@article {45636, title = {Graphene oxide sheathed ZIF-8 microcrystals: engineered precursors of nitrogen-doped porous carbon for efficient oxygen reduction reaction (ORR) electrocatalysis}, journal = {ACS Applied Materials \& Interfaces}, volume = {8}, year = {2016}, month = {NOV}, pages = {29373-29382}, type = {Article}, abstract = {

Nitrogen containing mesoporous carbon obtained by the pyrolysis of graphene oxide (GO) wrapped ZIF-8 (Zeolitic Imidazolate Frameworks-8) micro crystals is demonstrated to be an efficient catalyst for the oxygen reduction reaction (ORR). ZIF-8 synthesis in the presence of GO sheets helped to realize layers of graphene oxide over ZIF-8 microcrystals and the sphere-like structures thus obtained, on heat treatment, transformed to highly porous carbon with a nitrogen content of about 6.12\% and surface area of 502 m(2)/g. These catalysts with a typical micromeso porous architecture exhibited an onset potential of 0.88Vvs RHE in a four electron pathway and also demonstrated superior durability in alkaline medium compared to that of the commercial Pt/C catalyst. The N-doped porous carbon derived from GO sheathed ZIF-8 core shell structures could therefore be employed as an efficient electrocatalyst for fuel cell applications.

}, keywords = {alkaline fuel cell, graphene oxide, N-doped carbon, oxygen reduction reaction, porous carbon, ZIF-8}, issn = {1944-8244}, doi = {10.1021/acsami.6b06979}, author = {Thomas, Minju and Illathvalappi, Rajith and Kurungot, Sreekumar and Nair, Balagopal N. and Mohamed, Abdul Azeez Peer and Anilkumar, Gopinathan M. and Yamaguchi, Takeo and Hareesh, U. S.} } @article {44175, title = {Chitosan intercalated metal organic gel as a green precursor of fe entrenched and fe distributed N-doped mesoporous graphitic carbon for oxygen reduction reaction}, journal = {Chemistryselect}, volume = {2}, year = {2017}, month = {SEP}, pages = {8762-8770}, type = {Article}, abstract = {

Herein, we present Metal-Organic Gel intercalated with chitosan, a {\textquoteleft}green{\textquoteright}{\textquoteright} precursor for the synthesis of intrinsic N-doped Fe entrenched (CHI-TMA-Fe-CW) and Fe distributed mesoporous graphitic carbon structures (CHI-TMA-Fe-CW-M1) with appreciable Oxygen Reduction Reaction (ORR) activity in alkaline medium. Modulation of the synthetic protocol as a function of reaction kinetics and gelation time while maintaining identical pyrolysis conditions (900 degrees C, flowing N-2 atmosphere) improves the microstructure, surface area and Fe distribution of the graphitic structures (CHI-TMA-Fe-CW-M1). CHI-TMA-Fe-CW has a Fe entrenched graphitic nanocapsule like morphology while Fe distributed mesoporous graphitic carbon sheets, with a specific surface area value of 565 m(2) g(-1) obtained by modulating the synthesis chemistry in CHI-TMA-Fe-CW-M1. The higher percentage of graphitic N in CHI-TMA-Fe-CW-M1 apparent from the XPS data validate that the modified synthetic method favours creation of more graphitic N sites contributing for better catalytic performance. CHI-TMA-Fe-CW-M1 catalyst exhibited comparable electrocatalytic activity with that of the commercially available Pt/C via an efficient four-electron-dominant ORR pathway with a positive onset potential value of 0.925 V vs RHE. Good durability of CHI-TMA-Fe-CW-M1 after 5000 cycles further confirm the prospects of MOG-chitosan and the feasibility to be used as a potential catalyst for ORR.

}, keywords = {electrocatalyst, fuel cell, Metal-Organic-Gel, oxygen reduction reaction}, issn = {2365-6549}, doi = {10.1002/slct.201701416}, author = {Shijina, Kottarathil and Illathvalappil, Rajith and Kurungot, Sreekumar and Nair, Balagopal N. and Mohamed, A. Peer and Yamaguchi, Takeo and Anilkumar, Gopinathan M. and Hareesh, U. S. and Sailaja, G. S.} } @article {44637, title = {Morphological ensembles of N-doped porous carbon derived from ZIF-8/Fe-graphene nanocomposites: processing and electrocatalytic studies}, journal = {ChemistrySelect}, volume = {3}, year = {2018}, month = {AUG}, pages = {8688-8697}, abstract = {

Engineering the active site density of porous carbon catalysts for enhanced electrocatalytic activity is the current focus in the quest for economically viable fuel cells. Herein, we synthesise ZIF-8/Fe-graphene composites for the formation of N and Fe co-doped carbon with diverse morphologies ranging from tubes and sheets to frameworks of carbon. A synthetic strategy involving the one pot synthesis of ZIF-8 based composites is accomplished by the reaction of 2-methylimidazole with mixed Zn/Fe salt solution containing graphene dispersions. The high temperature heat treatment of this precursor mix yielded micro-meso porous architectures of N, Fe co-doped carbon with dispersions of Fe/Fe3C. An onset potential value of 0.95 V and a half-wave potential of 0.82 V coupled with excellent durability and stability in alkaline medium indicated improved electrocatalytic performances over its commercial Pt/C counterpart. The appreciable electrocatalytic properties of the synthesized carbon are attributed to its morphological diversity, hybrid structure, high N doping and its heteroporous characteristics. The dispersed Fe/Fe3C and FeNx sites facilitated enhanced oxygen adsorption and the graphene inclusions in the composite provided retention of high nitrogen contents.

}, keywords = {electrocatalyst, fuel cell, N- Fe co-doped carbon, oxygen reduction reaction, ZIF-8}, issn = {2365-6549}, doi = {10.1002/slct.201801419}, author = {Thomas, Minju and Illathvalappil, Rajith and Kurungot, Sreekumar and Nair, Balagopal N. and Mohamed, A. Peer and Anilkumar, Gopinathan M. and Yamaguchi, Takeo and Hareesh, U. S.} }