电镀黑铬太阳能选择性吸收器的热稳定性及耐蚀性(英文)

Thermal stability and corrosion resistance of electroplated black chromium solar selective absorber

黑铬作为最具吸引力的太阳能选择性吸收材料之一,已得到实验证实并用于太阳能收集器。本文评价了黑铬太阳能选择性吸收器的热稳定性和耐蚀性。采用三价铬镀液,在铜基体上电沉积了黑铬镀层。另外,采用六价铬镀液制备了六价铬黑铬镀层作为对比。根据ISO/CD12592.2标准,评价了热处理循环前后镀层的太阳能吸收/发射性能和热稳定性。分别采用扫描电镜和X射线衍射,表征了镀层的微观结构和化学组成。采用分光光度法测量了镀层的吸收率和发射率。结果表明,镀液中的配位剂对镀层的热稳定性有显著影响。与六价铬镀层相比,三价铬镀层具有更优异的热稳定性和耐蚀性。

Black chromium is one of the most attractive solar selective absorbers passed laboratory experiments and has practically been used in solar thermal collectors. The aim of this research is to evaluate the thermal stability and corrosion resistance of black chromium solar selective absorbers. Black chromium layers were electroplated on copper substrates from a bath containing trivalent and hexavalent chromium ions, respectively. Solar absorption and emission were measured by spectrophotometry before and after heat treatment cycles and the thermal stability of the deposited layers was evaluated according to ISO/CD 12592.2 standard. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） techniques were employed to characterize microstructure and chemical composition of the layers, respectively. It was found that complexing agent in the electroplating bath has a significant effect on thermal stability of the deposited absorber layers. It was also revealed that the trivalent chromium coating has superior thermal stability and corrosion resistance to the hexavalent chromium coating