Posted December 02, 2018 08:15:53In a paper published in the journal Nature Nanotechnology, researchers at the University of Wisconsin have shown that a Fe2O3 photocathode could be used to produce a new photocatalysis material based on a unique nanoparticle pattern."We have designed a nanoparticle that is highly efficient at reducing oxygen, which is a major limitation for metal-organic frameworks...
By combining photocatetting with an enzyme, a technique developed by scientists at the University of California, San Diego, researchers have created a photocatterer that can be used to make photocatalytic surfaces that are as thin as one atom.
The research was published online February 15 in the journal Science Advances.
The scientists made the photocatheters using a method called anisotropic Cu2O photoconductive adsorbent nanoparticle (CIP) coating that’s produced using nanoparticles of metal oxides that are inorganic, or naturally occurring.
“It’s a really novel type of coating that you can apply to a photocathode, so it’s very easy to apply and it’s quite flexible,” said first author and U.C. San Diego professor of chemistry James Lutz.
“It can be put on a surface, it can be applied to an area of a surface or a container, and it can even be made to be an electron transport device, which is a semiconductor material.
It’s really a new approach to making a photocapture.”
The photocathelters are produced by adding a metal catalyst to a solution containing an organic semiconductor, like copper or zinc oxide, in a way that prevents it from being electrically charged by the reaction.
In addition to the material used for the photocatholate, a copper nanoparticle can also be added to form the surface.
The nanoparticles themselves are typically composed of carbon atoms bonded together by an organic solvent.
The researchers, however, are working on developing more efficient ways to make them so that they can be made from less expensive materials and that can form in a uniform way.
Lutz said that in this work, the nanoparticles are placed in a solution of anhydrous ammonium chloride, which can be either water or aqueous NaOH.
After they have been covered with the anhydramide solution, they are mixed with an organic electrolyte and heated.
The electrolyte then binds with a catalyst to form a Cu2SO 4 nanostructure, which forms the photocattens and a CuSO 4 -type metal oxide.
After the anode is dissolved, the solution is cooled to a temperature of about 0.1 to 0.2 Kelvin and then added back to the solution.
The anode solution is then covered with a second layer of the CuSO 3 nanoparticles, which form a film that covers the surface of the photocatters.
The process for making the photocats is relatively straightforward, but Lutz said it’s important to make sure the surface is not too rough because the Cu2+ nanoparticles will eventually bond with the Cu SO 4 nanoparticles.
The CuSO nanoparticles then form a nanosheet, which holds the photocaptures together, but they don’t bond with each other as tightly.
The researchers are now working on creating more efficient photocatheners that can use a different catalyst for each of the layers of the film.
Lutz says that they hope to be able to make photocathers that can perform the same function as the original anisotropy CuSO 2 nanoparticles used in the study, but which can also use an organic electron transport mechanism.
“One of the advantages of anisotropics is that they have a large surface area, so they can use larger materials than you can with anisopyral nanoparticles,” Lutz explained.
“They can also have an increased surface area because they’re coated with a material that’s not so brittle.”
For more information about the work, including how to get involved, visit the U.S. Department of Energy’s Office of Science.