title: Catalyst-free synthesis of crumpled boron and nitrogen co-doped graphite layers with tunable bond structure for oxygen reduction reaction.
abstract: Two-dimensional materials based on ternary system of B, C and N are useful ranging from electric devices to catalysis. The bonding arrangement within these BCN nanosheets largely determines their electronic structure and thus chemical and (or) physical properties, yet it remains a challenge to manipulate their bond structures in a convenient and controlled manner. Recently, we developed a synthetic protocol for the synthesis of crumpled BCN nanosheets with tunable B and N bond structure using urea, boric acid and polyethylene glycol (PEG) as precursors. By carefully selecting the synthesis condition, we can tune the structure of BCN sheets from s-BCN with B and N bond together to h-BCN with B and N homogenously dispersed in BCN sheets. Detailed experiments suggest that the final bond structure of B and N in graphene depends on the preferentially doped N structure in BCN nanosheets. When N substituted the in-plane carbon atom with all its electrons configured into the π electron system of graphene, it facilitates the formation of h-BCN with B and N in separated state. On the contrary, when nitrogen substituted the edge-plane carbon with the nitrogen dopant surrounded with the lone electron pairs, it benefits for the formation of B-N structure. Specially, the compound riched with h-BCN shows excellent ORR performance in alkaline solution due to the synergistic effect between B and N, while s-BCN dominant BCN shows graphite-like activity for ORR, suggesting the intrinsic properties differences of BCN nanosheets with different dopants bond arrangement.
authors.affiliation: State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences , Lanzhou 730000, People's Republic of China.
authors.forename: Jutao
authors.initials: J
authors.lastname: Jin
authors.forename: Fuping
authors.initials: F
authors.lastname: Pan
authors.forename: Luhua
authors.initials: L
authors.lastname: Jiang
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Fu
authors.forename: Aiming
authors.initials: A
authors.lastname: Liang
authors.forename: Zhiyang
authors.initials: Z
authors.lastname: Wei
authors.forename: Junyan
authors.initials: J
authors.lastname: Zhang
authors.forename: Gongquan
authors.initials: G
authors.lastname: Sun