Size influence on optical absorption property of ultra-fine nickel hollow spheres

Nickel hollow spheres (NHSs) with different diameter have been synthesized by autocatalytic reduction method. The morphology, particle size distribution and optical absorption property of NHSs were investigated by using FESEM, XRD, grain sige analytic instruments and so on. The results show that the optical absorption intensity increases obviously in ultraviolet-near infrared region with the decrease of particle size. While in infrared region, nickel hollow spheres almost have no absorption. After the heat preservation process, the grain size of samples become bigger and decrease the absorptance in UV-Vis-NIR region. For smaller particles, the absorption peak in ultraviolet range moves from 375 to 440 nm because of the increase of grain size.