TU-TESL

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According to foreign media reports, the international research team has synthesized one-dimensional string platinum nickel alloy nanocomposites with platinum skin structure, which are used as catalysts for medium oxygen reduction reaction. The mass activity of the nano cage catalyst is as high as 3.52 amps per milligram of platinum, and the specific activity is also very high, reaching 5.16 amps per square centimeter of platinum, almost 17 times and 14 times as much as that of commercial platinum carbon catalyst, respectively. After 50000 cycles, the catalyst showed high stability and almost no activity degradation. Experimental results and theoretical calculations show that strain and ligand effect lead to less strongly bonded platinum oxygen sites. Supported by the catalyst, the current density of the fuel cell can reach 1.5a/cm2 at 0.6V, and it can run stably for at least 180 hours. Platinum is the most active electrocatalyst for oxygen reduction reaction in fuel cell and metal air. However, in terms of cost and large-scale commercial application, the activity and stability of even the most advanced platinum catalyst are still insufficient. Using the near surface structure of nano platinum alloy to improve the electrocatalytic performance of platinum based electrocatalyst, this method is very promising, which can find the most active sites with the best performance. "By adding other transition metals and adjusting the binding strength of platinum oxygen intermediates through ligand and strain effects, the catalyst performance can be improved," the researchers said. The introduction of open nanostructures such as hollow and porous nanoparticles, such as nanocapsules and nanostructures, will help to achieve this goal and improve mass transfer. " In order to prepare the nano cage, the research team first used a pot of solvothermal method to reduce the platinum and nickel precursors in different proportions, and prepared one-dimensional string platinum nickel alloy nano cage (BNSs). After being treated in acid condition, nickel species were selectively removed, leaving 1D Pt Ni BNCS, which was composed of platinum skin and residual platinum nickel alloy. "This study provides an effective strategy for the rational design of platinum alloy nanostructures, which will help guide the practical application of catalysts in energy conversion and other fields," the researchers said