Mixed‐Metal Tungsten Oxide Photoanode Materials Made by Pulsed‐Laser in Liquids Synthesis

Abstract

Globally scalable sunlight-driven devices that convert solar energy into storable fuels will require efficient light absorbers that are made of non-precious elements. Suitable photoanode materials are yet to be discovered. Here we utilised the timesaving nature of pulsed-laser in liquids synthesis and prepared a series of neat and mixed-metal tungsten oxide photoanode materials to investigate the effect of ad-metals on optical and photocurrent generation properties. We obtained sub-µm-sized materials with different colours from W, Al, Ta, or first-row transition metal targets in water or aqueous ammonium metatungstate solutions. We observed metastable polymorphs of WO3 and tungsten oxides with varying degrees of oxygen deficiency. Pulsed-laser in liquids synthesis of Ni in ammonium metatungstate solutions produced hollow spheres (with ≤ 6% Ni with respect to W). Photocurrent generation in strong aqueous acid was highest in mixed-metal tungsten oxide photoanode materials with around 5% of iron or nickel.

Water Oxidation Catalysts for Artificial Photosynthesis

“…After loading CoPi cocatalyst onto WO 3 , the Faraday efficiency for PEC oxygen evolution increases from 61 to 100%, indicating that the formation of peroxide on the CoPi/WO 3 photoanode was completely inhibited . In addition, a series of mixed‐metal WO 3 photoanodes were prepared by pulsed‐laser‐in‐liquids synthesis to investigate the effect of metal addition on optical and PEC activity . It was found that the mixed‐metal WO 3 photoanode with 5% Fe or Ni exhibited the best water oxidation performance.…”

Kinetically Stable Nonequilibrium Gold‐Cobalt Alloy Nanoparticles with Magnetic and Plasmonic Properties Obtained by Laser Ablation in Liquid

“…To provide a solution to most of the above problems, the laser ablation synthesis in solution (LASiS) has been intensely applied and optimized in the last years, resulting in a large library of nanomaterials, [23–28] that includes various equilibrium and nonequilibrium nanoalloys like Fe−Mn, [29] Ag−Cu, [30] Pt−Cu, [31] Co−Al, [32] Au−Fe, [18,33] Ag−Fe, [34] Ag−Co, [35] as well as ternary, quaternary and quinary systems [36] or high‐entropy alloys [37] . The LASiS is scalable up to g/h of NPs, [38] is amenable of automatization and can be controlled also remotely with a PC or a smartphone, [39] thus reducing all risks connected to the laser sources, harmful or explosive compounds.…”

Mechanism of Laser-Induced Bulk and Surface Defect Generation in ZnO and TiO2 Nanoparticles: Effect on Photoelectrochemical Performance

“…Pulsed lasers are powerful tools for the time-efficient preparation and/or modification of functional materials. − Recent investigations have shown that laser-modified TiO 2 particles can be used to improve the light-driven water splitting to form hydrogen or rhodamine B degradation . Irradiation by ns–532 nm pulses yielded sub-micrometer TiO 2 spheres, SMS .…”