(Press-News.org) (Winston-Salem, N.C. - May 5, 2015) - Researchers from Wake Forest University and the University of Utah are the first to successfully fabricate halide organic-inorganic hybrid perovskite field-effect transistors and measure their electrical characteristics at room temperature.
"We designed the structure of these field-effect transistors that allowed us to achieve electrostatic gating of these materials and determine directly their electrical properties," said lead author, Oana Jurchescu, an assistant professor of physics at Wake Forest. "Then we fabricated these transistors with the Utah team and we measured them here in our lab."
Hybrid perovskites are a family of crystalline materials that hold great promise in the clean energy world.
Until now, researchers have not been able to fabricate field-effect transistors to measure the charge transport of the materials. Necessary prerequisites for a material that forms an efficient solar cell are strong optical absorption and efficient charge carrier transport, Jurchescu said. With these first generation transistors, the Wake Forest researchers were able for the first time to directly measure and calculate the electrical properties, eliminating indirect approximations.
"This is exciting because hybrid perovskites could be the next generation of solar cells," she said. "The solar cells convert solar energy into electrical energy so it's a sustainable and environmentally friendly energy source, giving high performance at a low cost."
Zeev "Valy" Vardeny, co-author and distinguished professor of physics and astronomy, University of Utah, agrees. "This work shows that in addition to solar cell technologies, the hybrid perovskites have potential to be used in a variety of optoelectronic applications."
This next step in the development of these materials as the possible next generation of solar cell components is detailed in a study published online in the journal MRS Communications by the two research teams.
Jurchescu said hybrid perovskites have taken the solar cell field by storm since 2009, when they were first introduced. The power conversion efficiencies have grown from around 4 percent to 20 percent in just five years. By comparison, other conventional materials used to generate electricity from sunlight have taken decades to achieve high performance levels.
Jurchescu and graduate student Yaochuan "Josh" Mei, who has worked in her lab for almost five years, said this research builds on what they have learned in their previous work. "This work is based on the knowledge and infrastructure learned from our organic electronics work over the years," Mei said. "This material is pretty new for us and we learned a lot in just a few months."
"We will learn from these first lessons and try to make them better," Jurchescu said. "Really, this is just the first step. Next we will look into the spin manipulation of the injected carriers in these devices and other electrical, optical and magnetic field applications."
INFORMATION:
Co-authors from the University of Utah are Z. Valentine Vardeny and C. Zhang.
About Wake Forest University
Wake Forest University combines the best traditions of a small liberal arts college with the resources of a large research university. Founded in 1834, the school is located in Winston-Salem, N.C. The University's graduate school of arts and sciences, divinity school, and nationally ranked schools of law, medicine and business enrich our intellectual environment. Learn more about Wake Forest University at http://www.wfu.edu.
This news release is available in German.
With the first detailed observations of a lava lake on a moon of Jupiter, the Large Binocular Telescope Observatory in Arizona places itself as the forerunner of the next generation of Extremely Large Telescopes. The applied high-resolution imaging methods were developed by an international research team including scientists from the Max Planck Institute for Radio Astronomy in Bonn and the Max Planck Institute for Astronomy in Heidelberg.
Io, the innermost of the four moons of Jupiter discovered by Galileo in January ...
This news release is available in German.
Overturning cars, flying missiles, and airplanes speeding across the screen -- on modern computers, 3D objects can be calculated in a flash. However, many surfaces still look unnatural. Whether it is skin, stone or wax -- on the computer screen, all materials look alike, as if the objects had all been cut out of the same kind of opaque material. This is about to change: TU Wien (Vienna), the University of Zaragoza and the video game company Activision-Blizzard have developed a new mathematical method which makes surfaces appear ...
Our view of what makes us happy has changed markedly since 1938.
That is the conclusion of the psychologist Sandie McHugh from the Univeristy of Bolton who has recreated a famous study of happiness conducted in Bolton in 1938. She will present her study today, Tuesday 5 May 2015, to the Annual Conference of the British Psychological Society in Liverpool.
In 1938 Mass Observation placed an advertisement in the the Bolton Evening News asking readers to answer the question 'What is happiness?'. A total of 226 people sent letters in reply, and they were asked to help compile ...
Ribosomes are vital to the function of all living cells. Using the genetic information from RNA, these large molecular complexes build proteins by linking amino acids together in a specific order. Scientists have known for more than half a century that these cellular machines are themselves made up of about 80 different proteins, called ribosomal proteins, along with several RNA molecules and that these components are added in a particular sequence to construct new ribosomes, but no one has known the mechanism that controls that process.
Now researchers from Caltech and ...
AUSTIN, Texas -- Researchers in the Cockrell School of Engineering at The University of Texas at Austin have developed a centimeter-accurate GPS-based positioning system that could revolutionize geolocation on virtual reality headsets, cellphones and other technologies, making global positioning and orientation far more precise than what is currently available on a mobile device.
The researchers' new system could allow unmanned aerial vehicles to deliver packages to a specific spot on a consumer's back porch, enable collision avoidance technologies on cars and allow virtual ...
SAN DIEGO, Calif. (May 5, 2015)-- Acceptance of premarital sex is at an all-time high along with an acceptance of homosexuality, find researchers led by Jean M. Twenge from San Diego State University.
The researchers -- also including Ryne Sherman from Florida Atlantic University and Brooke E. Wells from Hunter College -- analyzed data from the General Social Survey, a nationally representative survey of more than 33,000 U.S. adults taken between 1972 and 2012. They found substantial generational shifts in attitudes toward non-marital sex and number of sexual partners. ...
Using proteomics techniques to study injured optic nerves, researchers at Boston Children's Hospital have identified previously unrecognized proteins and pathways involved in nerve regeneration. Adding back one of these proteins--the oncogene c-myc--they achieved unprecedented optic nerve regeneration in mice when combined with two other known strategies. The findings were published online April 30 by the journal Neuron.
Researchers have been trying for many decades to get injured nerves in the brain and spinal cord to regenerate. Various molecules have been targeted ...
"Imagine a tiny spotlight like those used in theatres but with a light ray measuring only a few nanometres, which shines light on a given spot but leaves everything else in the dark," explains Monica Mazzolini, SISSA research scientist, "That's how the optic fibres we used in our experiment work". Mazzolini, first author of a paper just published in PNAS, literally shut herself in a "darkroom" lit with infrared light only to stimulate rods, the light-sensitive cells of the retina (for night vision), with these extremely focused light beams in vitro. In their study, Mazzolini ...
ARLINGTON HEIGHTS, Ill. (May 5, 2015) - While it may be a stereotype, it's also true that women seek medical care more frequently than men do. And a recent study shows that women with acute asthma who are treated in the emergency department (ED) are 60 percent more likely than men treated in the ED to need hospitalization.
The study, published in the Annals of Allergy, Asthma and Immunology, the scientific publication of the American College of Allergy, Asthma and Immunology (ACAAI), looked at the sex differences in patient characteristics, and risk of hospitalizations ...
DALLAS, May 4, 2015 -- More bystanders performing CPR contributed to more cardiac arrest survivors returning to work in a Danish study published in the American Heart Association journal Circulation.
In the largest study to date to examine return to work after cardiac arrest, researchers studied 4,354 patients in Denmark who were employed before they suffered out-of-hospital cardiac arrests between 2001 to 2011. Researchers found:
More than 75 percent of survivors who had a cardiac arrest outside a hospital were capable of returning to work.
Chances of returning ...
