title: Controlled Growth of Nanostructured Biotemplates with Cobalt and Nitrogen Codoping as a Binderless Lithium-Ion Battery Anode.
abstract: Biomass can serve as a sustainable template for the synthesis of carbon materials but is limited by the intrinsic properties of the precursor organism. In this study we demonstrate that the properties of a fungal biotemplate can be tuned during cultivation, establishing a new electrode manufacturing process and ultimately improving the electrochemical performance of the biomass-derived electrode. More specifically, the carbon/nitrogen ratio of Neurospora crassa mycelia mats was shifted by 5-fold while generating cobalt nanoparticles into the hyphal structure originating from macroconidia spores. This shift was achieved through nitrate limitation and equal molar concentrations of Mg2+and Co2+in the growth media. The resulting mycelia mat was converted via a high-temperature pyrolysis process (800 °C) to produce a freestanding cobalt and nitrogen codoped electrode material with no postmodification. Ultimately, nitrogen doping resulted in one of the highest recorded specific reversible capacity for a freestanding biomass-derived lithium-ion anode (400 mAh g-1at C/10). We observed an additional improvement in capacity to 425 mAh g-1with the incorporation of 3 wt % Co. Our results show how shaping the chemical characteristics of an electrode during the growth of the biotemplate allows for sustainable carbon-based material manufacturing from a living (self-assembled) material.
authors.forename: Tyler M
authors.initials: TM
authors.lastname: Huggins
authors.forename: Justin M
authors.initials: JM
authors.lastname: Whiteley
authors.affiliation: Chemistry Department, U.S. Naval Research Laboratory , Washington, District of Columbia 20375, United States.
authors.forename: Corey T
authors.initials: CT
authors.lastname: Love
authors.affiliation: Department of Biology, Rutgers University , Camden, New Jersey 08102, United States.
authors.forename: Kwangwon
authors.initials: K
authors.lastname: Lee
authors.forename: Se-Hee
authors.initials: SH
authors.lastname: Lee
authors.forename: Zhiyong Jason
authors.initials: ZJ
authors.lastname: Ren
authors.affiliation: Chemistry Department, U.S. Naval Research Laboratory , Washington, District of Columbia 20375, United States.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Biffinger
keywords: biotemplate; cobalt; filamentous fungi; lithium; nitrate