Sulfur Treatment Passivates Bulk Defects in Sb2Se3 Photocathodes for Water Splitting. (15th March 2022)

• Record Type: Journal Article
• Authors: Prabhakar, Rajiv Ramanujam; Moehl, Thomas; Friedrich, Dennis; Kunst, Marinus; Shukla, Sudhanshu; Adeleye, Damilola; Damle, Vinayaka H.; Siol, Sebastian; Cui, Wei; Gouda, Laxman; Suh, Jihye; Tischler, Yaakov R.; van de Krol, Roel; Tilley, S. David
• Is Part Of: Advanced functional materials. Volume 32:Number 25(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-15
• Subjects: charge carrier dynamics -- low‐frequency Raman spectroscopy -- photoluminescence spectroscopy -- Sb 2Se 3 -- time‐resolved microwave conductivity; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202112184
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Sb2 Se3 has emerged as an important photoelectrochemical (PEC) and photovoltaic (PV) material due to its rapid rise in photoconversion efficiencies. However, Sb2 Se3 has a complex defect chemistry, which reduces the maximum photovoltage. Thus, it is important to understand these defects and develop defect passivation strategies in Sb2 Se3 . A comprehensive investigation of the charge carrier dynamics of Sb2 Se3 and the influence of sulfur treatment on its optoelectronic properties is performed using time‐resolved microwave conductivity (TRMC), photoluminescence (PL) spectroscopy, and low‐frequency Raman spectroscopy (LFR). The key finding in this work is that upon sulfur treatment of Sb2 Se3, the carrier lifetime is increased by the passivation of deep defects in Sb2 Se3 in both the surface region and the bulk, which is evidenced by increased charge carrier lifetime of TRMC decay dynamics, increased radiative recombination efficiency, decreased deep defect level emission (PL), and the emergence of new vibration modes by LFR. Abstract : Time‐resolved microwave conductivity reveals that a low temperature sulfurization treatment reduces both surface and bulk recombination in thin film Sb2 Se3 ‐based photocathodes for photoelectrochemical water splitting. Photoluminescence shows an improved radiative recombination yield, and low‐frequency Raman spectroscopy indicates improved long‐range order in the films following sulfur treatment.