Ag/SiO_(2)/TiO_(2)纳米碗阵列的构建及其热电子传输

Research on Construction of Ag/SiO_(2)/TiO_(2) Nanobowl Arrays and Transport of Hot Electrons

为高效收集并利用Ag/TiO_(2)光阳极中的热电子,增大接触面积并改变热电子的传输方式是很有必要的。本文制备了大孔径且分层的Ag/SiO_(2)/TiO_(2)纳米碗阵列并利用COMSOL软件模拟了其局域电场分布和电子–空穴浓度变化。结果表明,更多的Ag粒子沉积到纳米碗内,添加的SiO_(2)层能促进光吸收并增强LSPR。大量热电子不再跨越肖特基势垒,而以隧穿形式穿过SiO_(2)层并注入TiO_(2)。Ag/SiO_(2)/TiO_(2)光电极的阻抗半径最小,光电流密度最高,表明电子迁移快速且受阻力小。

In order to improve the utilization of hot electrons in the Ag/TiO_(2)photoanode,there is a need to increase the contact area within Ag/TiO_(2)interface and transform the migration mode of hot electrons.In this work,hierarchical Ag/SiO_(2)/TiO_(2)nanobowl(NB)arrays with large pore size were fabricated and their local electric field distribution and variation of electron-hole concentration were simulated by COMSOL software.The results demonstrate that the nanobowl with curved surface contained more Ag particles,moreover,the addition of SiO_(2)layer gives assiatance to increase light absorption and enhance LSPR.A number of hot electrons can own the opportunity to inject into TiO_(2)in form of tunneling instead of surpassing the Schottky barrier.The impedance radius of the Ag/SiO_(2)/TiO_(2)is the smallest and the photocurrent density is the highest,indicating the rapid migration of electrons.