Anionic Disorder and Its Impact on the Surface Electronic Structure of Oxynitride Photoactive Semiconductors
The conversion of solar energy into chemical energy, stored in the form of hydrogen, bears enormous potential as a sustainable fuel for powering emerging technologies. Photoactive oxynitrides are promising materials for splitting water into molecular oxygen and hydrogen. However, one of the issues limiting widespread commercial use of oxynitrides is degradation during operation. While recent studies have shown the loss of nitrogen, its relation to reduced efficiency has not been directly and systematically addressed with experiments. In this study, we demonstrate the impact of the anionic stoichiometry of BaTaOxNy on its electronic structure and functional properties. Through experimental ion scattering, electron microscopy, and photoelectron spectroscopy investigations, we determine the anionic composition ranging from the bulk toward the surface of BaTaOxNy thin films. This further serves as input for band structure computations modeling the substitutional disorder of the anion sites. Combining our experimental and computational approaches, we reveal the depth-dependent elemental composition of oxynitride films, resulting in downward band bending and the loss of semiconducting character toward the surface. Extending beyond idealized systems, we demonstrate the relation between the electronic properties of real oxynitride photoanodes and their performance, providing guidelines for engineering highly efficient photoelectrodes and photocatalysts for clean hydrogen production.
Taking off with sustainable kerosene
Researchers around the world are working to find and optimise new ways of producing climate-neutral aviation fuel. At PSI, together with industry, they’re exploring a promising approach.
A complex promise
There’s more to climate-neutral aviation than just reducing emissions during flights. A PSI study analyses what is needed to achieve this long-term goal.
iLab and Synfuels at the Energy Days! at the Swiss Museum of Transport
October 18, 19, and 20, 2024
The iLab from the Paul Scherrer Institute will be part of the Energy Days with exciting workshops. Discover how we can store renewable energy using innovative technologies like Power-to-Gas and drive the energy transition forward.
Where should hydrogen be produced in the future?
Researchers at PSI have been looking into where the hydrogen for a future hydrogen economy should be produced and what impact this energy carrier will have on the environment.
Sustainable aviation fuel from the PSI campus
In collaboration with climate start-up Metafuels, a pilot plant for the production of sustainable aviation fuel is being set up on the PSI campus.
Promotion versus Poisoning in Copper–Gallium-Based CO2-to-Methanol Hydrogenation Catalysts
Cu–Ga-based CO2-to-methanol hydrogenation catalysts display a range of catalytic performance, depending on their preparation. Here, we investigated how the Ga/Cu ratio and Ga speciation affect the catalytic activity. Using surface organometallic chemistry, we prepared a series of silica-supported 3–6 nm Cu1–xGaxOy nanoparticles with a range of xGa. The materials display a volcano-type activity behavior, where methanol formation is promoted when xGa < 0.13–0.18 and is suppressed at higher values, indicating a poisoning of the catalysts. In situ X-ray absorption spectroscopy and in situ infrared spectroscopy helped to understand the structure-activity relationship.
How clean is hydrogen for the energy transition?
Hydrogen can play a crucial role in transitioning to a net-zero energy system – but it must be produced the right way.
Methane as an energy store
Researchers at PSI and the start-up AlphaSYNT are working together on a solution for efficiently storing energy.
A greener alternative for aviation fuel
Air travel with no carbon footprint – PSI and the Metafuels AG develop a new technology to produce sustainable aviation fuel.
Energy efficiency in times of potential power shortages
How PSI is continuously improving the energy efficiency of its own infrastructure and large research facilities
Preparing for energy shortages and blackouts
Peter Burgherr is a risk researcher at PSI. In this interview he talks about possible power shortages in the coming winter and how to prepare for them.
Manure and slurry are underused energy resources
Animal manure is packed with energy that is hugely underutilised. So concludes a white paper by Swiss bioenergy researchers.
Getting maximum energy out of biomass
Researchers at the Paul Scherrer Institute PSI start operation of a revolutionary pilot plant for production of synthetic biogas.
Effectively removing CO2 from the atmosphere
With careful planning, effective CO2 capture is technically possible.
“Without these technologies, we will hardly achieve our climate targets”
To achieve carbon neutrality, technologies need to be deployed which remove carbon dioxide from the atmosphere.
Green fuels for aviation
In a new initiative, PSI and Empa want to jointly develop a process for producing kerosene from renewable resources.
Foundations for the energy system of tomorrow
On the way to a sustainable energy system, technologies that help to flexibly convert and efficiently store energy are becoming increasingly important. ReMaP, a novel research platform, aims to investigate these urgent issues under realistic conditions.
Clean biogas for a successful energy transition
PSI researchers have set up camp at a biogas plant near Lucerne. Between meadows and gigantic fermenters, they are investigating how they can remove impurities from the biogas to make this energy source even more usable.
Life cycle assessment of cars – new web tool helps consumers and researchers
Decision support for car buyers: Researchers at the Paul Scherrer Institute have developed a web tool called the Carculator that can be used to compare the environmental performance of passenger cars in detail.
Long-term developments of energy pricing and consumption in industry
Researchers from the Paul Scherrer Institute PSI, on behalf of a research project funded by the Swiss Federal Office of Energy (SFOE), have studied how energy consumption by Swiss industry develops depending on energy prices. One result: Price increases for energy usually affect energy consumption only over the long term.
"Electric is already the right choice today"
An interview on automotive power systems with Christian Bauer, a scientist at PSI's Laboratory for Energy Systems Analysis who specialises in life cycle and sustainability analyses.
Make way for electric cars
Petrol, diesel, fuel cell or electric – which is the automobile of the future? A PSI study has examined the overall climate impact of various vehicle engines in use today and also projected it to the year 2040.
Toward better motors with X-ray light
Making Switzerland's road traffic fit for the future calls for research, first and foremost. In the large-scale research facilities of PSI, chemists and engineers are investigating how to improve the efficiency of motors and reduce their emissions.
"This is incredibly ambitious"
Every three years, the World Energy Council explores possible developments of the global energy system under different scenarios. Tom Kober, head of the Energy Economics Group in PSI’s Laboratory for Energy Systems Analysis and one of the lead authors of the study, explains what the individual scenarios mean and how global warming could be mitigated.
The energy system of the future and Power-to-X
Researchers at the Paul Scherrer Institute PSI analyse the potential of Power-to-X for Switzerland's energy supply and present their conclusions in a white paper. One finding: The costs for energy from Power-to-X could fall by up to one-third.
Testing the energy system of the future today, as realistically as possible
With the kick-off of the ReMaP project, companies have another opportunity to test their vision for the energy system of the future now. PSI's ESI platform helps to make better and more intelligent use of renewable energy in the future.
Power on demand
If photovoltaic or wind power plants produce more electricity than the network can absorb, valuable energy is lost. At the ESI Platform, PSI researchers are investigating how fuel cells can contribute to making this energy usable in a targeted way through storage.
Profitable for both sides
The young company Swiss Hydrogen is located in Fribourg. Here work is under way on competitive high-performance fuel cells that could be used in environmentally friendly vehicles or deployed as stationary power generators. In the company's collaboration with PSI, as CEO Alexandre Closset explains in this interview, both sides profit.
New technology undergoes real-world testing
The Zurich-based power company Energie 360° provides natural gas, biogas, and wood pellets throughout Switzerland. Now, with the Paul Scherrer Institute PSI, it has successfully tested a new Power-to-Gas technology to be implemented in the area of biogas production. The joint project was awarded the Swiss energy prize Watt d'Or 2018. In this interview, division manager Peter Dietiker talks about the collaboration with PSI.
Using what's there
At the Paul Scherrer Institute PSI, researchers are looking for solutions that enable energy from the sun, the wind, or biomass to be efficiently integrated into the Swiss energy system.
Efficient energy from biowaste – Watt d'Or for PSI and Energie 360°
Efficiently producing energy from biowaste: A technology developed at PSI and tested in collaboration with the Zurich-based energy provider Energie 360° makes it possible. It extracts significantly more methane from biowaste than conventional methods. For this important contribution to a sustainable energy supply, PSI and Energie 360° have now been awarded the Watt d'Or 2018 in the Renewable Energy category by the Swiss Federal Office of Energy.
Stress test passed
With a technology developed at the Paul Scherrer Institute PSI, around 60 percent more biogas can be produced from bio-waste than with conventional methods. But can it stand the test in practice as well? A 1,000-hour test at the Werdhölzli biowaste digestion and wastewater treatment plant in Zurich was able to answer this question with a clear yes. It was carried out in cooperation with the Zurich-based energy provider Energie 360°. The analysis of the stress test is now available.
More than just spilling the beans
Because of their high nitrogen content, spent coffee grounds are a popular garden fertilizer. Recycled in this manner, they already contribute to an environmentally friendly waste management. But they have the potential to deliver much more: a new procedure developed at the PSI allows high quality methane to be formed from spent coffee grounds. PSI researchers involved in a pilot project carried out in cooperation with the Swiss food producer Nestlé were able to show that spent coffee grounds left over during the production of instant coffee can be efficiently re-used elsewhere.
Nanomaterial helps store solar energy: efficiently and inexpensively
Efficient electrolysers are needed in order to store sun and wind energy in the form of hydrogen. Thanks to a new material developed by researchers at the Paul Scherrer Institute PSI and Empa, these devices are likely to become less costly and more efficient in the future. Researchers were also able to demonstrate that this new material can be reliably produced in large quantities, showing its performance capability in an electrolysis cell—the main component of an electrolyser.
Welcome to Esiville
A new visitor’s station at PSI tells the story of a Swiss town that makes the change from a conventional energy supply to one with new renewable energy sources.
How Switzerland could supply its electric power in 2050
The Laboratory for Energy Systems Analysis at the Paul Scherrer Institute PSI is investigating how Switzerland’s electricity supply might look, up to the year 2050, under a variety of boundary conditions. On the basis of their calculations, the lab’s researchers are able to generate insights on possible future developments of the energy sector, for example, determine how an ambitious reduction in CO2 emissions could be achieved at the lowest possible cost.
Higher methane yield from bio-waste
Within Switzerland’s bio-waste a huge amount of precious energy is hidden. That’s because valuable methane, the main constituent of natural gas, can be obtained from it. With a technology developed at PSI, the yield of methane from bio-waste could be increased considerably in the future. A long-term test conducted in cooperation with Energie 360° at the Werdhölzli fermentation and wastewater treatment plant is expected to advance this technology further along its path to industrial use.
24 hours at the ESI Platform (video)
How can surplus power that can’t be fed into the electric grid be made usable? A fictitious day at the Energy System Integration Platform at the Paul Scherrer Institute PSI.
Renewable energy: Experimental platform ESI is starting up
This fall, the time has come: The Energy System Integration Platform at the Paul Scherrer Institute PSI goes into operation. Today, in the framework of the double conference Networked Energy Research Switzerland, it was presented to the media and around 150 representatives from politics, industry, and science.
Sun-Petrol
Despite its great potential, solar energy still faces one big problem: the sun doesn’t always shine and its energy is hard to store. Now, researchers at the Paul Scherrer Institute PSI and the ETH Zurich have unveiled a chemical process that uses the sun’s thermal energy to convert carbon dioxide and water directly into high-energy fuels: a procedure developed on the basis of a ground-breaking material combination of cerium oxide and rhodium.
Turning Electricity into Gas – and back into Electricity
As capacities for producing solar and wind energy increase, integrating these into the existing energy system is becoming more of a challenge. The ESI platform is testing methods for successful integration. The answer: storing surplus energy as gas.
Water pathways make fuel cells more efficient
Researchers from the Paul Scherrer Institute (PSI) have developed a coating technique in the laboratory conditions that could raise the efficiency of fuel cells. The PSI scientists have already applied to patent the technique, which is suitable for mass production.
Biomasse als Stütze der Energiewende
Mit 80 Teilnehmerinnen und Teilnehmern fand am 2. Dezember am Paul Scherrer Institut PSI die erste Jahreskonferenz des Kompetenzzentrums des Bundes für Bioenergie (SCCER BIOSWEET) statt. Das im Rahmen des Aktionsplans Energieforschung Schweiz gegründete Kompetenzzentrum definierte in der Tagung die Ziele, Strategien und Positionierung der Bioenergie-Forschung vor dem Hintergrund der neuen schweizerischen Energiepolitik.This news release is only available in German.
New Renewables on integration course
The Swiss government’s Energy Strategy 2050 includes a significant expansion of renewable energy such as solar and wind power. The integration of this electric energy, which is produced in a decentralised way and with temporal fluctuations, poses a major challenge for power grids. One possible solution involves using the electricity surplus that would otherwise overload the grid for the production of gases such as hydrogen or methane. The electric energy would thus be stored temporarily in form of chemical energy. These gaseous energy carriers can be converted back into electricity, heat or kinetic energy (in gas engines) at a later date as and when needed. Dubbed power to gas, the concept is the focus of the new Energy System Integration (ESI) Platform at PSI.
Joint venture in the bioenergy and resource efficiency sector: PSI and FHNW establish joint institute
The Institute of Biomass and Resource Efficiency was founded by the two institutions, PSI (Paul Scherrer Institute) and FHNW (University of Applied Sciences Northwestern Switzerland), at the start of 2013. The aim of this new institute is to tackle the issue of resource efficiency throughout Switzerland, concentrating simultaneously on energy and material for the first time, and to thus make a significant contribution to the Federal Government’s "Energy Strategy 2050". The focus is on the sustainable use of biomass.
«Facettenauge» liefert Strom
«swisselectric research award 2011»Kostengünstiger Strom aus Sonnenenergie: Der Maschinenbauingenieur Illias Hischier hat einen Sonnenstrahlempfänger entwickelt, der die aufgenommene Energie über eine Gasturbine für die hocheffiziente Stromerzeugung nutzt. Hischier hat den Empfänger als Doktorand an der ETH Zürich in Zusammenarbeit mit dem Labor für Solartechnik am Paul Scherrer Institut entwickelt. Er erhält dafür den «swisselectric research award 2011».This news release is only available in German.
Benzin aus Wasser, CO2 und Sonnenlicht
Einem Forschungsteam um Aldo Steinfeld ist es gelungen, mit Solarenergie aus Wasser und Kohlendioxid Treibstoff zu erzeugen. Dazu haben die Wissenschaftler einen Solar-Reaktor entwickelt, in dem konzentrierte Sonnenstrahlung das dafür nötige thermochemische Verfahren antreibt.This news release is only available in German.