Precise Preparation of CdS Thin Films for Efficient Sb₂S_3–ySe_y Thin-Film Solar Cells

Abstract

In this work, CdS thin films were prepared by chemical bath deposition (CBD) and Sb2S3–y Se y thin films were prepared by a hydrothermal method. Solar cells with the architecture of FTO/CdS/Sb2S3–y Se y /spiro-OMeTAD/Au were fabricated to evaluate the quality of CdS thin films as the electron transport layer. The precise preparation strategy with the combination of adjusting the thickness of CdS thin films prepared by CBD and changing the concentration of the CdCl2 methanol solution in the post-treatment process was first proposed. When the CdS thin-film thicknesses were 100, 80, 65, and 40 nm and the CdCl2 methanol solution concentration was 20 mg·mL–1, the power conversion efficiencies (PCEs) of the corresponding solar cells were 7.32% of 100 nm, 7.62% of 80 nm, 8.00% of 65 nm, and 7.55% of 40 nm. When the CdS thin-film thickness was 40 nm and the CdCl2 methanol solution concentrations decreased to 15, 13.3, 10, and 5 mg·mL–1, the PCEs were 7.98% of 15 mg·mL–1, 8.46% of 13.3 mg·mL–1, 7.71% of 10 mg·mL–1, and 7.31% of 5 mg·mL–1. Therefore, the 40 nm thick compact and full-coverage CdS thin film without the appearance of residual CdCl2 can be successfully obtained using the precise preparation strategy and achieved an optimal PCE of 8.46%. The precise preparation strategy is also valuable to develop the ultrathin, compact, and full-coverage CdS thin film as the electron transport layer for CdTe thin-film solar cells.

Efficient Sb2S3 and Low Se Content Sb2SeyS3–y Indoor Photovoltaics

“…According to our previous report, the CdS layers were deposited on FTO and FTO/SnO 2 substrates by CBD. The chemical composition of the growth solution was 1.5 mM Cd(NO 3 ) 2 , 48 mM CS(NH 2 ) 2 , and 1.69 M ammonia.…”

“…The preparation of the spiro -OMeTAD layer, spiro -OMeTAD:TMT-TTF (tetrakis(methylthio) tetrathiafulvalene) hybrid hole transport layer, and Au were the same as in our previous report . For AM 1.5 and 100 mW·cm –2 , the photovoltaic performance was measured using a solar simulator (Oriel, Newport) and a Keithley 2420 source meter controlled by Testpoint software.…”

Composition Engineering for the Content and Distribution of Sb–O, Se, S in Antimony Sulfoselenide Thin Films Using Chemical Bath Deposition for Efficient Solar Cells

“…The 40 nm‐thick CdS thin films were prepared according to our previous reports. [ 26 ] The spiro‐OMeTAD and spiro‐OMeTAD:TMT–TTF hole transport layer, Au electrode, and the measurements of SEM, XPS, EDS, and the photovoltaic performance were same as our previous reports. [ 24,25 ] The scanning step of XPS was 0.01 eV for Na 2 SSeO 3 (sodium mono/polyselenosulfate) and 0.05 eV for Sb 2 S y Se 3− y thin films.…”

Chemical bath deposition of Sb2S3 thin films using the mixing solution of SbCl3 and sodium citrate as a novel Sb source for assembling efficient solar cells

“…The CdS thin films were annealed at 400 1C for 10 min in air after the CdCl 2 methanol solution of 20 mg mL À1 was dropped and spin-coated at 3000 rpm for 30 s. The effect of spin coating CdCl 2 methanol solution was similar to the one mentioned in the literature. 19,20 Moreover, the measurements of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), ultraviolet-visible-near-infrared spectroscopy (UV-Vis-NIR), energy-dispersive spectrometry (EDS), atomic force microscopy (AFM) and the photovoltaic performance were the same as in our previous reports. [21][22][23]…”