Acid-Compatible Halide Perovskite Photocathodes Utilizing Atomic Layer Deposited TiO2 for Solar-Driven Hydrogen Evolution
Year: 2019
Type: article
Abstract: Although solution-processable halide perovskite semiconductors exhibit optoelectronic performance comparable to the best photoabsorbers for solar fuel production, halide perovskites rapidly decompose in the presence of water or even humid air. We show that a hybrid electron transport layer, a PC61BM + TiO2 film (18–40 nm thickness) grown over the sensitive absorber by atomic layer deposition, enables photoassisted proton reduction without further encapsulation. These semitransparent photocathodes, when paired with a Pt catalyst, display continuous reduction of H+ to H2 for hours under illumination, even while in direct contact with a strongly acidic aqueous electrolyte (0.5 M H2SO4). Under 0.5 Sun illumination, a photocurrent density of >10 mA cm–2 is observed, and a photovoltage of 0.68 V assists proton reduction, consistent with a structurally related photovoltaic (PV) device. Submersible halide perovskite photoelectrodes point the way to more efficient photoassisted overall water splitting and other solar fuel generation using solution-processed semiconductors with tunable band gaps.
Source: ACS Energy Letters
Institutions: Northwestern University, Argonne National Laboratory
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,000
Awards: G1794054907, G2743559567
OpenAlex ID: W2906867275
