Electronic and adsorption properties of the zigzag‐edged triangle graphene nanosheets

Abstract

The electronic and adsorption properties of the zigzag-edged triangle graphene nanosheets with different size are investigated, including the calculation of the adsorption energy, sensitivity and recovery time after adsorbing CO 2 , NO 2 , CH 4 and CO. The results show that the quantum size effect is satisfied in the triangle graphene nanosheets, and its conductivity type can be changed from p to n. In addition, the triangle graphene nanosheets with n = 5 has the highest sensitivity to NO 2 (374.79%), which is more than 300 times as compared to the lowest one. The recovery time of triangle graphene nanosheets with n = 4 is the shortest, and its sensitivity and recovery time are the best at 144 K. These results reveal that the zigzag-edged triangular graphene nanosheets can serve as the fundamental structural unit for the design of high sensitivity gas sensors.

On electron propagation in triangular graphene quantum dots

“…Considering only the nearest neighbour coupling, the two-component armchair wave functions [53, equation (48)] become the current (renormalized) armchair determinant sign homomorphism wave functions (113) that are discretized separately on the sublattices A + M and A − M . Even though properties of the triangular zigzag graphene quantum dots that are identical with the currently analysed shape have been recently studied [43,44], the majority of theoretical and experimental research has been conducted on the triangular zigzag dots which do not include the three corner positions [2,15,16,24,55,56,61] and which admit the nearest-neighbour coupling zero-energy states [51]. Precise relations between the electron wave functions and energy spectra inherent in these two slightly different types of the triangular zigzag graphene quantum dots deserve further study.…”

“…The matrix elements of the armchair hopping operators are for any points a, a ∈ H σ A,M defined utilizing the discrete ε-function (11), χ-function (15) and armchair coupling sets (24) as…”

“…The electron propagation in the zigzag graphene dots G σ Z,M surrounded by the boundary walls is up to the next-to-nearest neighbour couplings described by three zigzag hopping operators I σ, (k) Z,M : H σ Z,M → H σ Z,M , k ∈ {0, 1, 2}. The matrix elements of the zigzag hopping operators are for any points a, a ∈ H σ Z,M defined using the χ-function (15) and zigzag coupling sets (35) as…”

Role of External Electric Field in Carrier Mobility of Graphene/ZnO Heterojunction Adsorbed H2O and O2 Molecules

“…Two-dimensional (2D) materials with atomic-level thickness have attracted significant attention due to the unique physical properties including large specific surface area, non-zero band gap and high mobility, resulting in potential applications in nanoscale electronics, photonic and gas sensors devices. [1][2][3] Zinc oxide monolayer (ZnOÀ ML) is a novel 2D semiconductor material with wide band gap. It can be used in photodetectors because of its unique properties.…”