Band Gap Reduction in Ferroelectric BaTiO3 Through Heterovalent Cu-Te Co-Doping for Visible-Light Photocatalysis

Abstract

It is believed that ferroelectrics may serve as efficient photocatalysts as well as photovoltaic materials but for their large bandgaps which does not allow them to absorb a large part of the solar spectrum. We have explored theoretically within ab-initio density functional theory-based calculations, the efficacy of Cu and Te to co-dope BaTiO3 in reducing its bandgap while retaining its ferroelectric properties. Examining a dopant concentration of 11%, we find an insulating ground state being realized with a band gap reduction of 0.42 eV from the value for undoped BaTiO3 for some doping configurations. Ferroelectric distortions are found to survive even in the presence of doping suggesting possible applications in photocatalysis as well as photovoltaics.

Optical investigation and computational modelling of BaTiO3 for optoelectronic devices applications

“…Broad band-gap UV filters can be integrated into multifunction tandem cells as a front layer 14,15 .BaTiO 3 is considered one of the low-preparation cost alternatives for wide band-gap semiconductors [16][17][18][19][20][21] . Typically, the energy band gap of BaTiO 3 is varied from 3.2 to 3.4 eV [22][23][24][25] . Attempts were introduced in the literature to modulate the band gap, seeking visible absorption 23,24 .…”

“…Typically, the energy band gap of BaTiO 3 is varied from 3.2 to 3.4 eV [22][23][24][25] . Attempts were introduced in the literature to modulate the band gap, seeking visible absorption 23,24 . However, the wide band-gap BaTiO 3 is still very beneficial as a UV absorber 26,27 , especially in perovskite solar cells 28,29 , as reported in 20 .…”

Yttrium‐dopedSn3O4two‐dimensionalelectron transport material for perovskite solar cells with efficiency over 23%

“…Y doping narrows the band gap of Sn 3 O 4 from 3.69 to 3.61 eV. Metal element doping for SnO 2 or other metal oxides introduces new energy levels below the original conduction band bottom, resulting in a narrowing of the band gap 49–51 . Figure 3E is the E F cut off of Sn 3 O 4 and Y‐Sn 3 O 4 from UPS results.…”

Recent Progress of Amorphous Porous Organic Polymers as Heterogeneous Photocatalysts for Organic Synthesis

“…[15] However, pure inorganic catalysts often suffer from the disadvantages of low absorption efficiency and high cost. The strategies such as heterostructure building, [16,17] defect construction [18] and elemental doping [19,20] are required to adjust the bandgap and charge migration rate to suit practical needs. Nevertheless, inorganic catalysts' bandgap is difficult to adjust by diverse designs, which limits their photocatalytic performance.…”