 Nano Express
 Open Access
 Published:
Rectifying Performance of Heterojunction Based on αBorophene Nanoribbons with Edge Passivation
Nanoscale Research Letters volume 15, Article number: 185 (2020)
Abstract
We propose a planar model heterojunction based on αborophene nanoribbons and study its electronic transport properties. We respectively consider three types of heterojunctions. Each type consists of two zigzagedge αborophene nanoribbons (Z αBNR), one is metallic with unpassivated or passivated edges by a hydrogen atom (1HZ αBNR) and the other is semiconducting with the edge passivated by two hydrogen atoms (2HZ αBNR) or a single nitrogen atom (NZ αBNR). Using the firstprinciples calculations combined with the nonequilibrium Green’s function, we observe that the rectifying performance depends strongly on the atomic structural details of a junction. Specifically, the rectification ratio of the junction is almost unchanged when its left metallic ribbon changes from ZBNR to 1HZ αBNR. However, its ratio increases from 120 to 240 when the right semiconducting one varies from 2HZ αBNR to NZ αBNR. This rectification effect can be explained microscopically by the matching degree the electronic bands between two parts of a junction. Our findings imply that the borophenebased heterojunctions may have potential applications in rectification nanodevices.
Introduction
Over the past decades, a great number of twodimensional (2D) materials, including graphene [1, 2], silicene [3, 4], transition metal dichalcogenides (TMD) [5, 6], and phosphorene [7, 8], have been extensively studied due to their unique properties. Especially, these 2D materials demonstrate some interesting electronic transport behaviors, such as giant magneto resistance (GMR) [9, 10], negative differential resistance (NDR) [11, 12], spin filtering [13, 14], and rectification [15, 16], thus having potential applications in nanoscale electronic devices. Recently, some studies have also shown that 2D materials have broad application prospects in nanoscale thermoelectric devices [17–20]. Subsequently, the research on lateral heterojunctions based on 2D materials becomes an important topic. And some theoretical studies have showed that the lateral heterojunctions have potential applications in field effect transistor and complementary metal oxide semiconductor technologies [21, 22]. Further, the lateral heterojunctions with atomic thickness have already been prepared in experiments [23, 24]. These achievements have inspired the effort for further exploring lateral heterojunctions made of more suitable 2D materials.
Recently, borophene monolayers have also received extensive interests [25–28] after graphene and silicene. The theoretical studies predicted that the monolayer boron sheets can be stably existed on the metallic substrate, which was confirmed by the subsequent observations [29, 30]. So far, a number of 2D boron structures have been obtained by epitaxial growth on Ag (111) substrates, such as β_{12}, χ_{3}, δ_{6}borophene and honeycomb borophene [31–34]. Theoretical studies point out that the stability of the boron sheet can be increased by introducing a hexagonal hole [35]. The DFT calculations indicated that the borophene with a “hexagon hole density” (η) of 1/9, named as α−borophene [35, 36], is favorable in terms of energy. Further, the zigzag edge αborophene nanoribbon (Z αBNR) exhibits either metallic or semiconducting behavior through different edge modifications [37]. Hence, the electronic transport property for borophene nanostructures remains to be explored further, although a large number of studies have been carried out on the electronic structures, mechanical and thermal properties [25–28].
In this work, we investigate the transport properties of heterojunctions made of the zigzag edge Z αBNRs. We construct three types of inplane metalsemiconductor lateral junctions. We find that all the junctions exhibit rectification behavior in the low bias regime due to the presence of the interfaces in the scattering region and the asymmetry on the left and right sides. Moreover, the rectifying effect of the junctions becomes pronounced with the increase of primitive cell numbers in the semiconductor part of the junction. The transport properties of junctions strongly depended on right part semiconducting nanoribbons. This phenomenon can be ascribed to the band gap near the Fermi level of the semiconducting part. The probability of electrons through the junction to be smaller when the band gap is increasing, which causes the current of the junction decreased and the rectification ratio increased. In particular, the rectification rate of junction M10N can reach about 240, which is comparable to the previously studied heterojunction with graphene as an electrode and indicates that it has potential applications in rectification devices [38]. The organization of this paper is as follows. In the “Model and Computational Methods” section, we describe the computational details. In the “Results and Discussion” section, we present the transport properties of the proposed junctions. Finally, we summarize our results in the “Conclusions” section.
Model and Computational Methods
The unit cells of the considered Z αBNRs without or with outmost edgeapex modifications are shown in the upper part of Fig. 1, where (a) for the unpassivated Z αBNR, (b–d) for the Z αBNRs with the outmost edge boron atoms of the cell passivated by one hydrogen (H), two H atoms and replaced by a nitrogen (N) atom, which are named as 1HZ αBNR, 2HZ αBNR, and NZ αBNR, respectively. And their corresponding electronic energy dispersions are subsequently shown in the lower part of Fig. 1, from which we can identify the difference in band structure for the ribbons. From Fig. 1a, several bands of the intrinsic pristine Z αBNR crosses over the Fermi level (E_{F}), which exhibits metallic property. For 1HZ αBNR, since the partially dangling bonds are saturated with H atoms, the number of bands near the E_{F} are less than those for the unpassivated one and also exhibits metal behavior. For 2HZ αBNR, however, the E_{F} moves to the gap between the bonding and antibonding bands due to the dangling bonds at the edge are saturated with two H atoms. Therefore, 2HZ αBNR is a semiconductor with a 0.43 eV direct band gap at the Γpoint as shown in Fig. 1c. We mention that our results of band structure for Hpassivated ribbons here agree well with the previous numerical calculations [37]. Moreover, as shown in Fig. 1d, the band structure of NZ αBNR indicates that it is a semiconductor with a 1.0 eV indirect band gap. This may be owing to the substitution of N to the B atomic positions at the edge, which brings enough electrons to fill the bonding orbits.
We establish three metal/semiconductor lateral heterojunction models based on the above mentioned Z αBNRs. Each model junction is divided into three parts: the left electrode, the right electrode, and the central scattering region. The geometry structure of the junctions, as shown in Fig. 2, where the left electrode is always a semiinfinitive long bare unpassivated Z αBNR or 1H Z αBNR, and the right electrode is either a semiconducting 2H or NZ αBNR. Particularly, however, the central scattering regions of the three junctions are a Z αBNR unit cell coupled with n (n = 1, 2, 5, 8, 10) unit cells of 2HZ αBNR, a 1HZ αBNR coupled with n cells of 2HZ αBNR, and a Z αBNR cell coupled with n cells of NZ αBNR, respectively. Likewise, we accordingly name them as the MnH, M’nH and MnN junctions, which are shown in Fig. 2a–c, respectively. It is worth noting that Fig. 2 only shows a schematic diagram of the model with n = 1 and the other cases of n are omitted for saving the space.
The calculations were performed using the software package Atomistix ToolKit (ATK), QuantumWise A /S (www.quantumwise.com), which is based on the DFT combined with the Keldysh nonequilibrium Green’s function (NEGF) [39–41]. The PerdewBurkeErnzerhof (PBE) functional under the generalized gradient approximation (GGA) is used for the exchangecorrelation potential. The Borilliouin zone (BZ) is sampled by using a 1×1×100 MonkhorstPack kmesh, and the cutoff energy is set to 150 Ry. The geometric structures of all heterojunctions were relaxed until the absolute value of force acting on each atom is less than 0.01 eV Å ^{−1}. In order to avoid interactions between periodic images, the supercell at least has a vacuum layer thickness of 15 Å.
The current through the heterojunction under a bias voltage V is calculated by the LandauerBüttiker formula [42, 43]
where h, e, and V are respectively the Planck’s constant, the elementary charge, and the bias voltage, and f_{L/R}(E,V) is the FermiDirac distribution function in the left/right electrode. The transmission coefficient is calculated by
where G(E,V) and G^{†}(E,V) denote the retarded and advanced Green’s function, respectively, and Γ_{L} (Γ_{R}) is the coupling matrix between the central scattering region with the left (right) electrode.
Results and Discussion
The calculated current −voltage (I−V) curves of heterojunctions MnH, M ^{′}nH, and MnN within the bias range of −1.0 to 1.0 V are shown in Fig. 3a–c, respectively. From these I−V curves, we can clearly see that with the increment of positive bias, the current increases rapidly in all three types of junctions. However, with the increase of the negative bias, the current through the junctions are increased more slowly. The I−V curves have obviously asymmetric characteristics under the whole bias, which means that the junctions have a rectification behavior within the bias range. The rectification effect in the heterojunction is mainly caused by the asymmetry of the different nanoribbons on the left and right sides and the formation of the interface in the central scattering region. In order to evaluate the strength of the rectification behavior, we use the data for the I−V curves to calculate the rectification ratio (RR), which is defined as RR (V)= I(+V)/I(−V), where I(±V) represents the current under positive and negative bias. The calculated RRs of the three types of junctions MnH, M ^{′}nH, and MnN within the 0.1 V −0.5 V bias range are shown in Fig. 3d–f, respectively. For type MnH, the RR of M1H is only 3 at 0.2 V while that of M10H can reach 115 at the same bias. Similarly, for the M ^{′}nN type at bias 0.2 V, the RR of M ^{′}1H is 3 and that of M ^{′}10H is up to 90. Moreover, for the MnN type, the RR of M1N is 2 at 0.3 V while that of M10N reaches up to 240. Further, by careful observation on Fig. 3, we find that the magnitude of the current and RR can be controlled by changing the size of the semiconductor part of the junction. In specific, on the one hand, the current in the junction is reduced with the number of primitive cells of the semiconductor part is increased. On the other hand, the RR is significantly increased with the number of primitive cells is increased. Since the right side of the heterojunction is a semiconductor nanoribbon with a band gap, the probability of electron tunneling decays exponentially as the length of the semiconductor increases. As a result, in the heterojunctions of MnH, M ^{′}nH, and MnN, as n increases, RR increases significantly. This result is in good agreement with previous studies on the heterojunctions based on other 2D materials [44–46].
Comparing the I−V curves and RRs among the three types of heterojunctions shown in Fig. 3, we find that the variation of I−V curves and RRs for MnH and M ^{′}nH have the similar trends. However, those for MnN are significantly different. In order to explain the difference in transport properties of the three types of junctions, we have calculated the transmission spectra under zero bias shown in Fig. 4, where the band structures of the left and right electrode are accompanied. From these transmission spectra, one can see that all of the junctions have a transmission gap near the Fermi level, where we use the magenta dotted line to denote the gap position. The reason for the existence of the transmission gap is that the energy band structure of the right electrode has a gap near the Fermi level. Thus, the band structure of the left and right electrodes does not match, causing the transport channel to be closed, and the electrons of the left electrode cannot reach the right electrode. This is also the physical origin of the weak current at the low bias. Additionally, the comparison of Fig. 4a, b and Fig. 4a, c shown that the transmission spectra of MnH and M ^{′}nH under zero bias has similar trends; however, the trends of MnH and MnN are quite different. This is determined by the matching degree of the left and right electrodes band structures near the Fermi level. The left metallic nanoribbon of the junction M ^{′}nH changes from Z αBNR to 1HZ αBNR compared to MnH. The matching degree between left and right electrodes near the Fermi level is almost unchanged. However, for MnN, the right semiconductor nanoribbon is changed from 2HZ αBNR to NZ αBNR compared to MnH. The band gap is increased from 0.43 eV to 1.0 eV, which results in a decrease in the matching degree of the left and right electrodes near the Fermi level. Therefore, the transport properties of MnH and M ^{′}nH are almost same, while the MnH and MnN are obviously different. This result indicates that changing the left part metallic nanoribbon has a little effect on the transport properties of the junction; however, changing the right part semiconductor nanoribbon has a great influence on it.
To further understand the details of the rectification behavior for the heterojunctions, we calculated the transmission spectra at several certain biases, as shown in Fig. 5, where the above/below part shows the transmission spectra of the junction under the positive/negative bias. According to the LandauerBüttiker formula, we know that the current in the junction is directly related to the integrated area of the transmission spectrum within the bias window [47–49]. From the transmission spectrum shown in Fig. 5, we can see that the three types of models have a common trend. In the bias window, the integrated area of the transmission spectrum decreases with the number of primitive cells in the semiconductor part is increased. This is why the current in the heterojunction decreases with the number of cells in the semiconductor portion is increased, as shown in Fig. 3. Figure 5a shows the transmission spectra of the heterojunctions MnH at ± 0.3 V. For M1H, the integral area of the transmission spectrum in the bias window at 0.3 V is only slightly greater than − 0.3 V. Hence, the current of 0.3 V is only slightly higher than − 0.3 V, and the RR is only 3 at the bias 0.3 V. However, for M5H and M10H, the integral area of the transmission spectrum under positive bias in the bias window is significantly greater than under negative bias. This leads to the current of the M5H and M10H under positive bias being greater than under negative bias, and the RR is much larger than M1H. Figure 5b shows the transmission spectra of M ^{′}nH at ± 0.3 V. From the figure, one can see that the transmission spectra of M ^{′}nH in the bias window are almost the same as MnH. Therefore, under the same bias voltage, the current and the RR of M ^{′}nH and MnH are nearly the same [see Fig. 3b, e]. The transmission spectra of MnN at ±0.9 V are shown in Fig. 5c. Since the transmission coefficients in the bias window are too small, we magnify the transmission spectra in the bias window and attach it as an inset to the lower right side of Fig. 5c. The trend of the M1N transmission spectrum in the bias window is similar to the M1H and M ^{′}1H. Therefore, the RR of M1N is also small. For M5N and M10N, the integral area of the transmission spectrum under positive bias in the bias window is much larger than the area under negative bias. Therefore, compared with M1N, the asymmetric characteristics of these I−V curves are more obvious. This implies that they have a large rectification ratio. It is worth mentioning that the RR of M10N can reach 240, which is the best among the three types heterojunction.
In order to more intuitively explain the transmission spectrum in Fig. 5, we show the transmission eigenstate of M5H and M ^{′}5H at V = 0.3 V, E = − 0.15 eV, and V = − 0.3 V, E = 0.15 eV in Fig. 6a and b, respectively. And the transmission eigenstate of M5N at V = 0.9 V, E = − 0.45 eV, and V = − 0.9 V, E = 0.45 eV are shown in Fig. 6c [15, 16, 49]. The analysis of transmission eigenstate can obtained by linearly combining the propagating Bloch states \(\sum _{m}C_{a,m}\psi _{m}\). The C_{a,m} can be derived from the diagonalization of the transmission matrix, i.e., \({\sum \nolimits }_{n}T_{mn}C_{a,n}\)= λ_{a}C_{a,m}, where λ_{a} is the transmission eigenvalue. As can be seen from Fig. 6, for all heterojunctions, the transmission eigenstate under negative bias is located in the metallic part (unpassivated Z αBNR and 1HZ αBNR). At positive bias, the transmission eigenstate is mostly localized on the left part. However, it forms a transmission channel in the heterojunction. The electrons can be transferred from the left electrode to the right electrode. Therefore, in the bias window, the transmission coefficient under positive bias is greater than the under negative bias. In comparison Fig. 6a with b, one can see that the transmission eigenstate of M ^{′}5H and M5H are only slightly different. Thus, the heterojunctions M ^{′}5H and M5H have almost the same transmission coefficients in the bias window. In addition, for M5N, since the band gap of the semiconductor part increases, which results in more dramatic electronic scatter in the heterojunction. Therefore, only a few of the transmission eigenstates can be transmitted to the right side. This led to the transmission coefficient of MnN in the bias window is smaller than that of the other two types of heterojunction. Meanwhile, at the same bias, the current of MnN is the smallest of the three types of heterojunctions.
Finally, in order to further explore the effect of the left and right nanoribbons on the transport properties with heterojunctions, Fig. 7 shows the projected density of states (PDOS) of the three types of heterojunctions. From Fig. 7a, one can see that the PDOS spectra contributed by the left electrodes (unpassivated Z αBNR) of the junctions M1H, M5H, and M10H with overlap together near the Fermi level. This indicates that the PDOS contributed by the left electrode is hardly affected by the extension of the semiconductor nanoribbon (2HZ αBNR) in the center scattering region. However, the PDOS spectra contributed by the right electrode (2HZ αBNR) has a gap near the Fermi level. This is caused by a band gap near the Fermi level of the right electrode [see Fig. 3c]. Affected by the extension of the intermediate scattering region 2HZ αBNR, the PDOS spectra contributed by the right electrodes of junctions M1H, M5H, and M10H differ greatly from each other in the energy range outside the band gap. Since there are no essential difference between the two electrodes for heterojunction M ^{′}nH and MnH, the right electrode is the same and the left electrode is metallic ribbon. So, the PDOS of M ^{′}nH and MnH are almost the same near the Fermi level, as shown in Fig. 7a, b. This is one of the reasons why the transmission spectrum, I−V curves and RR of MnH and M ^{′}nH are similar under low bias [see Figs. 3 and 5]. In Fig. 7c, we present the PDOS of the MnN. Due to the band gap of the semiconductor part in the heterojunction increases, the effect of the left electrode on transmission properties becomes smaller. Therefore, PDOS overlaps each other within a larger energy range near the Fermi level. The PDOS spectrum contributed by the right electrode exists a gap in the energy range of (− 0.5, 0.5) eV. They are consistent with the position of the gap with N −ZBNR band structure. From the PDOS, we can conclude that the left side metal electrode has little effect on the transport properties of the intermediate scattering region. However, the semiconductor part electrode on the right is critical to the transport properties of the intermediate scattering region.
Conclusions
In summary, we have studied the transport properties of α−borophene based three type heterojunctions. We found that the three types of heterojunctions exhibit rectification behavior, among which the rectification ratio of heterojunction Z αBNR/NZ αBNR can reach up to 240. Moreover, as the number of unit cells in the central semiconductor part increases, the effect of rectification becomes more obvious. The origin of the rectification behavior is revealed and discussed by analyzing the transmission spectra and eigenstates under positive/negative bias. The rectification behavior of the heterojunctions strongly depends on the band gap value of the nanoribbons in the semiconductor part. This conclusion was further confirmed by analyzing PDOS contributed by the left and right electrodes. Our results provide new lines for the design of rectifying electronic devices.
Availability of Data and Materials
The design of nanojunctions and computational calculations were carried out by ATK.
Abbreviations
 2D:

Twodimensional
 TMD:

Transition metal dichalcogenides
 GMR:

Giant magneto resistance
 NDR:

Negative differential resistance
 DFT:

Density functional theory
 Z αBNR:

Zigzagedge αborophene nanoribbons
 H:

Hydrogen atom
 N:

Nitrogen atom
 1HZ αBNR:

The Z αBNRs with the edge passivated by one hydrogen
 2HZ αBNR:

The Z αBNRs with the edge passivated by two hydrogen atoms
 NZ αBNR:

The Z αBNRs with the edge boron atoms replaced by a nitrogen atom
 E _{ F } :

Fermi level
 ATK:

Atomistix toolKit
 NEGF:

The Keldysh nonequilibrium Green’s function
 PBE:

PerdewBurkeErnzerhof
 GGA:

Generalized gradient approximation
 BZ:

Borilliouin zone
 I−V curves:

Current −voltage curves
 RR:

Rectification ratio
 PDOS:

Projected density of states
References
 1
Geim AK (2009) Graphene: status and prospects. Science 324:1530–1534.
 2
Chen MX, Weinert M (2016) Halfmetallic Dirac cone in zigzag graphene nanoribbons on graphene. Phys Rev B 94:035433.
 3
Zhao JJ, Liu HS, Yu ZM, Quhe RG, Zhou S, Wang YY, Liu CC, Zhong HX, Han NN, Lu J, Yao YG, Wu KH (2016) Rise of silicene: a competitive 2D material. Prog Mater Sci 83:24–151.
 4
Chen MX, Weinert M (2014) Revealing the substrate origin of the linear dispersion of silicene/Ag(111). Nano Lett 14:5189–5193.
 5
Jariwala D, Sangwan VK, Lauhon LJ, Marks TJ, Hersam MC (2014) Emerging device applications for semiconducting twodimensional transition metal dichalcogenides. ACS Nano 8:1102–1120.
 6
Wang QH, KalantarZadeh K, Kis A, Coleman JN, Strano MS (2012) Electronics and optoelectronics of twodimensional transition metal dichalcogenides. Nature Nanotech 7:699–712.
 7
Liu H, Neal AT, Zhu Z, Luo Z, Xu XF, Tománek D, Ye PD (2014) Phosphorene: an unexplored 2D semiconductor with a high hole mobility. ACS Nano 8:4033–4041.
 8
Kou LZ, Chen CF, Smith SC (2015) Phosphorene: fabrication, properties, and applications. J Phys Chem Lett 6:2794–2805.
 9
Zhang A, Cao LM, Liu G, Liu ZR, Liao WH, Zhou GH (2019) The spintronic functionality in a junction of naphthalene diimide with different moleculegraphene linkers. J Magn Magn Mater 471:555–560.
 10
Zhai MX, Wang XF, Vasilopoulos P, Liu YS, Dong YJ, Zhou LP, Jiang YJ, You WL (2014) Giant magnetoresistance and spin Seebeck coefficient in zigzag αgraphyne nanoribbons. Nanoscale 6:11121–11129.
 11
Cao LM, Li XB, Zuo M, Jia CX, Liao WH, Long MQ, Zhou GH (2019) Perfect negative differential resistance, spinfilter and spinrectification transport behaviors in zigzagedged δgraphyne nanoribbonbased magnetic devices. J Magn Magn Mater 485:136–141.
 12
Maity A, Singh A, Sen P, Kibey A, Kshirsagar A, Kanhere DG (2016) Structural, electronic, mechanical, and transport properties of phosphorene nanoribbons: negative differential resistance behavior. Phys Rev B 94:075422.
 13
Karpan VM, Giovannetti G, Khomyakov PA, Talanana M, Starikov AA, Zwierzycki M, van den Brink J, Brocks G, Kelly PJ (2007) Graphite and graphene as perfect spin filters. Phys Rev Lett 99:176602.
 14
Wan HQ, Zhou BH, Liao WH, Zhou GH (2013) Spinfiltering and rectification effects in a Zshaped boron nitride nanoribbon junction. J Chem Phys 138:034705.
 15
Fan ZQ, Chen KQ (2010) Negative differential resistance and rectifying behaviors in phenalenyl molecular device with different contact geometries. Appl Phys Lett 96:053509.
 16
Li XB, Li HL, Wan HQ, Zhou GH (2015) Effects of aminonitro side groups on electron device of oligo pphenylenevinylene molecular between ZGNR electrodes. Org Electron 19:26–33.
 17
Zeng YJ, Wu D, Cao XH, Zhou WX, Tang LM, Chen KQ (2020) Nanoscale organic thermoelectric materials: measurement, theoretical models, and optimization strategies. Adv Funct Mater 30:1903873.
 18
Zeng YJ, Wu D, Cao XH, Feng YX, Tang LM, Chen KQ (2020) Significantly enhanced thermoelectric performance of molecular junctions by the twist angle dependent phonon interference effect. J Mater Chem A 8:11884–11891.
 19
Wu D, Cao XH, Jia PZ, Zeng YJ, Feng YX, Tang LM, Zhou WX, Chen KQ (2020) Excellent thermoelectric performance in weakcoupling molecular junctions with electrode doping and electrochemical gating. Sci China Phys Mech Astron 63:276811.
 20
Wu D, Cao XH, Chen SZ, Tang LM, Feng YX, Chen KQ, Zhou WX (2019) Pure spin current generated in thermally driven molecular magnetic junctions: a promising mechanism for thermoelectric conversion. J Mater Chem A 7:19037–19044.
 21
Marin EG, Marian D, Perucchini M, Fiori G, Iannaccone G (2020) Lateral heterostructure fieldeffect transistors based on twodimensional material stacks with varying thickness and energy filtering source. ACS Nano 14:1982–1989.
 22
Marian D, Dib E, Cusati T, Marin EG, Fortunelli A, Iannaccone G, Fiori G (2017) Transistor concepts based on lateral heterostructures of metallic and semiconducting phases of MoS _{2}. Phys Rev Appl 8:054047.
 23
Levendorf MP, Kim CJ, Brown L, Huang PY, Havener RW, Muller DA, Park J (2012) Graphene and boron nitride lateral heterostructures for atomically thin circuitry. Nature 488:627–632.
 24
Liu XL, Hersam MC (2019) Borophenegraphene heterostructures. Sci Adv 5:6444.
 25
Feng BJ, Sugino O, Liu RY, Zhang J, Yukawa R, Kawamura M, Iimori T, Kim H, Hasegawa Y, Li H, Chen L, Wu KH, Kumigashira H, Komori F, Chiang TC, Meng S, Matsuda I (2017) Dirac fermions in borophene. Phys Rev Lett 118:096401.
 26
Ezawa M (2017) Triplet fermions and Dirac fermions in borophene. Phys Rev B 96:035425.
 27
Zhou HB, Cai YQ, Zhang G, Zhang YW (2017) Superior lattice thermal conductance of singlelayer borophene. npj 2D Mater Appl 1:14.
 28
Kistanov AA, Cai YQ, Zhou K, Srikanth N, Dmitriev SV, Zhang YW (2018) Exploring the charge localization and band gap opening of borophene: a firstprinciples study. Nanoscale 10:1403–1410.
 29
Liu YY, Penev ES, Yakobson BI (2013) Probing the synthesis of twodimensional boron by firstprinciples computations. Angew Chem Int Ed 52:3156–3159.
 30
Zhang ZH, Yang Y, Gao GY, Yakobson BI (2015) Twodimensional boron monolayers mediated by metal substrates. Angew Chem Int Ed 54:13022–13026.
 31
Feng BJ, Zhang J, Zhong Q, Li WB, Li S, Li H, Cheng P, Meng S, Chen L, Wu KH (2016) Experimental realization of twodimensional boron sheets. Nat Chem 8:563–568.
 32
Zhong Q, Zhang J, Cheng P, Feng BJ, Li WB, Sheng SX, Li H, Meng S, Chen L, Wu KH (2017) Metastable phases of 2D boron sheets on Ag(111). J Phys Condens Matter 29:095002.
 33
Mannix AJ, Zhou XF, Kiraly B, Wood JD, Alducin D, Myers BD, Liu XL, Fisher BL, Santiago U, Guest JR, Yacaman MJ, Ponce A, Oganov AR, Hersam MC, Guisinger NP (2015) Synthesis of borophenes: anisotropic, twodimensional boron polymorphs. Science 350:1513–1516.
 34
Li WB, Kong LJ, Chen CY, Gou J, Sheng SX, Zhang WF, Li H, Chen L, Cheng P, Wu KH (2018) Experimental realization of honeycomb borophene. Sci Bull 63:282–286.
 35
Tang H, IsmailBeigi S (2007) Novel precursors for boron nanotubes: the competition of twocenter and threecenter bonding in boron sheets. Phys Rev Lett 99:115501.
 36
Penev ES, Bhowmick S, Sadrzadeh A, Yakobson BI (2012) Polymorphism of twodimensional boron. Nano Lett 12:2441–2445.
 37
Ding Y, Yang XB, Ni J (2008) Electronic structures of boron nanoribbons. Appl Phys Lett 93:043107.
 38
Cai YQ, Zhang AH, Feng YP, Zhang C (2011) Switching and rectification of a single lightsensitive diarylethene molecule sandwiched between graphene nanoribbons. J Chem Phys 135:184703.
 39
Brandbyge M, Mozos JL, Ordejón P, Taylor J, Stokbro K (2002) Densityfunctional method for nonequilibrium electron transport. Phys. Rev B 65:165401.
 40
Taylor J, Guo H, Wang J (2001) Ab initio modeling of quantum transport properties of molecular electronic devices. Phys Rev B 63:245407.
 41
Soler JM, Artacho E, Gale JD, García A, Junquera J, Ordejón P, SánchezPortal D (2002) The SIESTA method forab initioorderN materials simulation. J Phys Condens Matter 14:2745–2779.
 42
Wang BG, Wang J, Guo H (2001) Nonlinear spin polarized transport through a ferromagneticnonmagneticferromagnetic junction. J Phys Soc Jpn 70:2645–2651.
 43
Büttiker M, Imry Y, Landauer R, Pinhas S (1985) Generalized manychannel conductance formula with application to small rings. Phys Rev B 31:6207–6215.
 44
Yuan JR, Chen YP, Xie Y, Zhang XY, Rao DW, Guo YD, Yan XH, Feng YP, Cai YQ (2020) Squeezed metallic droplet with tunable Kubo gap and charge injection in transition metal dichalcogenides. Proc Natl Acad Sci USA 117:6362–6369.
 45
Fan ZQ, Sun WY, Jiang XW, Luo JW, Li SS (2017) Two dimensional Schottky contact structure based on inplane zigzag phosphorene nanoribbon. Org Electron 44:20–24.
 46
Zhao WK, Cui B, Fang CF, Ji GM, Zhao JF, Kong XR, Zou DQ, Jiang XH, Li DM, Liu DS (2015) Rectification inversion in oxygen substituted graphynegraphenebased heterojunctions. Phys Chem Chem Phys 17:3115–3122.
 47
Cao LM, Li XB, Jia CX, Liu G, Liu ZR, Zhou GH (2018) Spincharge transport properties for graphene /graphyne zigzagedged nanoribbon heterojunctions: a firstprinciples study. Carbon 127:519–526.
 48
Li XB, Li Y, Zhang XJ, Long MQ, Zhou GH (2019) Spinresolved electronic and transport properties of graphynebased nanojunctions with different nsubstituting positions. Nano Res Lett 14:299.
 49
Zhu L, Zou F, Gao JH, Fu YS, Gao GY, Fu HH, Wu MH, Lu JT, Yao KL (2015) The integrated spintronic functionalities of an individual highspin state spincrossover molecule between graphene nanoribbon electrodes. Nanotechnology 26:315201.
Acknowledgements
Not applicable.
Funding
This work was supported by the National Natural Science Foundation of China (Grant No. 11774085), Jiangxi university of traditional Chinese medicine 1050 youth talent project (Grant No. 5142001010), and the Natural Science Foundation of Hunan Province (Grant No. 2018JJ3521).
Author information
Affiliations
Contributions
GY conceived the idea and carried out the density functional theory simulation. GZ provided guidance in all aspects of the study. GY, WD, XX, and XL participated in the design of the study and performed the data analyze. All authors read and approved the final manuscript.
Corresponding author
Ethics declarations
Competing Interests
The authors declare that they have no competing interests.
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Yu, G., Ding, W., Xiao, X. et al. Rectifying Performance of Heterojunction Based on αBorophene Nanoribbons with Edge Passivation. Nanoscale Res Lett 15, 185 (2020). https://doi.org/10.1186/s11671020034177
Received:
Accepted:
Published:
Keywords
 αBorophene nanoribbon
 Lateral heterojunction
 Rectification effect
 Firstprinciples calculation