Ozhukil Valappil Manila, Ganguly Abhijit, Benson John, Pillai Vijayamohanan K, Alwarappan Subbiah, Papakonstantinou Pagona
Engineering Research Institute, School of Engineering, Ulster University Newtownabbey BT37 0QB UK
Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute Karaikudi Tamil Nadu 630003 India.
RSC Adv. 2020 Dec 9;10(71):43585-43591. doi: 10.1039/d0ra09763b. eCollection 2020 Nov 27.
We report the simple synthesis of bismuthene nanosheets (BiNS) by ionic liquid assisted grinding exfoliation, followed by size selection sequential centrifugation steps for the first time. The exfoliation process results in the formation of self-assembled spherule-like superstructures with abundant edge sites, which are able to catalyze the oxygen reduction reaction (ORR) a two-electron pathway, with a higher efficiency than the bulk Bismuth. We rationalize the enhanced ORR activity of the BiNS to: (i) the presence of 1 dimensional topological edge states, which provide strong conduction channels for electron hopping between the bismuth layers and (ii) the more active role of edge sites in facilitating O adsorption and dissociation of O-O bonds compared to the basal plane. The present study provides a pathway for employing 2D topological insulators as a new class of electrocatalysts for clean energy applications.
我们首次报道了通过离子液体辅助研磨剥离法简单合成铋烯纳米片（BiNS），随后进行尺寸选择顺序离心步骤。剥离过程导致形成具有丰富边缘位点的自组装球状超结构，这些超结构能够催化氧还原反应（ORR）——一条双电子途径，且效率高于块状铋。我们将BiNS增强的ORR活性归因于：（i）一维拓扑边缘态的存在，其为铋层之间的电子跳跃提供了强传导通道；（ii）与基面相比，边缘位点在促进O吸附和O - O键解离方面发挥了更积极的作用。本研究为将二维拓扑绝缘体用作清洁能源应用中的新型电催化剂提供了一条途径。
