Congratulation Li Bing and Hong Gi for Adv. MAt. acceptance!
Nice piece of expt and theory works!
Title: Nanoreactor of Nickel-Containing Carbon-Shells as Oxygen Reduction Catalyst
Author : Bing Li, Honggi Nam, Jiong Zhao, Jian Chang, Niranjanmurthi Lingappan, Fei Yao, Tae Hoon Lee and Young Hee Lee*
Abstract : Rareness and weak durability of Pt-based materials for oxygen reduction reaction (ORR) have hindered large-scale applications of fuel cells. We develop a Pt-free nanoreactor for high-performance ORR catalyst, consisting of N-doped hollow carbon nanocapsules with encapsulated Ni nanoparticles (Ni@N-CNCs). The nanoreactor effect improves its catalytic activity for ORR mainly in a 4e- pathway with a low HO2- yield of below 1.5%. The presence of Ni nanoparticles within the nanoreactor significantly enhances the stability with a current retention of 90% after 40 h. The nitrogen-functional groups play a key role in nucleating Ni nanoparticles so that Ni improves the chemical stability against oxidation, further supported by density functional calculations. Compared to commercial Pt/C catalyst, our nanoreactor catalyst exhibits similar catalytic activity but superior durability and methanol tolerancein alkaline medium, making it a good candidate for an ORR electrocatalyst in fuel cell applications.