One of most important part of the basic chemical industry and chemical process in the world is ‘catalytic reaction.’ If a reaction is too slow or produces too much byproduct, the reaction lacks industrial applicability. Therefore, it is critical to increase the activity and selectivity of catalytic reactions to enhance the reaction and production in various processes. This means that the reaction should be activated quickly and the production of byproduct should be prevented as much as possible. Nanotechnology, on which Professor Jung’s group is now focusing, is probably the most efficient regulatory mechanism of catalytic reactions.
“We can easily regulate catalytic reactions by using nanoparticles. We can prepare metal nanoparticles by placing metal precursors on a carbon substrate and apply a very high current for about one second. This is called carbothermal shock (CTS). The problem is that the particles prepared this way have a very low density.” Put simply, we know how to prepare the nanoparticles, but the key is to increase the density.

|Developing Economically Feasible Platform for Nanoparticle Preparation|

Formation of high-density nanoparticles by applying cellulose
Professor Jung’ s group first focused on the finding that the particle density is easier to control when the surface of the substrate for preparing metal nanoparticles has a multi-defect structure. So, the researchers chose, not a carbon-based substance, but cellulose, which is a kind of carbon precursor. Since cellulose can form much more defects on the substrate surface than previously reported materials, it can be used to prepare high-density nanoparticles.
The idea of the research group was demonstrated by an experiment. They coated a sheet of conductive carbon paper with cellulose, placed metal precursors, and applied a high current of 1 A for 1.5 second. As a result, they prepared metal nanoparticles having a density of 80% or higher. In addition, they found that high-density nanoparticles were prepared in all the experiments whether the metal precursors were of noble metal or not, and regardless of the number of the precursors. The platform, developed by combining CTS and cellulose, can be applied to realize a carbon dioxide conversion process, which used to fail due to the low particle density (30%). The research group actually realized the process and successfully produced ethylene, a high value-added product, from carbon hydroxide.

Abundant potentials for industrial application
The high-density metal nanoparticle synthesis method developed by the research group by using cellulose can be applied to various types of metal to prepare novel high-density nanoparticles. In addition, the short synthesis time and the use of cellulose that is rich on the earth provide the process with high economic feasibility. “Our technology may be applied more extensively to various applications in pursuit of carbon neutrality, including conversion of carbon hydroxide and nitrogen, energy storage systems, and secondary batteries. However, it is difficult to specify the industrial application at the moment, because we cannot predict the potentials that our platform has. It may be because the study is still in the early stage, but we can say for sure that our technology has tremendous potentials.”

Prof.Hee Tae Jung
2021 Annual Report