Designing a Lower Band Gap Bulk Ferroelectric Material with a Sizable Polarization at Room Temperature

Das, S and Ghara, S and Mahadevan, P and Sundaresan, A and Gopalakrishnan, J and Sarma, DD (2018) Designing a Lower Band Gap Bulk Ferroelectric Material with a Sizable Polarization at Room Temperature. In: ACS Energy Letters, 3 (5). pp. 1176-1182.

PDF ACS_ene_let_3-5_1176-1182_2018.pdf - Published Version Restricted to Registered users only Download (1MB) | Request a copy

Abstract

A low band gap ferroelectric material with a sizable polarization at ambient conditions would constitute an ideal photovoltaic material to harvest solar energy because of its efficient polarization-driven charge carrier separation. We achieve this elusive goal by codoping a Jahn–Teller Mn3+ and Nb5+ pair for two Ti4+ ions in ferroelectric BaTiO3. Representing a charge-neutral dipole doping, this approach achieves for the first time a bulk ferroelectric oxide with the lowest band gap of 1.66 eV with a sizable polarization of nearly 70% of BaTiO3. We contrast this with the analogous system with Mn3+ replaced by the non-Jahn–Teller Fe3+ (3d5) ion, which even at a much lower level of doping reduces the polarization to 25% without reducing the band gap significantly, establishing the efficacy of the present strategy.

Item Type:	Journal Article
Publication:	ACS Energy Letters
Publisher:	American Chemical Society
Additional Information:	The copyright for this article belongs to the American Chemical Society.
Keywords:	Barium titanate; Energy gap; Ferroelectric materials; Ferroelectricity; Jahn-Teller effect; Solar energy; Solar power generation, Ambient conditions; Bulk ferroelectrics; Carrier separation; Co-doping; Dipole doping; Ferroelectric oxides; Ferroelectrics materials; Jahn-Teller; Low band gap; Photovoltaic materials, Polarization
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	11 Aug 2022 10:28
Last Modified:	11 Aug 2022 10:28
URI:	https://eprints.iisc.ac.in/id/eprint/75551

Actions (login required)

View Item