Openings

We have 2 suggestions for Master projects.

MASTER PROJECT  6 months

Manufacturing energy systems on paper substrate

Looking for alternatives to manufacture paper-substrates solar cells, a new synthesis method called flash infrared annealing (FIRA) have the potential for the environmentally friendly multilayer growth processing1-3. This method is based on a thermal rapid annealing, which has been employed to synthesize thin films for semiconductor applications. FIRA allows preparing lead iodide PSCs with a record stabilized power conversion efficiency of 20%. With an irradiation time of fewer than 2 s, enables the coating of glass and plastic substrates with pinhole‐free perovskite films that exhibit micrometer‐size crystalline domains. Here, the main concept is to quickly heat up the material to control the crystallization kinetic without thermal degradation. This concept will be used for the next generation of thin film solar cells in paper substrates. This FIRA setup has been successfully used to synthesize highly crystalline organic-inorganic perovskite films, metal oxide semiconductor (e.g. TiO2 and NiO) and transparent inorganic conductive layers.

The project

FIRA has been used primarily for the preparation of perovskite solar cells, therefore this represent a step-forward for the preparation of paper-substrate stable solar cells, which will be used mainly for manufacturing dye and perovskite solar cells.Furthermore, with this project we propose the manufacturing of biocompatible energy systems, using the FIRA method.

Tasks

  1. Processing of solar cells on paper substrate with the FIRA method
  2. Characterization of thin films and devices with the basic analysis tools in the lab.

Details

Supervisor: Sandy Sánchez ([email protected])

Group: Prof. Anders Hagfeldt / LSPM

Time Frame: 6 months

Background: Basic chemistry or/and physics.

Applications

Full CV and motivation to be sent to Sandy Sánchez ([email protected])

References

  1. Sanchez, S.; Christoph, N.; Grobety, B.; Phung, N.; Steiner, U.; Saliba, M.; Abate, A., Efficient and Stable Inorganic Perovskite Solar Cells Manufactured by Pulsed Flash Infrared Annealing. Advanced Energy Materials 0 (0), 1802060.
  2. Sanchez, S.; Hua, X.; Phung, N.; Steiner, U.; Abate, A., Flash Infrared Annealing for Antisolvent-Free Highly Efficient Perovskite Solar Cells. Advanced Energy Materials, 1702915-n/a.
  3. Sánchez, S.; Vallés-Pelarda, M.; Alberola-Borràs, J.-A.; Vidal, R.; Jerónimo-Rendón, J. J.; Saliba, M.; Boix, P. P.; Mora-Seró, I., Flash infrared annealing as a cost-effective and low environmental impact processing method for planar perovskite solar cells. Materials Today 2019.

 

MASTER PROJECT  1-3 months

Ion Probe for Perovskite Solar Cells

Perovskite solar cells offer the promise of a cheap, renewable energy source. However, there are some major hurdles that need to be overcome before they can start to make an impact in the world. The largest obstacle in our path right now is their stability. While silicon solar cells, the ones you see on rooftops these days, retain at least 80% of their original efficiency after 20 years, even the best perovskite solar cells only last a few months.

Perovskite crystals are made from three constituent parts, often called A, B, and X. Unfortunately, it appears that it is quite easy for A and X atoms to break out of the crystal structure as ions, and move around. There is good evidence that this ion mobility enables a major pathway for this degradation. Understanding the dynamics of this movement better should reveal much needed insight in to how to prevent this degradation from occurring.

The project

In this experiment we aim to measure the dynamics of this ion movement directly, something that has never been done before. To do this, we place an electronic probe in the middle of the material, allowing us to measure voltage changes within it. Once we are able to get reliable measurements from the probe, no easy task in itself, we can begin to use it to measure how the internal voltage of the cell changes, and build a model of the dynamics within.

Tasks

  1. Tune the ion probe: We have already created a design for the ion probe, but have yet to get it working reliably. Your first task will be to modify the design so we can make reproducible measurements.
  2. Make some measurements: Once we have the ion probe dialed, we can start making measurements of the internal voltage change in the device.
  3. Build a model (Bonus): If we are able to get enough measurement data, we should be able to see some trends emerge, and draw some conclusions about how the ions move within the material. This will provide much needed insight into just how these mobile ions lead to degradation of the solar cells.

Details

Supervisor: Brian Carlsen ([email protected])

Group: Prof. Anders Hagfeldt / LSPM