Scientists at the University of Basel have been able to gain success in identifying a silver catalyst at performance for the very first time with the assistance of an atomic force microscope. The observations obtained during an Ullmann reaction have enabled the experts to estimate the turnover of energy and deliberately to optimize the catalysis. The research explained that was performed with experts from Iran and Japan, has been published in a reputed scientific journal.
The examination of Ullmann reaction is a chemical reaction where the silver atoms catalyse the link between two carbon based atoms where in iodine was bonded in the past. Although researchers were aware about such form of reaction as a study was carried in 1901 and utilized it numerous vital chemical conversions, it was not conventionally possible to identify the intermediate product of the reaction in detail.
With use of an atomic force microscope, the panel of scientists headed by Lecturer Ernst Meyer and Dr. Shigeki Kawai belonging to the Swiss Nanoscience Institute and the Department of Physics at the University of Basel has now gained success in displaying such reaction at atomic resolution.
Figure 1: Ullmann Reaction with the silver catalyst (silver) between the carbon rings (black) and sulfur atoms (yellow) curves
Surprisingly, it was disclosed that the silver atoms reacted with the molecules at temperatures of approximately -120 Degree Celsius and appear to curve like a bridge over a river. In the later stage of the reaction that needs the temperature to be enhanced to around 105 Degree Celsius and releases the end product, the silver atoms are liberated again and two carbon based atoms link together.
The Ullmann reaction has been utilized for synthesis of chemical reaction for an extremely long time now. But conventional analysis failed to reveal the spatial assortment of the organometallic in-between product. The detailed pictures now secured are the foremost to enable project partner Lecturer Stefan Goedecker from Department of Physics and University of Basel to estimate the energy turnover of the analysis carried by Ullmann reaction. This information confirms the unusual spatial arrangement of the in-between products and confirms how the reaction can be optimized.
The observation curving and flexibility of the molecules is possibly the reason why the reaction needs deliberately low temperatures of 105 Degree Celsius. The molecules are constrained to perform mechanical tension, and hence, can react more conveniently, that is at a reduced temperatures. If other catalysts could be utilized to release intermediate products such as those that are subject to tension, then the catalytic reactions are possible to be conducted at lower temperatures.
Conclusion – It would make economic and ecological sense because conventional catalysts with palladium, rhodium and platinum often need high operating temperatures of approximately 500 Degree Celsius that results in the release of waste gases in a cold form.
Filed Under: News