%0 Journal Article
%A Liu, Fan
%A Yan, Ning
%A Zhu, Guangqi
%A Liu, Zigeng
%A Ma, Shenqian
%A Xiang, Guolei
%A Wang, Songrui
%A Liu, Xingjiang
%A Wang, Wei
%T Fe–N–C single-atom catalysts with an axial structure prepared by a new design and synthesis method for ORR
%J New journal of chemistry
%V 45
%N 29
%@ 0398-9836
%C London
%I RSC
%M FZJ-2021-05744
%P 13004 - 13014
%D 2021
%X Fe–N–C single-atom catalysts usually exhibit poor ORR activity due to their unsatisfactory O2 adsorption and activation. Here, a new design idea and tailored self-assembly synthesis method are reported to improve their ORR performance. DFT calculations indicate that the ORR electrocatalytic activity of Fe–N–C single-atom catalysts with an axial structure is superior to that of Fe–N–C single-atom catalysts with a Fe–N4 active site. In order to experimentally demonstrate the difference, Fe–N–C single-atom catalysts with a Fe–N5 active site were successfully synthesized on the surface of monolayer graphene. XANES, SEM, HRTEM, XRD, Raman and XPS analyses indicate that the synthesized Fe–N–C catalyst possessed nanofibre morphology and a curved layer-like crystal structure. For comparison, FePc powder was used as the FePc(Fe–N4) catalyst as its molecular structure involves a Fe–N4 active site embedded in carbon six-membered rings. The current density of the synthesized Fe–N5/C@G catalyst at a potential of 0.88 V vs. RHE is 1.65 mA cm−2, which is much higher than that of the FePc(Fe–N4) catalyst (1.04 mA cm−2) and even higher than that of commercial Pt/C catalyst (1.54 mA cm−2). The results are very well consistent with the DFT calculations, verifying the dependability and accuracy of DFT calculations. This work reports a new synthetic idea to obtain better performance and proposes a formation mechanism to explain the process of the synthesis method.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000669874900001
%R 10.1039/D1NJ01380G
%U https://juser.fz-juelich.de/record/904174