Nath Karabi, Bhunia Kousik, Pradhan Debabrata, Biradha Kumar
Department of Chemistry, Indian Institute of Technology Kharagpur-721302 India
Materials Science Centre, Indian Institute of Technology Kharagpur-721302 India.
Nanoscale Adv. 2019 Apr 16;1(6):2293-2302. doi: 10.1039/c9na00169g. eCollection 2019 Jun 11.
Development of cost-effective and efficient non noble metal electrocatalysts has immense importance towards sustainable energy technologies. Herein, a newly constructed porous Co(ii)-metal organic framework (MOF) has been utilized for the synthesis of cobalt nanoparticles embedded in N-doped porous carbon, (Co@NPC), a facile MOF-annealing strategy, at an optimum temperature of 800 °C under an argon atmosphere. DMF molecules present in the form of solvated guests and cations within the 3D-framework serve as a source for N-doping during the formation of the porous graphitic carbon upon carbonization. The nanocomposite was found to encapsulate homogeneously dispersed cobalt nanoparticles within the N-doped porous carbonaceous matrix. The synergistic effect of cobalt nanoparticles and the heteroatom-doped carbon framework makes Co@NPC electrochemically active towards both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) under alkaline conditions. Furthermore, Co@NPC exhibits outstanding performance as a bifunctional electrocatalyst towards electrochemical water splitting with remarkable stability and durability. It achieves a current density of 10 mA cm at a low cell voltage of 1.66 V in 1 M NaOH solution which is comparable with that of most of the self-templated ZIF-derived non-noble metal electrocatalysts.
开发具有成本效益且高效的非贵金属电催化剂对于可持续能源技术具有极其重要的意义。在此，一种新构建的多孔钴（II）金属有机框架（MOF）被用于合成嵌入氮掺杂多孔碳中的钴纳米颗粒（Co@NPC），这是一种简便的MOF退火策略，在氩气气氛下于800℃的最佳温度下进行。三维框架内以溶剂化客体和阳离子形式存在的DMF分子在碳化形成多孔石墨碳的过程中作为氮掺杂的来源。发现该纳米复合材料在氮掺杂多孔碳质基质中封装了均匀分散的钴纳米颗粒。钴纳米颗粒与杂原子掺杂碳框架的协同作用使Co@NPC在碱性条件下对析氧反应（OER）和析氢反应（HER）均具有电化学活性。此外，Co@NPC作为双功能电催化剂在电化学水分解方面表现出卓越的性能，具有出色的稳定性和耐久性。在1 M NaOH溶液中，它在1.66 V的低电池电压下实现了10 mA cm的电流密度，这与大多数自模板化ZIF衍生的非贵金属电催化剂相当。
