Evaporated and solution deposited planar Sb₂S₃ solar cells: A comparison and its significance

Abstract

Sb2S3 is an alternative emerging material for chalcogenide solar cells. In this paper, we compare planar solar cells in which the Sb2S3 absorber was deposited by either thermal evaporation or a solution based process. The planar inorganic solar cell with evaporated Sb2S3 has an efficiency of 1.7%. This is much higher than the efficiency of 0.8% for solution deposited Sb2S3, and the highest known reported efficiency for a planar Sb2S3 solar cell with a CuSCN hole conducting layer. The evaporated Sb2S3 film is sulfur‐rich, which results in flattening of the film surface after annealing at 300 °C, thereby reducing the likelihood of contact between the Sb2S3 and gold contact. In addition, the crystal size of the evaporated Sb2S3 film is about 30% larger than that of the solution deposited Sb2S3 and has different preferential crystal planes. These features make evaporation a promising deposition method for flat solar cells made from sulfur‐based semiconducting materials. Cross section image of the evaporated Sb2S3 solar cell with labels for each layer.

Full‐Inorganic Thin Film Solar Cell and Photodetector Based on “Graphene‐on‐Antimony Sulfide” Heterostructure

“…Besides, sulfurization also improved the smoothness of the film surface. The non‐stoichiometric ratios of the Sb 2 S 3 layer may create traps and surface defects, which are likely to have a detrimental effect on the cell performance, especially for the sulfur deficient Sb 2 S 3 …”

“…[19,20] Among these methods, thermal evaporation is an attractive process that allows preparation of materials at large scale and can eliminate the impurity phase, avoid deep oxide defects, and reduce the time needed for crystal growth. [15] Nevertheless, the PCE of the Sb 2 S 3 solar cells prepared by thermal evaporation is still much lower than the best record (7.5%) that was obtained via the solution method. [21] The PCE of Sb 2 S 3 solar cells may be improved by reducing the hole-transport resistance in the device, as the recombination of photogenerated electrons and holes mostly occurs in the hole-transporting layer (HTL).…”

“…It has a suitable band gap for the absorption of visible light (from 1.7 to 2.2 eV depending on crystal size), along with a high absorption coefficient (α > 5 Â 10 4 cm À1 ). [5][6][7] Various approaches have been proposed to prepare Sb 2 S 3 thin films, including chemical bath deposition (CBD), [8][9][10][11] spray pyrolysis, [12,13] spin coating, [14] thermal evaporation, [15][16][17][18] and atomic layer deposition (ALD). [19,20] Among these methods, thermal evaporation is an attractive process that allows preparation of materials at large scale and can eliminate the impurity phase, avoid deep oxide defects, and reduce the time needed for crystal growth.…”

Spin-coated planar Sb2S3 hybrid solar cells approaching 5% efficiency

“…Solar cells with extremely thin absorber architecture [1–6 29] reach the highest efficiencies. Planar devices have been produced via various methods such as atomic layer deposition (ALD) [32], chemical bath deposition (CBD) [27] and (rapid) thermal evaporation (R)TE [33–35]. As the latest development, spin-coated planar solar cells [31,36–38] reached an efficiencies >4%.…”

Enhanced Photovoltaic Properties in Sb2S3 Planar Heterojunction Solar Cell with a Fast Selenylation Approach

“…Sb 2 S 3 has a low melting point (550 °C) and high vapor pressure, favoring thermal evaporation instead of magnetron sputtering. However, Sb 2 S 3 exhibits a poor thermostability in vacuum resulting in significant deviations in the composition [25], and the tendency for surface oxidation. Currently, component preserving rapid thermal evaporation (RTP) has been employed in the fabrication of all-inorganic Sb 2 S 3 solar cells having achieved a maximum PCE of 4.17% [23].…”