Table of Contents Table of Contents
Previous Page  12 / 54 Next Page
Show Menu
Previous Page 12 / 54 Next Page
Page Background

A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y 2 0 1 7

1 2




Researchers at the King Abdullah

University of Science and Technology

(KAUST), Saudi Arabia, developed a

new metal organic framework (MOF)

that can trap carbon dioxide at concen-

trations as low as 400 ppm—potentially

low enough to capture the gas as it is

generated. The gas adsorbtion and stor-

age capabilities of a specific MOF are

determined by the chemical compo-

sition and geometry of its major com-

ponents—metal ions or clusters held

in place by organic molecules known

as linkers. Square-shaped grid layers

composed of Ni(II) metal centers and

pyrazine linkers are bridged by pillars

composed of niobium, oxygen, and flu-

orine atoms.

“The ability to control the distance

between the fluorine atoms allows us to

create the ideal square-shaped pockets

for trapping carbon dioxide molecules

effectively and efficiently,” explains

Professor Mohamed Eddaoudi. The

MOF could be adapted to static indus-

trial processes, such as those used at

cement factories, but could also be

used on board vehicles to capture CO


at the point of emission—a significantly

more effective and efficient method

than removing it after it has mixed with

the atmosphere.




Researchers at the University of

Cambridge, UK, developed a prototype

of a next-generation lithium-sulfur bat-

tery that couldhave five times the energy

density of today’s lithium-ion batteries.

The design incorporates a chemically

functional layer inspired by the lining

of the human gut that drastically slows

the degradation of active material, over-

coming a key obstacle to the commercial

development of this type of battery.

When a Li-S battery discharges, the

lithium and sulfur interact to form chain-

likepolysulfides.Over several cycles, seg-

ments of these polysulfides can break off

and enter the electrolyte, decreasing the

available activematerial. The Cambridge


team’s functional layer lies on top of the

cathode to trap the detached active

material and fix it to a conductive frame-

work so it can be reused. Modeled after

villi—the fingerlike protrusions that line

the small intestine, increasing its surface

area and absorbing nutrients—themate-

rial consists of tiny, one-dimensional

zinc oxide nanowires grown on a scaf-

fold. It uses a lightweight carbon fiber

mat for support, which reduces overall

battery weight and, due to its flexibility,

allows the layer to mimic how the small

intestine works even further. Because of

the layer’s strong chemical bond with

the polysulfides, the active material

can be used for much longer, greatly

increasing the battery’s lifespan. “This

is the first time a chemically functional

layer with a well-organized nano-archi-

tecture has been proposed to trap and

reuse the dissolved active materials

during battery charging and discharg-

ing,” explains Ph.D. student Teng Zhao.


Solid MOF for carbon dioxide capture.

Courtesy of King Abdullah University.


Thermo-Calc Software AB,

Sweden, and

QuesTek International LLC,

Evanston, Ill., will establish a joint company,


Europe AB,

Sweden, to offer integrated computational materials engineering modeling services and novel materials design and

development in the European market. The new endeavor will combine the Materials by Design methodology developed in the U.S.

by QuesTek with the software and databases in the Thermo-Calc platform.,

Computer visualization of villi-like battery material. Courtesy of Teng Zhao.