Study On The Electronic Transport Properties Of Two-dimensional Nanomaterials Based On Borophene

With the rapid development of information technology,the performance requirements of electronic devices on materials are becoming higher and higher.The appearance of two-dimensional nanomaterials has responded to the requirements of the times,so it has attracted a lot of attention.They exhibit rich physical and chemical properties,so they can be used in a wide range,and people have placed great hopes on them.Borophene,as a rising star of two-dimensional nanomaterials,soon became an important member of two-dimensional nanomaterials,and researchers'research on their properties has also become an important branch of materials science.The kind of borophene is quite abundant.In addition to several intrinsic borophene,more borophene-based derivatives have been found experimentally or theoretically.These derivatives enrich the performance of borophene and two-dimensional nanomaterials.1.We investigate the electronic transport properties of two-dimensional fully-hydrogenated borophene.Two-dimensional fully-hydrogenated borophene shows a perfect electrical transport anisotropy and is promising for applications.Along the peak-or equivalently the valley-parallel direction,it exhibits a metallic characteristic and its current-voltage curve shows a linear behavior,corresponding to the ON state in borophane-based nano-switches.In this circumstance,electrons mainly propagate via the B-B bonds along the linear boron chains.In contrast,electron transmission is almost forbidden along the perpendicular buckled direction(i.e.,the OFF state).Our research demonstrates that two-dimensional fully-hydrogenated borophene could combine metal and semiconductor features and may be a promising candidate for nano-switching materials with a stable structure and high ON/OFF ratio.2.We study the electronic transport properties along the zigzag(z-Zr B₂)and armchair(a-Zr B₂)directions of two-dimensional metal-diboride Zr B₂monolayers.Under low biases,the Zr B₂shows a similar electrical transport along zigzag and armchair directions as electric current propagates mostly via the metallic Zr-Zr bonds.However,it shows an electrical anisotropy under high biases,and its I-V curves along zigzag and armchair directions diverge as the bias voltage is higher than 1.4 V,as more directional B-B transmission channels are opened.In particular,both z-Zr B₂and a-Zr B₂show a negative differential conductance(NDC)effect and hence they can be promising for the use in NDC-based nanodevices.3.We have explored the electronic transport properties of two-dimensional h-B₂O monolayer.The current-voltage curves show the strong anisotropy of h-B₂O in electron transport behavior.The current is significantly larger in the zigzag direction(z-B₂O)than in the armchair one(a-B₂O).As the bias increases,the conductance of z-B₂O remains constant,but that of the a-B₂O begins to decrease when the bias is greater than 0.6 V.The effect of defects on z-B₂O are further studied.The result demonstrate that the current-voltage curve remains linear relationships when there is a boron or oxygen atom defect,and only the value of the current is changed.4.We study the electronic transport behavior of two-dimensional Al B₆monolayer.The current-voltage curve of a-Al B₆shows a C-L effect,but the current-voltage curve of z-Al B₆shows a linear relationship.Further analysis of its transmission pathway revealed that the transmission pathway exists in the aluminum atomic layer and the upper and lower boron atomic layers of z-Al B₆.But transmission pathway of a-Al B₆exists only in the upper and lower boron atomic layers.This reflects the electron transport anisotropy of Al B₆monolayer.The characteristics of Al B₆have potential application in nanodevices.