Electronic and transport properties of porous graphene sheets and nanoribbons: benzo-CMPs and BN codoped derivatives

Abstract

†Electronic supplementary information (ESI) available: Schematic diagram of method shearing two dimensional porous graphene sheet into different kind of nanoribbons; PDOS of two-probe device of 3-Benzo-CMP, BN-3-Benzo-CMP and BN-p-3ZGNR(w=4) at 0.0 and 2.0 V bias voltage; I-V b curves of BN-p-3AGNR(w=2), BN-p-4AGNR(w=2), BN-p-5AGNR(w=2), BN-p-4ZGNR(w=4) and BN-p-5ZGNR(w=4).Abstract We investigate the electronic and electron transport properties of a series of 2D porous n-Benzo-CMPs (CMP refers to π-conjugated microporous polymers) sheets with different pore size n and their boron-nitride (BN) codoped derivatives, BN-n-Benzo-CMPs, as well as one-dimensional (1D) porous graphene nanoribbons (p-GNRs) tailored from n-Benzo-CMPs and BN-n-Benzo-CMPs using density-functional theory (DFT) and the non-equilibrium Green's function (NEGF) methods.We find that the n-Benzo-CMPs and BN-n-Benzo-CMPs (n = 3, 4, 5) sheets are all semiconductors with direct band gaps (0.57 -1.75 eV). Their band gap decreases with increasing the pore size n. In addition, the 1D armchair and zigzag P-GNRs tailored from 2D n-Benzo-CMPs and BN-n-Benzo-CMPs (n = 3, 4, 5) sheets are all semiconductor with the band gaps ranging from 0.19 to 2.0 eV. BN codoping, pore size (n), and the width of nanoribbons (w) can all be used to tune the band gap of either 2D porous graphenes or their corresponding 1D p-GNRs. Computed current-voltage (I-V b ) curves are consistent with the semiconducting properties and suggest that both BN-3-Benzo-CMP and BN-p-3ZGNR (w = 4) can be exploited for applications in low-dimensional electronics.

First‐Principles Study on Methane Adsorption Performance of Ti‐Modified Porous Graphene

“…The unit cell was composed of three C 6 H 2 rings connected by C-C bonds, which can be regarded as three C 6 H 2 rings connected to a C 6 ring, and this structure is consistent with that described in a previous study. [40] The calculated bandgap of PG was 1.792 eV, which is consistent with the result (1.750 eV) calculated by Li et al [44] using SIESTA software. This implies that the selected calculation model is reasonable, the calculation method is appropriate, and the calculation result is reliable.…”

Metal-free C5N2 doped with a boron atom as an efficient electrocatalyst for the nitrogen reduction reaction

“…39,40 In computational studies, C 5 N 2 was demonstrated to be a a Institute of Functional Materials Chemistry, Key Laboratory of Polyoxometalate semiconductor with a direct bandgap of about 1.1 eV. 41,42 Besides, the well-ordered holes of the C 5 N 2 make it a promising support to anchor B atoms in vacancies. Similar to C 2 N and C 3 N 4 , the properties of C 5 N 2 may also be tuned by doping B.…”

Theory-Driven Design and Targeting Synthesis of a Highly-Conjugated Basal-Plane 2D Covalent Organic Framework for Metal-Free Electrocatalytic OER

“…It is well-known that Ndoping can adjust the energy band structure of graphene and graphene-like structures, thereby regulating its semiconductive properties. 38 Although N content and the doped position formed by self-assembly of condensation between monomers are designable in N-doped 2D-COFs, 39,40 the targeting synthesis of 2D-COFs driven by effective theory prediction for the specific electrocatalytic activity has not been known. In this work, on the basis of the analysis and comparison for references and our DFT calculations, we first designed a new phenazine-linked COF-C 4 N with distributed hexagonal pores and C 4 N stoichiometry and initially predicted the potential OER activity.…”

“…As shown in Figrue S1a, C 2 N-h2D (h-C 2 N) and Aza-CMP (h-C 5 N 2 ) were thought to be potential OER catalysts based on our group's previous work 38,40 because their hexagonal porous graphene-like structures are similar to those of N-doped graphenes with OER performance. 10−15 h-C 2 N and h-C 5 N 2 could be constructed by replacing each double bond in graphene with three or five fused phenazine-linked rings to exhibit graphene-like honeycomb structures.…”

“…J. O. Hoberg and co-workers reported highly conjugated COFs modified by different functional groups; however, its lower N ratio would limit the performance in electrocatalysis. It is well-known that N-doping can adjust the energy band structure of graphene and graphene-like structures, thereby regulating its semiconductive properties . Although N content and the doped position formed by self-assembly of condensation between monomers are designable in N-doped 2D-COFs, , the targeting synthesis of 2D-COFs driven by effective theory prediction for the specific electrocatalytic activity has not been known.…”