Visible light-assisted instability of kesterite Cu2ZnSnS4: What are the implications?

A Novel Thermochemical Metal Halide Treatment for High-Performance Sb2Se3 Photocathodes

“…Therefore, cheap and eco-friendly wide-bandgap metal oxides such as TiO 2 , BiVO 4 , or Fe 2 O 3 are considered inappropriate for the bottom electrode, requiring a narrow bandgap semiconductor. Over the last decades, different cost-effective metal chalcogenides such as Nanomaterials 2021, 11,52 2 of 14 tin sulfide (SnS, E g~1 .3 eV) [6,14] and copper-zinc-tin-sulfide (CZTS, E g~1 .5 eV) [10,15] or metal oxide materials, e.g., CuFeO 2 (E g~1 .5 eV) [16] have been tried with limited success. Although the optoelectronic properties of CZTS give the impression of being suitable for the bottom photoelectrode, the low photocorrosion stability restrains its applicability in commercial PEC water splitting devices [10].…”

“…Over the last decades, different cost-effective metal chalcogenides such as Nanomaterials 2021, 11,52 2 of 14 tin sulfide (SnS, E g~1 .3 eV) [6,14] and copper-zinc-tin-sulfide (CZTS, E g~1 .5 eV) [10,15] or metal oxide materials, e.g., CuFeO 2 (E g~1 .5 eV) [16] have been tried with limited success. Although the optoelectronic properties of CZTS give the impression of being suitable for the bottom photoelectrode, the low photocorrosion stability restrains its applicability in commercial PEC water splitting devices [10]. Thus, alternative semiconductors, which could meet the PEC water splitting process requirements, are pressingly needed to reach the practical STH efficiency [10,12].…”

“…Inorganic TFSCs have recently demonstrated remarkable power conversion efficiencies (PCE): 23.35% for the copper-indium-gallium-selenide (CIGS) technology in 2019 [ 2 ], or 22% for cadmium telluride (CdTe) in 2017 [ 3 ]; and the PEC cells exploiting III–V photovoltaic materials reached a solar-to-hydrogen (STH) efficiency of 19.3% in 2018 [ 4 ]. Since the availability and toxicity of the constituent elements in these technologies limit the production potential, the investigation of inexpensive and nontoxic absorbers with relevant optoelectronic properties becomes paramount [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ].…”

“…Although the optoelectronic properties of CZTS give the impression of being suitable for the bottom photoelectrode, the low photocorrosion stability restrains its applicability in commercial PEC water splitting devices [ 10 ]. Thus, alternative semiconductors, which could meet the PEC water splitting process requirements, are pressingly needed to reach the practical STH efficiency [ 10 , 12 ].…”

“…Antimony (III) selenide (Sb 2 Se 3 ) has recently emerged as an eco-compatible and low-cost absorber material for various photo-assisted applications due to its advantageous optoelectronic properties ( E g ~1.2 eV, absorption coefficient > 10 5 cm −1 , high mobility) [ 7 , 17 , 18 , 19 , 20 , 21 ]. Besides, Sb 2 Se 3 is internally stable towards photocorrosion, and its elemental composition suggests less-complicated chemistry within the device processing compared to the multielement compounds such as CIGS and CZTS [ 7 , 10 , 22 ]. All these signs indicate the great potential of Sb 2 Se3 for commercial high-performance PEC water splitting devices.…”