Molecule to store solar energy developed

Date:
August 31, 2020
Source:
Linko"ping University
Summary:
Researchers have developed a molecule that absorbs energy from
sunlight and stores it in chemical bonds. A possible long-term use
of the molecule is to capture solar energy efficiently and store
it for later consumption.



FULL STORY ========================================================================== Researchers at Linko"ping University, Sweden, have developed a molecule
that absorbs energy from sunlight and stores it in chemical bonds. A
possible long- term use of the molecule is to capture solar energy
efficiently and store it for later consumption. The current results have
been published in the Journal of the American Chemical Society, JACS.


==========================================================================
The Earth receives many times more energy from the sun than we humans
can use.

This energy is absorbed by solar energy facilities, but one of the
challenges of solar energy is to store it efficiently, such that the
energy is available when the sun is not shining. This led scientists at Linko"ping University to investigate the possibility of capturing and
storing solar energy in a new molecule.

"Our molecule can take on two different forms: a parent form that can
absorb energy from sunlight, and an alternative form in which the
structure of the parent form has been changed and become much more
energy-rich, while remaining stable. This makes it possible to store
the energy in sunlight in the molecule efficiently," says Bo Durbeej,
professor of computational physics in the Department of Physics, Chemistry
and Biology at Linko"ping University, and leader of the study.

The molecule belongs to a group known as "molecular photoswitches." These
are always available in two different forms, isomers, that differ in
their chemical structures. The two forms have different properties, and
in the case of the molecule developed by LiU researchers, this difference
is in the energy content. The chemical structures of all photoswitches
are influenced by light energy. This means that the structure, and
thus the properties, of a photoswitch can be changed by illuminating
it. One possible area of application for photoswitches is molecular electronics, in which the two forms of the molecule have different
electrical conductivities. Another area is photopharmacology, in which
one form of the molecule is pharmacologically active and can bind to a
specific target protein in the body, while the other form is inactive.

It's common in research that experiments are done first and theoretical
work subsequently confirms the experimental results, but in this
case the procedure was reversed. Bo Durbeej and his group work in
theoretical chemistry, and conduct calculations and simulations of
chemical reactions. This involves advanced computer simulations, which
are performed on supercomputers at the National Supercomputer Centre, NSC,
in Linko"ping. The calculations showed that the molecule the researchers
had developed would undergo the chemical reaction they required, and
that it would take place extremely fast, within 200 femtoseconds. Their colleagues at the Research Centre for Natural Sciences in Hungary were
then able to build the molecule, and perform experiments that confirmed
the theoretical prediction.

In order to store large amounts of solar energy in the molecule, the researchers have attempted to make the energy difference between the
two isomers as large as possible. The parent form of their molecule is extremely stable, a property that within organic chemistry is denoted
by saying that the molecule is "aromatic." The basic molecule consists
of three rings, each of which is aromatic. When it absorbs light,
however, the aromaticity is lost, such that the molecule becomes much
more energy-rich. The LiU researchers show in their study, published
in the Journal of the American Chemical Society, that the concept of
switching between aromatic and non-aromatic states of a molecule has a
major potential in the field of molecular photoswitches.

"Most chemical reactions start in a condition where a molecule has
high energy and subsequently passes to one with a low energy. Here,
we do the opposite -- a molecule that has low energy becomes one with
high energy. We would expect this to be difficult, but we have shown
that it is possible for such a reaction to take place both rapidly and efficiently," says Bo Durbeej.

The researchers will now examine how the stored energy can be released
from the energy-rich form of the molecule in the best way.


========================================================================== Story Source: Materials provided by Linko"ping_University. Original
written by Karin So"derlund Leifler. Note: Content may be edited for
style and length.


========================================================================== Journal Reference:
1. Baswanth Oruganti, Pe'ter Pa'l Kalapos, Varada Bhargav, Ga'bor
London, Bo
Durbeej. Photoinduced Changes in Aromaticity Facilitate
Electrocyclization of Dithienylbenzene Switches. Journal of
the American Chemical Society, 2020; 142 (32): 13941 DOI:
10.1021/jacs.0c06327 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/08/200831124204.htm

--- up 1 week, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)