Efficient Double Buffer Layer Sb₂ (Se_xS_1–x)₃ Thin Film Solar Cell Via Single Source Evaporation

Abstract

Sb2(SexS1–x)3 has been proven a very promising light absorbing material for photovoltaic applications due to its high stability, tunable band gap, non‐toxic element, and high extinction coefficient. For Sb2(SexS1–x)3 alloy film deposition, the authors develop a single source based rapid‐thermal‐evaporation (RTE) method instead of the traditional in‐situ sulfurization or double source co‐evaporation based RTE method. The absorber band gap can be precisely tuned from 1.1 to 1.7 eV by simply varying the molar ratio of Sb2Se3 and Sb2S3 source powder. From the systematical composition screening, FTO/CdS/Sb2(Se0.68S0.32)3/Au devices show higher power conversion efficiency (PCE ∼ 4.17%) when compared with other absorber compositions based devices. In order to achieve thinner ETL layers and simultaneously avoid pinholes led by rough FTO surface, we introduce for the first time double buffer layer in the Sb2(Se0.68S0.32)3 device system which could further improve the device efficiency from 4.17% to 5.73%. The double buffer layer ZnO/CdS helped to form graded energy band alignment, suppress charge recombination and efficiently extract electrons. The devices obtained higher Jsc and Voc supported by various physical characterization analyses. The facile single source deposition method, efficient double buffer layer device structure and notable PCE are expected to pronouncedly promote antimony chalcogenide device development.

An effective combination reaction involved with sputtered and selenized Sb precursors for efficient Sb2Se3 thin film solar cells

“…The series resistance (R) can be obtained by extrapolating the plots of dJ/dV against (J+J SC ) -1 to the Y-axis while the diode ideality factor (A) can be calculated as the slope of AkT/q (Figure 5c). [42] The series resistance and diode ideality factor were calculated to be R = 8.03 Ω/cm 2 configuration. [40,[43][44][45] It has been reported that such an interfacial layer between the absorber layer and Mo substrate with appropriate thickness could decrease the back contact barrier to improve the carrier transport and reduce the recombination loss.…”

Efficient Copper‐Doped Antimony Sulfide Thin‐Film Solar Cells via Coevaporation Method

“…[22,33] To understand the nature of dopant and its effect on Sb 2 S 3 energy levels, ultraviolet photoelectron spectroscopy (UPS) was conducted to investigate the energy level evolution. [23] The UPS spectra of Sb 2 S 3 and Cu-Sb 2 S 3 are shown in Figure 4a Figure 4c. These results demonstrated that our doped material was p-type and obtained a small up-shift in valance band (E v ).…”

“…In this study, we established a coevaporation method from Sb 2 S 3 and CuS mixture source to efficiently dope Sb 2 S 3 with copper via our previous RTE-based thin-film technique. [23] Using single-step deposition method, the fabricated films exhibited vertically oriented ribbons and large grains, which helped to reduce the recombination defects, whereas the other random orientations were significantly suppressed. The Cu doping can also reduce the resistivity and defect concentration, enhance carrier concentration, and balance the band offset between Sb 2 S 3 and Au, which profoundly improves J sc from 14.6 to 15.2 mA cm À2 and FF from 45.8% to 47.6%.…”

High Open‐Circuit Voltage in Full‐Inorganic Sb2S3 Solar Cell via Modified Zn‐Doped TiO2 Electron Transport Layer

“…In addition, using CdS as an ETL would slant to a sacrifice of short light absorption leading to a lower current density ( J SC ). [16] Recently, the encouraging results of Cd-free buffer layers such as SnO 2, [17] ZnO, [18] and TiO 2 [19] pave further research to overcome this inadequacy, where TiO 2 as ETL has been well-intentioned by promoting the epitaxial growth mechanism for Sb 2 S 3 films. [4] In the last decade, frequent cutting-edge investigations have advanced the TiO 2 /Sb 2 S 3 interface properties by doping in TiO 2 and its surface treatment.…”