A5049436294- Advanced Photocatalysis Techniques
- Electrocatalysts for Energy Conversion
- Semiconductor materials and devices
- TiO2 Photocatalysis and Solar Cells
- Copper-based nanomaterials and applications
- Advanced MEMS and NEMS Technologies
- Ga2O3 and related materials
- Advanced Sensor and Energy Harvesting Materials
- Metal Forming Simulation Techniques
- Metallurgy and Material Forming
- Electrical and Thermal Properties of Materials
- Electron and X-Ray Spectroscopy Techniques
- CO2 Reduction Techniques and Catalysts
- Aluminum Alloys Composites Properties
- Ferroelectric and Piezoelectric Materials
- Catalytic Processes in Materials Science
- Acoustic Wave Resonator Technologies
- Advanced Sensor Technologies Research
- Microstructure and mechanical properties
- Electronic and Structural Properties of Oxides
- Ammonia Synthesis and Nitrogen Reduction
- Innovative Microfluidic and Catalytic Techniques Innovation
- Electrochemical Analysis and Applications
- Powder Metallurgy Techniques and Materials
- Energy Harvesting in Wireless Networks
Technical University of Denmark
2010-2023
Ørsted (Denmark)
2012-2018
Danish Geotechnical Society
2016
University of Copenhagen
2007
Norsk Hydro (Germany)
2006
Danfoss (Denmark)
2000
Surface passivation is a general issue for Si-based photoelectrodes because it progressively hinders electron conduction at the semiconductor/electrolyte interface. In this work, we show that sputtered 100 nm TiO2 layer on top of thin Ti metal may be used to protect an n+p Si photocathode during photocatalytic H2 evolution. Although semiconductor, behaves like metallic conductor would under photocathodic evolution conditions. This behavior due fortunate alignment band with respect hydrogen...
A low-cost substitute: titanium protection layer on silicon made it possible to use under highly oxidizing conditions without oxidation of the silicon. Molybdenum sulfide was electrodeposited Ti-protected n(+)p-silicon electrode. This electrode applied as a photocathode for water splitting and showed greatly enhanced efficiency.
This study highlights the feasibility to scale-up photoelectrochemical water splitting TW level using Pt nanoparticles as hydrogen evolution catalyst.
Solar rechargeable flow cells (SRFCs) provide an attractive approach for in situ capture and storage of intermittent solar energy via photoelectrochemical regeneration discharged redox species electricity generation. However, overall SFRC performance is restricted by inefficient reactions. Here we report efficient SRFC based on a dual-silicon cell quinone/bromine battery conversion storage. Using narrow bandgap silicon photon collection fast couples rapid interface charge injection, our...
The semiconducting materials used for photoelectrochemical (PEC) water splitting must withstand the corrosive nature of aqueous electrolyte over long time scales in order to be a viable option large scale solar energy conversion. Here we demonstrate that atomic layer deposited titanium dioxide (TiO2) overlayers on silicon-based photocathodes generate extremely stable electrodes. These electrodes can produce an onset potential +0.510 V vs. RHE and hydrogen evolution saturation current 22 mA...
Sputter deposition of Ir/IrOx on p(+)-n-Si without interfacial corrosion protection layers yielded photoanodes capable efficient water oxidation (OER) in acidic media (1 M H2SO4). Stability at least 18 h was shown by chronoamperomety 1.23 V versus RHE (reversible hydrogen electrode) under 38.6 mW/cm(2) simulated sunlight irradiation (λ > 635 nm, AM 1.5G) and measurements with quartz crystal microbalances. Films exceeding a thickness 4 nm were to be highly active though metastable due an...
Sputter deposition of 50 nm thick NiO films on p(+)-n-Si and subsequent treatment in an Fe-containing electrolyte yielded highly transparent photoanodes capable water oxidation (OER) alkaline media (1 M KOH) with high efficiency stability. The Fe thin enabled Si-based photoanode assemblies to obtain a current density 10 mA/cm(2) (requirement for >10% efficient devices) at 1.15 V versus RHE (reversible hydrogen electrode) under red-light (38.6 mW/cm(2)) irradiation. Thus, the were harvesting...
Stabilizing efficient photoabsorbers for solar water splitting has recently shown significant progress with the development of various protection layers. Suitable layers tandem devices should be conductive, transparent, and stable in strongly acidic or alkaline solutions. This paper shows that under certain conditions n-type semiconductors, such as TiO2, can used Si-based photoanodes. It also provides evidence even a photoanode assembly TiO2 is conducting only electrons (not holes p-type...
A new MoS2 protected n+p-junction Si photocathode for the renewable H2 evolution is presented here. acts as both a protective and an electrocatalytic layer, allowing at 0 V vs. RHE more than 5 days. Using MoSx surface layer decreases overpotential by 200 mV.
We present the first experimental demonstration of c-Si based photocathode for hydrogen production under back-illumination with theoretical model study.
Rh2−yCryO3/GaN:ZnO has been tested for gas phase overall photocatalytic water splitting by dosing vapor. The sample deposited in a μ-reactor and evolves hydrogen oxygen under illumination of solar light. This experiment proves the possibility to study active materials mechanism reaction with experiments. high impact relative humidity on activity shown changing partial pressure reactor temperature.
A solar-to-chemical conversion process is demonstrated using a photoelectrochemical cell without external bias for selective oxidation of hydrogen sulfide (H2S) to produce peroxide (H2O2) and sulfur (S). The integrates two redox couples anthraquinone/anthrahydroquinone I−/I3−, conceptually illustrates the remediation waste product producing valuable chemicals.
The electrocatalytic performance for hydrogen evolution has been evaluated radial-junction n+p-Si microwire (MW) arrays with Pt or cobalt phosphide, CoP, nanoparticulate catalysts in contact 0.50 M H2SO4(aq). CoP-coated (2.0 mg cm–2) MW photocathodes were stable over 12 h of continuous operation and produced an open-circuit photovoltage (Voc) 0.48 V, a light-limited photocurrent density (Jph) 17 mA cm–2, fill factor (ff) 0.24, ideal regenerative cell efficiency (ηIRC) 1.9% under simulated 1...
The present work demonstrates that tuning the donor density of protective TiO2 layers on a photocathode has dramatic consequences for electronic conduction through with implications stabilization oxidation-sensitive catalysts surface. Vacuum annealing at 400 °C 1 hour atomic layer deposited increased from an as-deposited value 1.3 × 1019 cm−3 to 2.2 1020 following step. Using Fe(II)/Fe(III) redox couple it was shown lower dopant only allows electron transfer under conditions weak band...
We have studied the magnetic properties of 57Fe-doped NiO nanoparticles using Mössbauer spectroscopy and magnetization measurements. Two samples with different degrees interparticle interaction were studied. In both particles characterized by high-resolution transmission electron microscopy x-ray diffraction found to be plate-shaped. Computer simulations showed that high-field data are very sensitive size uncompensated moment. From analyses spectra we estimated moment is in accordance a...
This paper presents a novel apparatus for extracting volatile species from liquids using "sniffer-chip." By ultrafast transfer of the through perforated and hydrophobic membrane into an inert carrier gas stream, sniffer-chip is able to transport directly mass spectrometer narrow capillary without use differential pumping. method inherits features electrochemical spectrometry (DEMS) inlet (MIMS), but brings best both worlds, i.e., fast time-response DEMS system high sensitivity MIMS system....