Electric Field Assisted Femtosecond Laser Preparation of Au@TiO2 Composites with Controlled Morphology and Crystallinity for Photocatalytic Degradation

TiO2 is popular in photocatalytic degradation dye pollutants due to its abundance and its stability under photochemical conditions. Au loaded TiO2 can achieve efficient absorption of visible light and deal with the problem of low conversion efficiency for solar energy of TiO2. This work presents a new strategy to prepare Au nanoparticles-loaded TiO2 composites through electric−field−assisted temporally−shaped femtosecond laser liquid-phase ablation of Au3+ and amorphous TiO2. 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 TiO2 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 TiO2. 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.

Ultrafast and scalable laser liquid synthesis of tin oxide nanotubes and its application in lithium ion batteries

Laser-induced scalable and quick photo-chemical synthesis of tin oxide nanotubes has been illustrated and their application in lithium ion batteries has been investigated.

Research of the Liquid Level Detection System for Integral Stereolithography System

To improve the dimension accuracy of integral stereolithography (SL) system, the resin liquid level in SL system need controlled. Based on the measuring principle of laser triangulation, a laser liquid level detection system for SL system has been developed. The laser liquid level detection system consists of light source, Position Sensitive Detectors (PSD), PSD signal processing circuit and data acquisition system. According to the principle that electrical signal of PSD changes when resin liquid level vary, a PSD is employed to detect the liquid level height in the liquid level detection system. Confirmation experiment is conduct to test the accuracy of the detection system, and the experiment results indicated that deviation is 0.34% in the range of 6mm, and satisfy the accuracy requirement of integral SL system.