title: van Hove Singularity Enhanced Photochemical Reactivity of Twisted Bilayer Graphene.
abstract: Twisted bilayer graphene (tBLG) exhibits van Hove singularities (VHSs) in the density of states that can be tuned by changing the twist angle (θ), sparking various novel physical phenomena. Much effort has been devoted to investigate the θ-dependent physical properties of tBLG. Yet, the chemical properties of tBLG with VHSs, especially the chemical reactivity, remain unexplored. Here we report the first systematic study on the chemistry of tBLG through the photochemical reaction between graphene and benzoyl peroxide. Twisted bilayer graphene exhibits θ-dependent reactivity, and remarkably enhanced reactivity is obtained when the energy of incident laser matches with the energy interval of the VHSs of tBLG. This work provides an insight on the chemistry of tBLG, and the successful enhancement of chemical reactivity derived from VHS is highly beneficial for the controllable chemical modification of tBLG as well as the development of tBLG based devices.
authors.affiliation: †Center for Nanochemistry, Beijing Science and Engineering Centre for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liao
authors.affiliation: †Center for Nanochemistry, Beijing Science and Engineering Centre for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.affiliation: ‡Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K.
authors.forename: Han
authors.initials: H
authors.lastname: Peng
authors.affiliation: †Center for Nanochemistry, Beijing Science and Engineering Centre for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Yin
authors.affiliation: §Stanford Nano Shared Facilities, Stanford University, Stanford, California 94305, United States.
authors.forename: Ai Leen
authors.initials: AL
authors.lastname: Koh
authors.affiliation: ‡Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K.
authors.forename: Yulin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: †Center for Nanochemistry, Beijing Science and Engineering Centre for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Xie
authors.affiliation: †Center for Nanochemistry, Beijing Science and Engineering Centre for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Hailin
authors.initials: H
authors.lastname: Peng
authors.affiliation: †Center for Nanochemistry, Beijing Science and Engineering Centre for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Zhongfan
authors.initials: Z
authors.lastname: Liu
keywords: chemical modification; enhanced photochemical reactivity; twisted bilayer graphene; van Hove singularity