C IMLA MARY
Articles written in Bulletin of Materials Science
Volume 42 Issue 6 December 2019 Article ID 0256
Ligand-exchanged Cu$_2$ZnSnS$_4$ (CZTS) nanoparticles (NPs) were successfully synthesized from colloidal NPs by replacing the long chain organic ligand from the surface of NPs via a bi-phasic method. It was found that ammonium sulphide salt ((NH$_4$)$_2$S) plays a key role in changing the surface of the NPs from hydrophobic to hydrophilic. The efficacy of the ligand exchange process over the surface of the CZTS NPs was analysed using X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy and scanning electron microscopy with energy dispersive X-ray. The ligand-exchanged CZTS NP-based counter electrodes (CEs) were fabricated by drop casting the inorganic ligand (ammonium sulphide)-capped CZTS nanoink onto the conducting substrate. Our result indicates that dye-sensitized solar cells (DSSCs) with inexpensive CZTS NP-based CEs show 2.42% efficiency. The present result indicates that CZTS CEs will be helpful as an alternative CE to a Pt CE in DSSC application.
Volume 42 Issue 6 December 2019 Article ID 0270
Synthesis and characterization of less toxic copper indium zinc sulphide (CIS:ZnS)-alloyed quantum dots (QDs) were carried out and the ligand exchange process towards the efficiency enhancement in CIS:ZnS QD-sensitized solar cellwas demonstrated. The colloidal CIS:ZnS QDs were synthesized by an inexpensive heat up method with oleic acid as the capping ligand. The optical properties were analysed through ultraviolet–visible absorption and photoluminescence emission spectroscopy. The influence of the ligand exchange process on the CIS:ZnS QD-based solar cells was analysed with thefabrication of two batches of solar cells. The ligand exchange process was confirmed from Fourier transform infrared and thermogravimetric analyses. The QD-sensitized solar cells were fabricated using a CIS:ZnS QD-loaded titania photoanode and by employing copper sulphide as the counter electrode. The photovoltaic performance of the fabricated QD solar cells was analysed through photovoltaic characterization methods (current density–voltage characteristics of the devices under the simulated solar light conditions and external quantum efficiency measurements). The ligand-exchanged QD-loaded solar cells show enhanced power conversion efficiency compared to the long chain ligand-capped CIS:ZnS QD-sensitized solar cells.
Volume 42 | Issue 6
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