Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Crystal light: New light-converting materials point to cheaper, more efficient solar power

30.01.2015

University of Toronto engineers study first single crystal perovskites for new solar cell and LED applications

University of Toronto engineers study first single crystal perovskites for new applications Engineers have shone new light on an emerging family of solar-absorbing materials that could clear the way for cheaper and more efficient solar panels and LEDs.


This is a pure perovskite crystal, orange in colour, is mounted on a cryostat.

Credit: U of T Engineering

The materials, called perovskites, are particularly good at absorbing visible light, but had never been thoroughly studied in their purest form: as perfect single crystals.

Using a new technique, researchers grew large, pure perovskite crystals and studied how electrons move through the material as light is converted to electricity.

Led by Professor Ted Sargent of The Edward S. Rogers Sr. Department of Electrical & Computer Engineering at the University of Toronto and Professor Osman Bakr of the King Abdullah University of Science and Technology (KAUST), the team used a combination of laser-based techniques to measure selected properties of the perovskite crystals. By tracking down the rapid motion of electrons in the material, they have been able to determine the diffusion length--how far electrons can travel without getting trapped by imperfections in the material--as well as mobility--how fast the electrons can move through the material. Their work was published this week in the journal Science.

"Our work identifies the bar for the ultimate solar energy-harvesting potential of perovskites," says Riccardo Comin, a post-doctoral fellow with the Sargent Group. "With these materials it's been a race to try to get record efficiencies, and our results indicate that progress is slated to continue without slowing down.."

In recent years, perovskite efficiency has soared to certified efficiencies of just over 20 per cent, beginning to approach the present-day performance of commercial-grade silicon-based solar panels mounted in Spanish deserts and on Californian roofs.

"In their efficiency, perovskites are closely approaching conventional materials that have already been commercialized," says Valerio Adinolfi, a PhD candidate in the Sargent Group and co-first author on the paper. "They have the potential to offer further progress on reducing the cost of solar electricity in light of their convenient manufacturability from a liquid chemical precursor."

The study has obvious implications for green energy, but may also enable innovations in lighting. Think of a solar panel made of perovskite crystals as a fancy slab of glass: light hits the crystal surface and gets absorbed, exciting electrons in the material. Those electrons travel easily through the crystal to electrical contacts on its underside, where they are collected in the form of electric current. Now imagine the sequence in reverse--power the slab with electricity, inject electrons, and release energy as light. A more efficient electricity-to-light conversion means perovskites could open new frontiers for energy-efficient LEDs.

Parallel work in the Sargent Group focuses on improving nano-engineered solar-absorbing particles called colloidal quantum dots. "Perovskites are great visible-light harvesters, and quantum dots are great for infrared," says Professor Sargent. "The materials are highly complementary in solar energy harvesting in view of the sun's broad visible and infrared power spectrum."

"In future, we will explore the opportunities for stacking together complementary absorbent materials," says Dr. Comin. "There are very promising prospects for combining perovskite work and quantum dot work for further boosting the efficiency."

RJ Taylor | EurekAlert!

More articles from Power and Electrical Engineering:

nachricht Failures in power grids: Dynamically induced cascades
25.05.2018 | Technische Universität Dresden

nachricht Beyond the limits of conventional electronics: stable organic molecular nanowires
24.05.2018 | Tokyo Institute of Technology

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>