科研之友
微信
新浪微博
Facebook
分享链接
摘要
Crystalline Mg-Ti films with a thickness of more than 50 nm are only switched to a highly absorbing state and cannot be further changed to the transparent state after hydrogen loading at room temperature. To solve this problem, 200 nm thick amorphous MgTix (x = 0.11-0.29) films were prepared and their switchable mirror properties upon hydrogen loading and unloading were investigated. The results show that amorphous MgTix films can be reversibly switched between mirror and transparent states without an absorbing state due to the significant acceleration of hydrogen diffusion by amorphization. Moreover, the switching time of amorphous MgTix films are dramatically shortened with increasing Ti content. Using quartz crystal microbalance method plus transmission spectrum, it is experimentally proved that Ti addition shows little influence on hydrogen diffusion but a strong catalytic effect on MgH2 formation and decomposition. Therefore, the quick formation of a blocking MgH2 layer due to the combined effect of slower hydrogen diffusion in crystalline films and rapid MgH2 formation under Ti catalysis is considered as the reason why the crystalline Mg-Ti films cannot be changed to transparent state after hydrogen loading.
