Structure-Dependent 4-Tert-Butyl Pyridine-Induced Band Bending at TiO2 Surfaces
2011 (English)In: International Journal of Photoenergy (Online), ISSN 1110-662X, E-ISSN 1687-529X, Vol. 2011, 401356- p.Article in journal (Refereed) Published
The role of 4-tert butyl pyridine (4TBP) adsorption on TiO2 surface band bending has been studied using photoelectron spectroscopy. Surface oxygen vacancies pin the Fermi level near the conduction band edge on rutile (110). 4TBP preferentially adsorbs in those vacancies and shift the Fermi level to lower binding energy in the band gap. This is done by transferring vacancy excess charge into the empty pi* orbital in the pyridine ring. The anatase (100) surface contains much less oxygen vacancies although the surface is much rougher than the rutile (110). 4TBP adsorption does not have any significant effect on the surface band bending. Thus the positive role associated with 4TBP addition to solar cell electrolytes is suggested to protection against adsorption of other electrolyte components such as Li and I.
Place, publisher, year, edition, pages
2011. Vol. 2011, 401356- p.
Chemical Sciences Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-133809DOI: 10.1155/2011/401356ISI: 000283223000001OAI: oai:DiVA.org:uu-133809DiVA: diva2:371611