Enhanced Photovoltaic Performance of BiSCl Solar Cells Through Nanorod Array

Abstract

BiSCl single‐crystalline nanofibers were synthesized by a facile one‐pot solvothermal approach for the first time. BiSCl possesses a double chain type structure and grows readily along the c‐axis, resulting the fibrous morphology. UV/Vis absorption spectroscopy revealed that BiSCl nanofibers exhibit a strong light absorption in a wavelength range from UV to visible light, corresponding to a bandgap of 1.96 eV. Ultraviolet photoelectron spectroscopy and density functional theory calculations revealed that BiSCl is a direct n‐type semiconductor with valence band maximum and conduction band minimum located at 6.04 and 4.08 eV below the vacuum level, respectively. To investigate the photovoltaic performance, the homogeneous thin film of BiSCl‐nanorod array was fabricated on a TiO2 porous film by a modified solvothermal process, where the nanorod array is oriented vertically to the surface of the TiO2 porous film. A proper band alignment of BiSCl‐based solar cells with an architecture of fluorine‐doped tin oxide (FTO)/TiO2/BiSCl/(I3−/I−)/Pt gave a PCE of 1.36 % and a relatively large short‐circuit photocurrent density of 9.87 mA cm−2 for the first time. The preliminary photovoltaic study result revealed a potential possibility of BiSCl‐nanorod array as a light absorber for solar cells that can be fabricated by the low‐cost solution process.

Colloidal Bismuth Chalcohalide Nanocrystals

“…[51,52] These findings set the colloidal BiEX NCs as promising solar absorbers for photocatalytic and optoelectronic applications. [23,53,54] This work thus extends our knowledge on the chemistry of metal chalcohalide nanomaterials and contributes to establish this class of inorganic semiconductors as an effective complement to metal chalcogenides and halides for light-harvesting purposes.…”

Tailoring sizes and compositions of heavy pnictogen bismuth thiohalide nanorods and nanowires via heat-up method

“…[22][23][24] Many procedures have been reported for the synthesis of pnictogen chalcohalides such as growth from melts, 25 gas phase reaction, 26 and solvothermal methods. 17,27 These methods often require high temperatures, lengthy reaction times, or the use of toxic H 2 S gas for sulfurization. Therefore, a relatively low-temperature, robust, and facile synthesis method for metal chalcohalides is required.…”

( Bi 19 S 27 I 3 ) 0.6667 nanorods with more negative potentials of conduction band as highly active photocatalysts under visible light

“…Bismuth chalcohalides with excellent physical and unique chemical structures exhibited an easy-totune band structure and received extensive attention in photocatalytic applications in the last few years. [18][19][20][21] Wu et al 22 prepared single-crystalline Bi 19 Cl 3 S 27 nanorods by a simple solvothermal method and the photocatalytic results showed that the nanorods had high activity in the photocatalytic removal of Cr(VI). The Bi .333 (Bi 6 S 9 )Br semiconductor nanorods have been prepared by facile hydrothermal route.…”

“…Therefore, photocatalysts with negative E CB position were directly synthesized without any modification will be promising. Bismuth chalcohalides with excellent physical and unique chemical structures exhibited an easy‐to‐tune band structure and received extensive attention in photocatalytic applications in the last few years 18‐21 . Wu et al 22 prepared single‐crystalline Bi 19 Cl 3 S 27 nanorods by a simple solvothermal method and the photocatalytic results showed that the nanorods had high activity in the photocatalytic removal of Cr(VI).…”