Babatunde Okesola
(November 9, 2015) Research
by scientists at the University of York has demonstrated an innovative way of
using a gel to extract precious metals such as silver and gold from waste and
convert them into conducting nanoparticles to form a hybrid nanomaterial
potentially suitable for a range of high-tech applications.
Discarded electronic devices are an ever-increasing waste
stream containing high-value precious metals such as silver and gold. Making use of this resource was the
inspiration for the research by a team from the Department of Chemistry at
York.
Professor David Smith and Babatunde Okesola, a PhD student
supported by The Wild Fund, discovered that their self-assembling gels derived
from sorbitol, a simple sugar, could selectively extract precious metals from
complex mixtures of other metals typical of the electronics or mining
industries.
On exposure to the gel, not only were the precious metals
selectively extracted, but they were also then converted into conducting
nanoparticles via an in situ chemical reduction process, caused by the
nanofibres of the gel network. These
conducting nanoparticles become embedded in the gel giving it enhanced
electrical conductance.