Dye-sensitized solar cell technology was invented by Ecole Polytechnique Fédérale de Lausanne (EPFL) professor Michael Grätzel at EPFL in the 1990s and always seemed to have great promise as a cheap alternative to expensive silicon solar cells.
Dye-sensitized cells imitate the way that plants and certain algae convert sunlight into energy. The cells are made up of a porous film of tiny (nanometer-sized) white pigment particles made from titanium dioxide. The latter are covered with a layer of dye which is in contact with an electrolyte solution. When solar radiation hits the dye it injects a negative charge in the pigment nanoparticle and a positive charge into the electrolyte resulting in the conversion of sunlight into electrical energy.
The cells are inexpensive, easy to produce and can withstand long exposure to light and heat compared with traditional silicon-based solar cells but even state-of-the-art dye-sensitized cells only have an overall light conversion efficiency greater than 11%, about half that of silicon cell technology.
Another major drawback to dye-sensitized cell technology is the use of an electrolyte solution which is made up of volatile organic solvents and must be carefully sealed. This, along with the fact that the solvents permeate plastics, has precluded large-scale outdoor application and integration into flexible structures.
But now Grätzel, Shaik Zakeeruddin and colleagues from the Changchun Institute of Applied Chemistry at the Chinese Academy of Sciences have achieved a record light conversion efficiency of 8.2% in solvent-free dye-sensitized solar cells.
While still well behind silicon cells, this breakthrough in efficiency without the use of volatile organic solvents will make it possible to pursue large scale, outdoor practical application of lightweight, inexpensive, flexible dye-sensitized solar films that are stable over long periods of light and heat exposure.
To overcome the limitations expressed above, Grätzel and his colleagues developed a mixture of three solid salts as an alternative to using organic solvents as an electrolyte solution. When the three solid components are mixed together in the right proportion they turn into a melt showing excellent stability and efficiency.
Grätzel is confident that further development of these types of electrolyte mixtures will lead to large-scale practical application of dye-sensitized solar cell technology, reinforcing solar energy's role as a cornerstone of alternative energy production.
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Why An Extra Planet Can't Be Hidden Behind The Sun Or Above The South Pole
- My Applied National Security Paper. Being President Isn't For Idiots.
- Why Has Organic Farming Flatlined?
- Hugh Hefner's Wife Was Not Poisoned By Breast Implants
- Top Scientists Chastise Greenpeace
- SYRINA: A Trojan Horse For Endocrine Disrupting Chemicals?
- The Daily Physics Problem - 5
- "I try this one... I am a bit rusty, so my solution can be dramatically wrong. Given that B is uniform..."
- "wow! with a name like Wilhelmina Pelegrina, she can't do no wrong. also,some of the problems in..."
- "This is the best you could do? Golden Rice is in the public domain - the lack of any corporate..."
- "Dylan, okay first TL:DR, the answer is that for anything of 10 km upwards, months or a year or..."
- "Some more citations to work into the text later on:Eric Christensen, director of the UA's Catalina..."
- Cancer As Modern Lifestyle Disease? Only If There Was Processed Food 2 Million Years Ago
- Blood Test for Alzheimer’s: Close Or Hype?
- The Flavor Enhancing Molecule in Roasted Garlic Powder
- Pediatricians Should Provide Sex Ed, But Many Don’t
- Calico Cats Are A Walking Genetics Lesson
- Statins Could Help Prevent Some Pregnancy Ills
- Opercular index score: A novel approach for determining clinical outcomes in stroke
- Cataclysm at Meteor Crater: Crystal sheds light on Earth, moon, Mars
- Workforce processes prior to mechanical thrombectomy vary widely, new study finds
- Male frogs have sex on land to keep competitors away
- Cord blood outperforms matched, unrelated donor in bone marrow transplant