Direct evidence of the dependence of surface state density on the size of SnO2 nanoparticles observed by scanning tunnelling spectroscopy

被引：25

作者：

Maffeïs, TGG

Owen, GT

Malagù, C

Martinelli, G

Kennedy, MK

Kruis, FE

Wilks, SP

机构：

[1] Univ Wales Swansea, Sch Engn, Multidisciplinary Nanotechnol Ctr, Swansea SA2 8PP, W Glam, Wales

[2] Univ Ferrara, Dept Phys, I-44100 Ferrara, Italy

[3] INFM, I-44100 Ferrara, Italy

[4] Univ Duisburg, D-47057 Duisburg, Germany

来源：

SURFACE SCIENCE | 2004年 / 550卷 / 1-3期

基金：

英国工程与自然科学研究理事会;

关键词：

tin oxides; computer simulations; polycrystalline surfaces; scanning tunneling microscopy; scanning tunneling; spectroscopies; surface electronic phenomena (work function; surface potential; surface states; etc.);

D O I：

10.1016/j.susc.2003.11.041

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

In this work, we report a scanning tunnelling spectroscopy (STS) study of 30 and 10 nm tin dioxide nanoparticles. The STS spectra give a surface band gap of 2.5 eV for both samples and show that the density of surface states in the band gap is around 6 times higher for the 30 nm particles than for the 10 nm particles. This provides direct experimental evidence for our theoretical model, which predicts a decrease in the surface state density as the particle size decreases, and partly accounts for the improved sensitivity of gas sensing devices fabricated with nanoparticles. (C) 2003 Published by Elsevier B.V.

引用

页码：21 / 25

页数：5

共 17 条

[1] In situ analysis of the conductance of SnO2 crystalline nanoparticles in the presence of oxidizing or reducing atmosphere by scanning tunneling microscopy [J].