Li Xiaojie, Li Xin, Zuo Pei, Chen Xiaozhe, Liang Misheng, Ma Le
Laser Micro Nanofabricat Lab, Beijing Institute of Technology, Beijing 100081, China.
Materials (Basel). 2021 Jul 8;14(14):3816. doi: 10.3390/ma14143816.
TiO is popular in photocatalytic degradation dye pollutants due to its abundance and its stability under photochemical conditions. Au loaded TiO can achieve efficient absorption of visible light and deal with the problem of low conversion efficiency for solar energy of TiO. This work presents a new strategy to prepare Au nanoparticles-loaded TiO composites through electric-field-assisted temporally-shaped femtosecond laser liquid-phase ablation of Au and amorphous TiO. By adjusting the laser pulse delay and electric field parameters, gold nanoparticles with different structures can be obtained, such as nanospheres, nanoclusters, and nanostars (AuNSs). AuNSs can promote the local crystallization of amorphous TiO in the preparation process and higher free electron density can also be excited to work together with the mixed crystalline phase, hindering the recombination between carriers and holes to achieve efficient photocatalytic degradation. The methylene blue can be effectively degraded by 86% within 30 min, and much higher than the 10% of Au nanoparticles loaded amorphous TiO. Moreover, the present study reveals the crystallization process and control methods for preparing nanoparticles by laser liquid ablation, providing a green and effective new method for the preparation of high-efficiency photocatalytic materials.
二氧化钛(TiO)因其储量丰富且在光化学条件下具有稳定性,在光催化降解染料污染物方面颇受青睐。负载金(Au)的TiO能够实现对可见光的高效吸收,并解决TiO太阳能转换效率低的问题。本文提出了一种新策略,通过电场辅助的时间整形飞秒激光液相烧蚀Au和非晶TiO来制备负载金纳米颗粒的TiO复合材料。通过调整激光脉冲延迟和电场参数,可以获得不同结构的金纳米颗粒,如纳米球、纳米团簇和纳米星(AuNSs)。AuNSs在制备过程中可促进非晶TiO的局部结晶,还能激发更高的自由电子密度与混合晶相协同作用,阻碍载流子与空穴之间的复合,从而实现高效光催化降解。亚甲基蓝在30分钟内可有效降解86%,远高于负载金纳米颗粒的非晶TiO的10%。此外,本研究揭示了激光液相烧蚀制备纳米颗粒的结晶过程及控制方法,为制备高效光催化材料提供了一种绿色有效的新方法。