Scientists have developed a new method of creating nanoporous materials with potential applications in everything from water purification to chemical sensors.
In order to produce a porous material it is necessary to have multiple components. When the minor component is removed, small pores are left in its place. Until now, creating nanoporous materials was limiting as it was believed the minor component had to be connected throughout the structure as well as to the outside in order for it to be removed.
However, new research published today (Sunday, 27 November) in the journal Nature Materials has demonstrated a much more effective, flexible method called collective osmotic shock (COS) for creating porous structures. The research, by scientists at the University of Cambridge, has shown how by using osmotic forces even structures with minor components entirely encapsulated in a matrix can be made porous (or nanoporous).
The lead author, Dr Easan Sivaniah from the University of Cambridge's Cavendish Laboratory, explains how the process works: "The experiment is rather similar to the classroom demonstration using a balloon containing salty water. How does one release the salt from the balloon? The answer is to put the balloon in a bath of fresh water. The salt can't leave the balloon but the water can enter, and it does so to reduce the saltiness in the balloon. As more water enters, the balloon swells, and eventually bursts, releasing the salt completely.
"In our experiments, we essentially show this works in materials with these trapped minor components, leading to a series of bursts that connect together and to the outside, releasing the trapped components and leaving an open porous material."
The researchers have also demonstrated how the nanoporous materials created by the unique process can be used to develop filters capable of removing very small dyes from water.
Dr Sivaniah added: "It is currently an efficient filter system that could be used in countries with poor access to fresh potable water, or to remove heavy metals and industrial waste products from ground water sources. Though, with development, we hope it can also be used in making sea-water drinkable using low-tech and low-power routes."
Other applications were explored in collaboration with groups having expertise in photonics (Dr Hernan Miguez, University of Sevilla) and optoelectronics (Professor Sir Richard Friend, Cavendish Laboratory). Light-emitting devices were demonstrated using titania electrodes templated from COS materials whilst the novel stack-like arrangement of materials provide uniquely efficient photonic multilayers with potential applications as sensors that change colour in response to absorbing trace amounts of chemicals, or for use in optical components.
Dr Sivaniah added, "We are currently exploring a number of applications, to include use in light-emitting devices, solar cells, electrodes for supercapacitors as well as fuels cells."For additional information please contact:
2. The work was funded by the Qatar Foundation (QNRF), EPSRC, CONACyT, and the Spanish Ministry of Science.
Easan Sivaniah | EurekAlert!
Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says
19.07.2018 | Purdue University
Machine-learning predicted a superhard and high-energy-density tungsten nitride
18.07.2018 | Science China Press
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
19.07.2018 | Earth Sciences
19.07.2018 | Power and Electrical Engineering
19.07.2018 | Materials Sciences