New Paper – A Semiconductor-Mediator-Catalyst Artificial Photosynthetic System for Photoelectrochemical Water Oxidation
In fabricating an artificial photosynthesis (AP) electrode for water oxidation, we have devised a semiconductor-mediator-catalyst structure that mimics photosystem II (PSII). It is based on a surface layer of vertically grown nanorods of Fe2O3 on fluorine doped tin oxide (FTO) electrodes … Read more
New Paper – Design and characterization of surface molecular assemblies for the preparation of solar fuels
A key issue in solar energy conversion is the utilization of solar energy for the preparation of solar fuels. In this area, artificial photosynthesis offers promising approaches for the conversion of H2O and CO2 into usable solar fuels. This review … Read more
New Paper – An Iron Bis(carbene) Catalyst for Low Overpotential CO2 Electroreduction to CO: Mechanistic Insights from Kinetic Zone Diagrams, Spectroscopy, and Theory
A common challenge in molecular electrocatalysis is the relationship between maximum activity and the overpotential required to reach that rate, with faster catalysts incurring higher overpotentials. This work follows a strategy based on independent tuning of ligands in the primary … Read more
New Paper – Mixed Tin-Titanium Oxides by Atomic Layer Deposition on Planar Substrates: Physical and Electronic Structure
Ternary atomic layer deposition of Sn-doped TiOx (Sn:TiOx) and Ti-doped SnOx (Ti:SnOx) was performed using tetrakisdimethylamidotitanium (IV) and tin(IV) with water at 150 °C on (1 0 0) Si and quartz substrates. The physical structure of the films was investigated using scanning electron, atomic force, … Read more
New Paper – Influence of Surface and Structural Variations in Donor−Acceptor−Donor Sensitizers on Photoelectrocatalytic Water Splitting
Conjugated organic chromophores composed of linked donor (D) and acceptor (A) moieties have attracted considerable attention for photoelectrochemical applications. In this work, we compare the optoelectronic properties and photoelectrochemical performance of two D–A–D structural isomers with thiophene-X-carboxylic acid (X denotes 3 … Read more
New Paper – Polymer Chromophore-Catalyst Assembly for Photocatalytic CO2 Reduction
A polystyrene-based chromophore–catalyst assembly (PS-RuC/RuCat) was synthesized and applied for photocatalytic CO2 reduction in an organic solution in the presence of a sacrificial donor. The polymer assembly contains Ru(bpy)32+ (RuC, bpy = 2,2′-bipyridine) as the chromophore and a derivative of … Read more
New Paper – Interfacial Electron Transfer through Ultrathin ALD TiOX Layers: A Comparative Study of TiO2/TiOX and SnO2/TiOX Core/Shell Nanocrystals
Mesoporous anatase TiO2, mixed anatase/brookite TiO2, and rutile-type SnO2 nanocrystalline films were coated with ultrathin (<5 nm) TiOx by the atomic layer deposition (ALD) of tetrakisdimethylamidotitanium(IV) and water at 150 °C to fabricate SnO2/TiOx and TiO2/TiOx core/shell materials. The core/shell … Read more
New Paper – It Is Good to Be Flexible: Energy Transport Facilitated by Conformational Fluctuations in Light-Harvesting Polymers
We investigate the mechanism of energy transfer between ruthenium(II) (Ru) and osmium(II) (Os) polypyridyl complexes affixed to a polyfluorene backbone (PF-RuOs) using a combination of time-resolved emission spectroscopy and coarse-grained molecular dynamics (CG MD). Photoexcitation of a Ru chromophore initiates … Read more
New Paper – Dye-Sensitized Nonstoichiometric Strontium Titanate Core-Shell Photocathodes for Photoelectrosynthesis Applications
A core/shell approach that utilizes a high-surface area conducting core and an outer semiconductor shell is exploited to prepare p-type dye-sensitized solar energy cells that operate with a minimal applied bias. Photocathodes were prepared by coating thin films of nanocrystalline … Read more
New Paper – An Iron Pyridyl-Carbene Electrocatalyst for Low Overpotential CO2 Reduction to CO
Electrocatalysts for CO2 reduction based on first-row transition metal ions have attracted attention as abundant and affordable candidates for energy conversion applications. Yet very few molecular iron electrocatalysts exhibit high selectivity for CO. Iron complexes supported by a redox-active 2,2′:6′,2″-terpyridine … Read more
New Paper – Tunneling and Thermally Activated Electron Transfer in Dye-Sensitized SnO2|TiO2 Core|Shell Nanostructures
The mechanism for interfacial electron transfer (ET) from a metal oxide core|shell nanostructure to a [RuIII(2,2′-bipyridine)2(4,4′-(PO3H2)2-2,2′-bipyridine)]3+ sensitizer was probed through spectroscopic quantification of the ET kinetics over a 70 °C temperature range in an aqueous 0.1 M HClO4 solution. Mesoporous thin films … Read more
New Paper – Enabling Aqueous NiO Photocathodes by Passivating Surface Sites That Facilitate Proton-Coupled Charge Transfer
Photoelectrodes consisting of wide-band gap metal oxides functionalized with chromophores and catalysts are a potential low-cost solution to generate solar fuels from aqueous solution. NiO is a common photocathode material used in these systems, yet it generally exhibits poor performance … Read more
New Paper – Organic Chromophores Designed for Hole Injection into Wide-Band-Gap Metal Oxides for Solar Fuel Applications
The power conversion efficiency of tandem dye-sensitized photoelectrosynthesis cells is limited by the number of p-type metal oxide semiconductors and chromophores available for the photocathode. Here, a new class of donor–acceptor–donor organic chromophores is introduced with deep highest occupied molecular … Read more
New Paper – Solvent influence on non-adiabatic interfacial electron transfer at conductive oxide electrolyte interfaces
The kinetics for interfacial electron transfer (ET) from a transparent conductive oxide (tin-doped indium oxide, ITO, Sn:In2O3) to molecular acceptors 4-[N,N-di(p-tolyl)amino]benzylphosphonic acid, TPA, and [RuII(bpy)2(4,4′-(PO3H2)2-bpy)]2+, RuP, positioned at variable distances within and beyond the electric double layer (EDL), were quantified … Read more
New Paper – Perspectives on Dye Sensitization of Nanocrystalline Mesoporous Thin Films
Recent advances in our mechanistic understanding of dye-sensitized electron transfer reactions occurring at metal oxide interfaces are described. These advances were enabled by the advent of mesoporous thin films, comprised of anatase TiO2 nanocrystallites, that are amenable to spectroscopic and … Read more