cu hollow microsphere
• thermal decomposition
• thermal conductivity
• photo-thermal conv-ersion performance