Spin–orbit coupling and Lorentz force enhanced efficiency of TiO₂‐based dye sensitized solar cells

Abstract

We report on the effect of the strong spin -orbit coupling and the Lorentz force on the efficiency of TiO 2 based dye sensitized solar cells. Upon inclusion of Ho 2 O 3 , due to the strong spin -orbit coupling of the rare earth Ho 3+ ion, we do see 13% enhancement in the efficiency. We attribute such an enhancement in power conversion efficiency to the increased lifetime of the photoexcited excitons. Essentially, a Ho 3+ ion accelerates the phenomenon of the spin -rephasing or the intersystem crossing of the excitons in a photosensitizer. Increase in the absorbance and decrease in the photoluminescence intensity suggests a decrease in the recombination rate, hinting an enhanced charge transport and is in accordance with our electrochemical impedance spectra and the J -V characteristics. From the above we strongly believe that enhanced efficiency of the device is due to increased intersystem crossing which would accelerate the exciton dissociation. On top of spin -orbit interaction, a configuration where the electric and magnetic fields are perpendicular to each other helped in enhancing the efficiency by 16%, suggesting that the Lorentz force also plays a dominant role in controlling the charge transport of the photo-generated charge carriers. We strongly believe that this simple and novel strategy of improving the efficiency may pave the way for realizing higher efficiency dye sensitized solar cells.3

Metal Atom Effect on the Photophysical Properties of Mg(II), Zn(II), Cd(II), and Pd(II) Tetraphenylporphyrin Complexes Proposed as Possible Drugs in Photodynamic Therapy

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Resistive Switching Devices for Neuromorphic Computing: From Foundations to Chip Level Innovations

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A review on spectral converting nanomaterials as a photoanode layer in dye‐sensitized solar cells with implementation in energy storage devices

“…Recently in 2018, Kannan et al presented that in Ho 3+ ‐doped TiO 2 (HTO), the number of dissociated charges carriers increases because of intersystem crossing due to which current density was increased in HTO as compared to bare TiO 2 device. The strong spin‐orbit coupling of RE Ho 3+ ion increases the rate of excitonic dissociation from excited singlet electronic state to triplet excitonic state, which leads to enhancement in the charge dissociation process. Authors found that in the presence of a magnetic field, power conversion efficiency of HTO devices increased by 36.5% as compared to TO devices.…”