Abstract
The surface properties and morphologies of titanium dioxide were modified by acid treatment. The titanium dioxide powders treated by various acids were examined by SEM, EDS, XRD, UV/Vis and zeta-potential meter, and were made to be electrode in solar device. The influence of acid treatment was studied in details. We find the zeta-potential of acid-treated titanium dioxide increases with increasing of acid concentration. On the other hand, the microstructure and grain size of titanium dioxides do not be changed after acid treated. Furthermore, according to EDS analysis, no extra elements in the titanium dioxide were observed. The photoelectron conversion efficiency of the solar devices markedly increases as the anodes were made by acid-treated titanium dioxides, owing to the reducing of the potential wall between grains and increasing of electron tunneling probability by increasing the surface charge of titanium dioxide. According to resistance measurement, the resistance of the electrode made by acid treated titanium dioxide is lower than that made by titanium dioxide without acid treatment.