HfO2 nanodots incorporated in TiO2 and its hydrogenation for high performance dye sensitized solar cells. Issue 82 (18th August 2016)

• Record Type: Journal Article
• Authors: Laishram, Devika; Shejale, Kiran P.; Sharma, Rakesh K.; Gupta, Ritu
• Is Part Of: RSC advances. Volume 6:Issue 82(2016)
• Page Start: 78768
• Page End: 78773
• Publication Date: 2016-08-18
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra13776h
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : HfO2 nanodots are incorporated in TiO2 and hydrogenated together resulting in a photoelectrode material with a bandgap of 2.4 eV. The material exhibits interesting optical properties that are best suited for solar applications. Abstract : Black titania (H-TiO2 ) as a photoanode material has attracted huge attention due to its extremely high optical absorption in the visible region. Herein, black TiO2 doped with HfO2 shows ∼45.7% higher photo-conversion efficiency than H-TiO2 under identically similar conditions. The incorporation of HfO2 nanodots increased the optical scattering in H-TiO2 only when it underwent hydrogenation along with TiO2 . Hafnia-doped TiO2 (HfO2 /TiO2 ) is synthesized by a combination of simple sol–gel and hydrothermal method followed by thermal annealing under controlled hydrogen atmosphere. The hydrogenated H-(TiO2 /HfO2 ) exhibited very high optical absorption but slightly lower than H-TiO2 due to light scattering by HfO2 nanodots. We observed a sharp decrease in optical band gap of TiO2 /HfO2 from 3.2 to 2.4 eV up on hydrogen annealing, which is important in solar applications as demonstrated by the fabrication of high efficiency dye sensitized solar cells (DSSC).