Category Technology/Electronics

An advance in the storage of concentrated solar thermal energy may reduce reduce its cost and make it more practical for wider use. Credit: Graphic by Kelvin Randhir, courtesy of the University of Florida

New approach for storage of concentrated solar thermal energy has been found, to reduce cost and make it more practical for wider use. The advance is based on thermochemical storage, in which chemical transformation is used in repeated cycles to hold heat, use it to drive turbines, and then be re-heated to continue the cycle. Most commonly this might be done over a 24 hour period, with variable levels of solar-powered electricity available at any time of day, as dictated by demand.

Conceptually, all of the energy produced could be stored indefinitely and used later when the electricity is...

This is a drawing of boron doped graphine. Credit: Torones, Penn State

An international team of researchers, led by Penn State, has developed ultrasensitive gas sensors based on the infusion of boron atoms into graphene. The researchers are from 6 countries and includes the 2010 Noble laureate and graphene pioneer Konstantin Novoselov, and Morinobu Endo, the discoverer of carbon nanotubes.

Graphene is well known for strength and ability to transport electrons at high speed, but it is also a highly sensitive gas sensor. By adding boron atoms, the boron graphene (BG) sensors were able to detect noxious gas molecules at extremely low concentrations, parts per billion in the case of nitrogen oxides and parts per million for ammonia, the two gases tested to date...

A high-quality mixed-organic-cation perovskite (MA)x(FA)1−xPbI3 is prepared from a phase-pure non-stoichiometric intermediate complex (FAI)1−x−PbI2. The phase-pure (FAI)1−x−PbI2 probably facilitates homogenous nucleation and modulates the growth kinetics during the crystallization of (MA)x(FA)1−xPbI3. This strategy can be expected to pave the way for the development of mixed-organic-cation perovskite solar cells.

NIMS researchers have developed the world’s first method to fabricate high-quality perovskite materials capable of utilizing long-wavelength sunlight of 800 nm or longer...

Optical absorption edge versus free electron density for the ZnSnN2 films. The calculated dependence of absorption on free electron density is also shown for the two extreme cases of cation ordered (blue dashed line) and fully cation disordered (red solid line) ZnSnN2. The calculations are performed using k·P band structures fitted to the DFT results close to the Γ point. The square points correspond to samples grown under less metal-rich conditions and triangular points to those grown under more metal-rich conditions.

University of Liverpool has demonstrated a new semiconductor material made from abundant elements which can be “tuned” for use in solar cells instead of rare elements...