Surface‐Passivated Vertically Oriented Sb₂S₃ Nanorods Photoanode Enabling Efficient Unbiased Solar Fuel Production

Abstract

The lack of highly efficient photoanodes presents a significant challenge to implementing the promising strategy of unbiased solar‐to‐fuel conversion. To achieve high‐performance photoanodes, improving their light harvesting and charge separation/injection capabilities is indispensable. Herein, solution‐processed vertically oriented Sb2S3 nanorod arrays on substrate are obtained via a Au seed layer, resulting in improved optoelectronic properties (due to the light scattering effect) and favorable crystallographic orientation of the 1D nanostructure. Moreover, the (NH4)2WS4 treatment caps the surface of the nanorods with an amorphous WSx layer and passivates the sulfur vacancy of Sb2S3, resulting in boosted charge extraction to the reactants. The resulting photoanode is employed to drive an iodide oxidation reaction (IOR), which is a prominent alternative to sluggish water oxidation reactions, exhibiting a high photocurrent density of 13 mA cm−2 at 0.6 V versus the reversible hydrogen electrode. Subsequently, an unassisted hydrogen generation device is demonstrated by combining an Sb2S3 nanorod array‐based photoanode for IOR and a perovskite‐based photocathode for the hydrogen evolution reaction, achieving an efficient hydrogen production current density of 5.7 mA cm−2 without any external bias.

Photoilluminated Redox-Processed Rh2P Nanoparticles on Photocathodes for Stable Hydrogen Production in Acidic Environments

“…A notable approach in this field is the utilization of photoelectrochemical (PEC) water splitting, which is well regarded for its environmentally friendly hydrogen generation using abundant water and sunlight. − Recent advancements have introduced photoactivation layers based on metal oxides, ,, selenide, , Si, − and perovskite materials, − leading to significant enhancements in solar-to-hydrogen (STH) efficiency. Moreover, the development of various functional multistacked layers presents innovative approaches to improve carrier mobility and suppress charge recombination at the interfaces. − However, despite this progress, the technical challenge regarding low STH efficiency still poses a practical application barrier. , In particular, for photocathodes using p-type semiconductors, research approaches to the enhancement of STH values have focused on the combined improvements of photoabsorbers and protection layers up to now. , …”

Large-area all-perovskite-based coplanar photoelectrodes for scaled-up solar hydrogen production

“…1–3 Over the past few decades, various strategies such as morphology control, band alignment, and interfacial engineering have been used for fabricating photoelectrodes for PEC water splitting systems. 2,4–11 Yet, the use of PEC devices is not widespread because of their high fabrication cost, low performance and poor stability, along with the absence of large-scale deployment. 12 Recently, the development of lead halide perovskite (LHP)-based integrated photoelectrodes has helped overcome these drawbacks and has facilitated unbiased PEC water splitting, resulting in the achievement of a high solar-to-hydrogen (STH) efficiency exceeding 13% with high stability, encouraged by various encapsulation methods.…”

Fabrication of Flower-Shaped Sb2S3/Fe2O3 Heterostructures for Enhanced Photoelectrochemical Performance

“…However, very few reports have used Sb 2 S 3 as the main component of a photoanode for decomposing water, mainly due to its relatively fast degradation, surface defects, low electron–hole separation efficiency, and poor carrier transport . To overcome these issues, strategies such as morphology control, surface modification, doping, and constructing heterojunctions ,,− have been proposed. In general, the Sb 2 S 3 photoanode is still in its infancy and needs further development and exploration.…”