News Article

GaAs Nanowires Harvest Solar Power

How can we harvest the energy of the sun at a better quality and at a cheaper cost?

To find out, Anna Fontcuberta and her team in the STI Laboratory of Semiconductor Materials (LMSC) at EPFL are working on novel solutions to produce the solar cells of tomorrow.

The research of Fontcuberta, a professor in the STI LSMCL, focuses on new ways to engineer semiconducting structures, mainly with the use of nanotechnologies.

Semiconductors, thanks to their physical properties, have increased the functionality of many objects in our daily lives (microwave ovens, cars, DVD player or computers e.g.) and at the same time our quality of life.

The LSMC works on new geometries using nanowires. These are needle-like crystals of a diameter between 20 and 100 nm and several microns long.

The objective is to increase their functionality by understanding their properties and finding new ways to fabricate them. Among the many applications using nanowires is one of a higher interest to Fontcuberta and her team: solar cells.

Because of the world's urgent need to harvest greener energies, nanowire solar cells have a huge societal and industrial potential for the future.

"We are working on nanowire solar cells using GaAs in their core, a high conducting material which absorbs light at the ideal range with respect to the solar spectrum", explains Fontcuberta.

For example, in the 1990's, GaAs solar cells took over from silicon devices in photovoltaic arrays for satellite applications, or power the robots that are exploring the surface of Mars.

In the LMSC,  gallium and arsenide atoms are engineered (or "tricked") in a way that they organise themselves to form wires rather than horizontal layer on layer structures (which they tend to do naturally).

This 3 dimensional geometry is a novelty as it enables the trapping of more light than planar structures, such as silicon solar devices, and with less material.

Each vertical nanowire becomes a device that produces current. The combination of the nanowires' small scale (one micron) and revolutionary 3D geometry (a little bit like hair standing up), enables a significant decrease of the solar cell's cost per watt - compared to commonly used solar cells.

Apart from enhancing the light absorbtion, Fontcuberta and her team are working on ways to optimise it. For example, they combine the nanowire's GaAs core with other nanoscale materials in both axial and radial directions. As an example, InAs quantum dots (or "islands") on the nanowire play the role of stimulants for a better absorbtion of the light.

An illustration of an example structure is shown below.

Nanowire solar cells represent the 3rd generation of solar cells because they are made on a very small scale and can be combined in many different ways, enabling the extraction of more energy at a lower cost.

Despite encouraging applications, "It might take ten more years before nanowires can be found on the market", explains Fontcuberta.

This is an objective, which the LMSC will pursue at EPFL.

From left to right, Francois Morier Genoud (Laboratory of Quantum Optoelectronics), Anna Fontcuberta and Emanuele Uccelli (Laboratory of Semiconductor Materials) in front of the MBE machine which is used for nanowire research, and which both groups share

Ingeteam The First Central Inverter Manufacturer To Be Certified To NTS UE 2016-631
Energeo Boosts Council’s Climate Emergency Plans
Eversheds Sutherland Advises On Europe’s Largest Floating Solar Project
US International Trade Commission Issues Final Determination Confirming No Infringement Of Hanwha Q-Cells Patent By REC Group
Van Der Valk Solar Systems And Eyecatcher BV Are Joining Hands!
Researchers Make Fuel From Cubic SiC, Graphene And CO2
REC Group Rejects Decision By The Düsseldorf Regional Court On Alleged Patent Infringement Regarding TwinPeak Solar Cells
Midsummer Solar Panels Are Ten Times Better For The Environment
Tesvolt Wins Leading Innovation Prize For SMEs
REC Group Top Performer In PV Module Reliability Scorecard By DNV GL
RES And SNCF Energie Sign A CPPA For Nearly 40 Megawatts Of Renewable Energy In France
PI Berlin Introduces Deep Dive Quality Assessment For Lithium-ion Battery Production
Meyer Burger Technology Ltd Aims To Transform Itself
REC Group Goes Virtual, Bringing Premium Solar Products
Vapour Fix Raises Perovskite Crystal Performance
REC Group Wins Prestigious Intersolar Award 2020 For Its Powerful Alpha Solar Panels
UK Breaks Record For Solar Energy Production In May
Solar Generates Savings On Your Electricity Bill − Irrespective Of The COVID-19 Crisis
Progress In Functional Roof Design: Photovoltaic In-roof System Combination
ENCAVIS And Sunovis Conclude A Cooperation Agreement For A 200 MW+ Portfolio Of Solar Projects In Germany
BYD Launches Battery-Box Premium LVS With Unparalleled Ease Of Use And Versatility For On- And Off-grid Installations
Obton Secures Subordinated Debt Facility For 30.4 MWp PV Portfolio In France
Midsummer’s Solar Panels Almost Ten Times More Environmentally Friendly Than A Typical Silicon Solar Panel
EnergyHub Partners With Vivint Solar To Expand Availability Of Residential Batteries As Utility Resources

Search the news archive

To close this popup you can press escape or click the close icon.
Register - Step 1

You may choose to subscribe to the Solar + Power Magazine, the Solar + Power Newsletter, or both. You may also request additional information if required, before submitting your application.

Please subscribe me to:


You chose the industry type of "Other"

Please enter the industry that you work in:
Please enter the industry that you work in: