Energy Materials

At the Laboratory for Energy Materials (LEM) we are interested in making and testing complex materials necessary for energy conversion and storage using innovative methods. It is headed by
Prof Phillip Dale who also leads the doctoral training unit in advanced concepts for photovoltaics.

Currently our research is focused on the preparation and characterization of semiconductor layers for use in solar cells. We try to understand how to convert simple precursor layers into single phase high quality semiconductor materials suitable for devices that can efficiently convert incoming light into electrical power.

We are interested in small solar cells for semi-transparent, sensor, and high efficiency applications
Semiconductor precursor layers are synthesized electrochemically and by inkjet printing
We research both novel semiconductor materials and growth processes

JOB ANNOUNCEMENT - Post Doc

We have funding for a post doc position in the area of high speed annealing of compound semiconductors for solar cells. This ambitious highly collaborative inter-disciplinary project involves equipment testing, semiconductor synthesis and characterization. Current annealing times for semiconductor absorber layers are in the range of minutes to hours, and in this project we investigate how to reduce this to the timescale of seconds. Email phillip.dale@uni.lu for more information.

RECENT NEWS

September 2020 – Micro-sized thin film solar cells via a material efficient and area-selective electrodeposition

Micro-sized devices allow for the increase of power conversion efficiencies by employing concentrated sunlight into reduced absorber areas. Furthermore, using bottom-up strategies like area-selective electrodeposition allow for the reduction of the consumption of critical low- abundance raw materials like ln and Ga, used in the synthesis of the absorber CIGSe.

In this work, published in Scientific Reports, the assembly of micro-concentrator photovoltaic devices and the characterization of the absorber and device are presented. While controlling the local composition of electrodeposited layers into microelectrodes proved to be challenging, photovoltaic devices show open-circuit voltages of up to 525 mV under a light concentration factor of 18×. This value is larger than other reported Cu(In,Ga)Se₂ micro-solar cells fabricated by materials efficient methods.

August 2019 – New Youtube channel “Energy Balance” launched

In a new project, we are producing several videos explaining about the earth’s limited energy resources, and how we need to balance our energy consumption with production, in order to live sustainably without causing more global heating. The videos were designed so that they could be understood by everyone, especially for children, not just experts. The first two videos can be found here.

July 2019 - Phillip Dale part of the Solar Commission reporting on the role of photovoltaics in the UK

A new report championing the role of solar in the UK energy system, and the extensive expertise and innovation in UK companies and academia, was this week launched at the House of Lords. The report was produced by the Solar Commission and funded by UK Energy Research Centre (UKERC). Phillip Dale was part of this commission, and in addition he wrote a blogpost outlining why research into solar energy is still necessary. The publication was launched to a room of over 70 sector leaders and sustainable energy experts, with Joanna Whittington, director general for energy and security at Department for Business, Energy and Industrial Strategy welcoming the paper, which outlined areas where the UK could use its scientific and technical capabilities to play a leading role in innovation and industrial strategy opportunities in solar power.

March 2019 – Collaboration between UL and INL leads to micro solar cells for future light concentration applications

Normal solar cells are large, so that they capture as much light as possible. An alternative concept is to make them very small and use a lens to concentrate light onto them. This has the twin advantages of using less precious semiconductor and also increasing their efficiency.

In this joint paper between the group of Dr Sadewasser at the INL and Daniel Siopa of our group, we investigated the fabrication of such a small solar cell. Specifically we used electrodeposition to fabricate the part of the solar cell called the semiconductor absorber layer. Electrodeposition enables us to deposit small disks of metals inside an inert template which can then be converted by high temperature annealing into the semiconductor absorber layer. More details of the work can be found here .

Figure: Background image of micro-solar cell, foreground image of device efficiency as a function of illumination concentration factor and short circuit current.