And when perfected, this approach might also cook up the solar cells in a microwave oven similar to the one in most kitchens.
These nanoparticles of copper zinc tin sulfide are processed with a common antifreeze solvent to produce good quality solar cells. (Image courtesy of Oregon State University)
Engineers at Oregon State University have determined that ethylene glycol, commonly used in antifreeze products, can be a low-cost solvent that functions well in a “continuous flow” reactor – an approach to making thin-film solar cells that is easily scaled up for mass production at industrial levels.
The research, just published in Material Letters, a professional journal, also concluded this approach will work with CZTS, or copper zinc tin sulfide, a compound of significant interest for solar cells due to its excellent optical properties and the fact these materials are cheap and environmentally benign.
“The global use of solar energy may be held back if the materials we use to produce solar cells are too expensive or require the use of toxic chemicals in production,” said Greg Herman, an associate professor in the OSU School of Chemical, Biological and Environmental Engineering. “We need technologies that use abundant, inexpensive materials, preferably ones that can be mined in the U.S. This process offers that.”
By contrast, many solar cells today are made with CIGS, or copper indium gallium diselenide. Indium is comparatively rare and costly, and mostly produced in China. Last year, the prices of indium and gallium used in CIGS solar cells were about 275 times higher than the zinc used in CZTS cells.
The technology being developed at OSU uses ethylene glycol in meso-fluidic reactors that can offer precise control of temperature, reaction time, and mass transport to yield better crystalline quality and high uniformity of the nanoparticles that comprise the solar cell – all factors which improve quality control and performance.
This approach is also faster – many companies still use “batch mode” synthesis to produce CIGS nanoparticles, a process that can ultimately take up to a full day, compared to about half an hour with a continuous flow reactor. The additional speed of such reactors will further reduce final costs.
“For large-scale industrial production, all of these factors – cost of materials, speed, quality control – can translate into money,” Herman said. “The approach we’re using should provide high-quality solar cells at a lower cost.”
The performance of CZTS cells right now is lower than that of CIGS, researchers say, but with further research on the use of dopants and additional optimization it should be possible to create solar cell efficiency that is comparable.
This project is one result of work through the Center for Sustainable Materials Chemistry, a collaborative effort of OSU and five other academic institutions, supported by the National Science Foundation. Funding was provided by Sharp Laboratories of America. The goal is to develop materials and products that are safe, affordable and avoid the use of toxic chemicals or expensive compounds.
The study this story is based on is available in ScholarsArchive@OSU; http://bit.ly/10Zj0SK
About the OSU College of Engineering: The OSU College of Engineering is among the nation¹s largest and most productive engineering programs. Since 1999, the college has more than tripled its research expenditures to $37.2 million by emphasizing highly collaborative research that solves global problems, spins out new companies, and produces opportunity for students through hands-on learning.
Greg Herman | EurekAlert!
Barely scratching the surface: A new way to make robust membranes
13.12.2018 | DOE/Argonne National Laboratory
Topological material switched off and on for the first time
11.12.2018 | ARC Centre of Excellence in Future Low-Energy Electronics Technologies
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
14.12.2018 | Power and Electrical Engineering
14.12.2018 | Physics and Astronomy
14.12.2018 | Physics and Astronomy