Development of novel advanced carbon materials is playing a critical role in the innovation of electrochemical energy storage technology. Hierarchical porous spore carbon produced by Aspergillus oryzae is reported, which acts as a biofactory. Interestingly, the spore carbon not only shows a porous maze structure consisting of crosslinked nanofolds, but also is intrinsically N and P dual doped. Impressively, the spore carbon can be further embedded with Ni2 P nanoparticles, which serve as porogen to form a highly porous spore carbon/Ni2 P composite with increased surface area and enhanced electrical conductivity. To explore the potential application in lithium-sulfur batteries (LSBs), the spore carbon/Ni2 P composite is combined with sulfur, forming a composite cathode, which exhibits a high initial capacity of 1347.5 mAh g-1 at 0.1 C, enhanced cycling stability (73.5% after 500 cycles), and better rate performance than the spore carbon/S and artificial hollow carbon sphere/S counterparts. The synergistic effect on suppressing the shuttle effect of intermediate polysulfides is responsible for the excellent LSBs performance with the aid of a physical blocking effect arising from the electrical maze porous structure and the chemical adsorption effect originating from N, P dual doping and polarized compound Ni2 P.
Keywords: Aspergillus oryzae spores; Li-S batteries; cathode; nickel phosphide; spore carbon.
© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.