Nitrogen-doped hollow carbon spheres with highly graphitized mesoporous shell: Role of Fe for oxygen evolution reaction
•Fe and N-functionalized hollow carbon is prepared to investigate the role of Fe for OER.•Fe phthalocyanine was used as a single precursor for carbon, N, and Fe for doped carbon.•Presence of Fe leads to the efficient graphitization of N-dope carbon structure.•Nitrogen is undeniably needed for the efficient OER catalysis.•Fe is a must for the preparation of high efficient catalyst, but may not be necessary for OER.
There are many studies portraying iron (Fe) and nitrogen (N)-functionalzed carbon as an electrocatalyst along with possible elucidation of catalytically active sites. Despite continuous controversial debate on the active sites/species, the presence of N is believed to be undeniably needed for the efficient catalysis, whereas the necessity and role of Fe are still debated. To clearly understand the role of Fe in Fe and N-functionalized electrocatalyst, N-doped hollow mesoporous shell carbon (N-HMSC) is prepared as a uniform model electrocatalyst by a simple template nanocasting using Fe phthalocyanine (FePc) as a single precursor for carbon, N, and Fe. It is found that the presence of Fe in N-HMSC leads to the efficient graphitization of N-HMSC structure, which can be beneficial for electrocatalytic oxygen evolution reaction (OER). Interestingly, it is observed that Fe is a must for the preparation of high efficient catalyst, but may not be necessary for OER.
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Journal: Applied Catalysis B: Environmental - Volume 191, 15 August 2016, Pages 202–208