Effect of Tm Doping on the Magnetic, Electronic and Optical Response Properties of <scp>TiO₂</scp> for Organic Solar Cell Application: A Density Functional Theory Study

ABSTRACT The magnetic field contribution to charge transfers of active layer materials for organic solar cells has been topical recently. The current study focuses on the effect of rare earth Tm doping on the charge transfer and magneto‐optical properties of TiO 2 . The Tm doping effect on TiO 2 shows a transition from ferromagnetic—antiferromagnetic—ferrimagnetic features. A steady band gap narrowing is observed with Tm doping of TiO 2 , which suggests increased localized defect buildup within the electronic structure of TiO 2 . The transition from electropositive to electronegative charge transfer features suggests Tm doping can act as a means of tuning the optoelectronic properties of TiO 2 . Additionally, the asymmetric spin‐up and down features of Tm 4f orbital states suggest it is an active agent in tuning the magneto‐optical properties of TiO 2 for improved organic solar cell harvesting.