Nanotechnology: Remove plagiarism in the attached document

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1. Remove the plagiarism to below 15% without changing the science. You need a good knowledge of thermoelectric properties of a material. Do NOT use a software.

2. Correct grammatical mistakes.

1 Literature review There has been an increasing wave of research on 2D materials, with a good number of researchers focussing on thermoelectric properties of 2D single element materials and 2D heterostructure materials. In the 1990s, the thermoelectric properties of a large number of nanomaterials have been widely recognized, and some recent scientists have studied this feature more deeply 1–9. A large number of theoretical and experimental studies have described the thermal and thermoelectric properties of graphene/h-BN heterostructure10. 1.1 2009 The measurement techniques for in-plane Seebeck and four-probe conductivity were first demonstrated on monolayer graphene samples in 200911–13.Anomalous Seebeck (Sxx = ΔVxx/ΔTxx) and Nernst (Sxy = ΔVxy/ΔTxx) signals were observed, in violation of the well-accepted Mott relation for metallic samples. This was especially seen to be true close to the charge neutrality point (CNP) away from the highly doped degenerate limit, where electron-hole puddles were purported to be present. In this resistive state, the carrier density is strongly inhomogeneous and also the effect of impurities was found to be nontrivial. The manifestation of this on the thermoelectric power (Seebeck and Nernst) was explained well using an effective medium theory14. 1.2 2015 Wang et al. used the first-principles density functional calculations combined with the nonequilibrium Green’s function to simulate the thermal transport and thermoelectric properties of the graphene/h-BN heterostructure in the AB stacking mode 15. They observed that thermal transport characteristics of graphene in the heterostructure are lower than that of pure graphene, but the Seebeck coefficient is enhanced due to the opening of the graphene band gap. The figure of merit, ZT of the graphene/h-BN superlattice is larger than that of pure graphene, with 44% enhancement15. From the formula 𝑍𝑇 = (𝑆^2 𝜎)𝑇/𝑘 , it can be seen that all of the factors that affect ZT are enhanced and lead to the enhancement of ZT itself. 1.3 2015 The Seebeck measurements across a graphene/h-BN/graphene heterostructurehas been determined by inducing a temperature gradient between the bottom and top graphene layers and measuring the corresponding thermoelectric voltage (∆V) across the heterostructure16. A temperature gradient (∆T) of 39 K and thermoelectric voltage (∆V) of almost 4 mV is observed in the device, which results in a Seebeck coefficient of -99.3 μV/K, a power factor (𝑆 2 𝜎) of 1.51 × 10–15 W/K2 , and a thermoelectric figure of merit of ZT = 1.05 × 10–6 for the graphene/h-BN/graphene heterostructure. While the overall thermoelectric energy conversion efficiency of this device is small, the relatively large Seebeck coefficient and temperature drops observed here indicate that the I–V characteristics of 2D heterostructures can contain an appreciable thermoelectric component. 16. 1.4 2016 The thermal and thermoelectric properties of the most structurally stable AB configuration among the heterostructures formed by vertical stacking of graphene and h-BN have been revealed in recent studies 15,17. Molecular dynamics simulations have been performed to study the interfacial thermal resistance (ITR) of a graphene/h-BN bilayer system as well as its one-dimensional counterpart, a concentric CNT/BNNT double-walled nanotube, based on the lumped capacity model. The calculated ITR is in an order of magnitude of 10-7-10-6 Km2/W and it monotonically decreases with temperature and interlayer/intertube coupling strength17. 1.5 2016 Recent experiments where the graphene was processed to be extremely clean with low defect density on an atomically smooth, high-k hexagonal boron nitride (h-BN) dielectric indeed verified predictions that electron-electron scattering can dominate at high temperatures. This enabled the exploration of rich physics, where strong inelastic collisions between electrons (e–e interactions) dominate, resulting in a violation of the Mott Relation18. Further, near the CNP, a plasma of electron–holes (unlike charge puddles shown previously in defect-dominated samples) manifested in large Seebeck values18,19 as well as a violation of the Wiedemann– Franz Law20. Studies have show that the thermoelectric performance of graphene can be significantly improved by using hexagonal boron nitride (hBN) substrates instead of SiO219. The power factor times temperature, reached values as high as 10.35 W·m−1·K−1. higher values of PF3D were reported, as large as 34.5 mW m−1 K−2 (converted from a 10.35 W m−1 K−1 (Figure 3c) powerfactor × temperature (PFT) value at 300 K).19. These large values are similar to the report of violation of the Mott Relation in clean samples and can be ascribed to hydrody- namic electrons as well18. 1.6 2017 Researchers have used the Molecular Dynamic (MD) simulation method to assess the thermal conductivity of single-layer graphene based on a multilayer h-BN substrate 21. They have demonstrated that bulk hexagonal boron nitride (h-BN) is a more appealing substrate to achieve high performance heat dissipation in supported graphene. Notable length dependence and high thermal conductivity have been observed in single layer graphene on h-BN substrate. At room temperature, the thermal conductivity of h-BN-supported SLG is as high as 1347.3 ± 20.5 Wm−1 K−1, which is about 77% of that for the suspended case, and is more than twice that of the SiO2-supported SLG. 1.7 2017 The thermoelectric figures of merit of pristine two-dimensional materials are predicted to be significantly less than unity22, making them uncompetitive as thermoelectric materials. Since the inplane transverse and longitudinal phonons are effectively filtered out from contributing to crossplane transport because they do not substantially alter the tunneling matrix elements, theoretical calculations predict enhanced cross-plane thermoelectric properties in van der Waals heterojunctions, including high ZT factors at room temperature 22. These researchers have analysed the thermoelectric performance of monolayer molybdenum disulphide (MoS2) sandwiched between two graphene monolayers. They observed that CP ZT can be as high as ~2.8 for the graphene/MoS2/graphene heterostructure. 1.8 2017 Researchers have used quantum transport and molecular dynamics (MD) simulations to calculate the electronic and thermal properties of polycrystalline graphene-hBN heterostructures 23. They have estimated the thermoelectric conversion ratio and found that it remains far too low to be useful for energy harvesting applications. The upper value of the figure of merit, 𝑍𝑇 = 𝑆 2 𝜎𝑇 𝑘 has been found which is quite small. For 40nm average grain size and 20% hBN, ZT~1x10-4 for a carrier concentration n=5x1012 cm-2 , which is quite small. Even for energies near the edge of the gap, where the see beck coefficient should be maximised, the value of ZT only reaches ~1x10-2. 1.9 2017 Other researchers observed that an effective “inter-layer phonon drag” determines the Seebeck coefficient (S) across the van der Waals gap formed in twisted bilayer graphene (tBLG)24. They have demonstrated that the cross-plane thermoelectric transport is driven by the scattering of electrons and interlayer layer breathing phonon modes, which thus represents a unique “phonon drag” effect across atomic distances. They calculated the cross-plane thermoelectric power-factor (S2Gcp), by combining the experimentally observed magnitudes of see beck coefficient, S and interlayer conductance, Gcp. They observed that, the maximum effective PFT = TS2Gcp/d, where d ≈ 0.4 nm is the van der Waals distance, increases with temperature, and can be as high as ≈ 0.3 Wm−1K−1 at room temperature. 1.10 LAST In summary, several researchers have used theoretical and experimental approaches to study the thermoelectric properties of graphene based 2D heterostructures. However, more study is needed to fully optimise the thermoelectric performance of these materials. Besides, there is need to explore the performance of other 2D heterostructures. 2 1. Reference Dresselhaus, M. S. et al. New directions for low-dimensional thermoelectric materials. Adv. Mater. 19, 1043–1053 (2007). 2. Shuai, J. et al. Recent progress and future challenges on thermoelectric Zintl materials. Mater. Today Phys. 1, 74–95 (2017). 3. Zhao, H. et al. High thermoelectric performance of MgAgSb-based materials. Nano Energy 7, 97–103 (2014). 4. Chang, C. & Zhao, L.-D. Anharmoncity and low thermal conductivity in thermoelectrics. Mater. Today Phys. 4, 50–57 (2018). 5. Liu, Z. et al. Tellurium doped n -type Zintl Zr 3 Ni 3 Sb 4 thermoelectric materials: Balance between carrier-scattering mechanism and bipolar effect. Mater. Today Phys. 2, 54–61 (2017). 6. Takaki, H. et al. Thermoelectric properties of a magnetic semiconductor CuFeS 2. Mater. Today Phys. 3, 85–92 (2017). 7. Mao, J. et al. Anomalous electrical conductivity of n-type Te-doped Mg 3.2 Sb 1.5 Bi 0.5. Mater. Today Phys. 3, 1–6 (2017). 8. He, R. et al. Improved thermoelectric performance of n-type half-Heusler MCo 1-x Ni x Sb (M = Hf, Zr). Mater. Today Phys. 1, 24–30 (2017). 9. Brull, S. Un modèle ES–BGK pour des mélanges de gaz. Comptes Rendus Math. 351, 775– 779 (2013). 10. Wang, J. et al. The thermal and thermoelectric properties of in-plane C-BN hybrid structures and graphene / h-BN van der Waals heterostructures. Mater. Today Phys. 5, 29–57 (2018). 11. Checkelsky, J. G. & Ong, N. P. Thermopower and Nernst effect in graphene in a magnetic field. Phys. Rev. B - Condens. Matter Mater. Phys. 80, 1–4 (2009). 12. Zuev, Y. M., Chang, W. & Kim, P. Thermoelectric and magnetothermoelectric transport measurements of graphene. Phys. Rev. Lett. 102, 1–4 (2009). 13. Wei, P., Bao, W., Pu, Y., Lau, C. N. & Shi, J. Anomalous thermoelectric transport of dirac particles in graphene. Phys. Rev. Lett. 102, 1–4 (2009). 14. Hwang, E. H., Rossi, E. & Das Sarma, S. Theory of thermopower in two-dimensional graphene. Phys. Rev. B - Condens. Matter Mater. Phys. 80, 1–5 (2009). 15. Wang, X.-M. & Lu, S.-S. First-Principles Study of the Transport Properties of GrapheneHexagonal Boron Nitride Superlattice. J. Nanosci. Nanotechnol. 15, 3025–3028 (2015). 16. Chen, C. C., Li, Z., Shi, L. & Cronin, S. B. Thermoelectric transport across graphene/hexagonal boron nitride/graphene heterostructures. Nano Res. 8, 666–672 (2015). 17. Li, T., Tang, Z., Huang, Z. & Yu, J. Interfacial thermal resistance of 2D and 1D carbon/hexagonal boron nitride van der Waals heterostructures. Carbon N. Y. 105, 566–571 (2016). 18. Ghahari, F. et al. Enhanced Thermoelectric Power in Graphene : Violation of the Mott Relation by Inelastic Scattering. 136802, 1–5 (2016). 19. Duan, J. et al. High thermoelectricpower factor in graphene/hBN devices. Proc. Natl. Acad. Sci. 113, 14272–14276 (2016). 20. Lewis, G. S. & Hering, S. V. 2 1 . 0343, 1–8 (1988). 21. Zhang, Z., Hu, S., Chen, J. & Li, B. Hexagonal boron nitride: A promising substrate for graphene with high heat dissipation. Nanotechnology 28, (2017). 22. Sadeghi, H., Sangtarash, S. & Lambert, C. J. Cross-plane enhanced thermoelectricity and phonon suppression in graphene/MoS2van der Waals heterostructures. 2D Mater. 4, 1–8 (2017). 23. Barrios-Vargas, J. E. et al. Electrical and Thermal Transport in Coplanar Polycrystalline Graphene-hBN Heterostructures. Nano Lett. 17, 1660–1664 (2017). 24. Mahapatra, P. S., Sarkar, K., Krishnamurthy, H. R., Mukerjee, S. & Ghosh, A. Seebeck Coefficient of a Single van der Waals Junction in Twisted Bilayer Graphene. Nano Lett. 17, 6822–6827 (2017).
Sue26 by Edward Ma Submission date: 03-Jan-2019 11:15PM (UT C-0700) Submission ID: 1061432901 File name: Literature_review2.docx (39.18K) Word count: 1772 Character count: 9839 Sue26 ORIGINALITY REPORT 79 % SIMILARIT Y INDEX 31% 75% 7% INT ERNET SOURCES PUBLICAT IONS ST UDENT PAPERS PRIMARY SOURCES 1 Jing Wu, Yabin Chen, Junqiao Wu, Kedar Hippalgaonkar. "Perspectives on Thermoelectricity in Layered and 2D Materials", Advanced Electronic Materials, 2018 20% Publicat ion 2 Jingang Wang, Xijiao Mu, Xinxin Wang, Nan Wang, Fengcai Ma, Wenjie Liang, Mengtao Sun. "The thermal and thermoelectric properties of in-plane C-BN hybrid structures and graphene/h-BN van der Waals heterostructures", Materials Today Physics, 2018 14% Publicat ion 3 4 Int ernet Source Phanibhusan S. Mahapatra, Kingshuk Sarkar, H. R. Krishnamurthy, Subroto Mukerjee, Arindam Ghosh. "Seebeck Coefficient of a Single van der Waals Junction in Twisted Bilayer Graphene", Nano Letters, 2017 Publicat ion 10% 7% 5 6 Int ernet Source José Eduardo Barrios-Vargas, Bohayra Mortazavi, Aron W. Cummings, Rafael Martinez-Gordillo et al. "Electrical and Thermal Transport in Coplanar Polycrystalline Graphene–hBN Heterostructures", Nano Letters, 2017 6% 6% Publicat ion 7 Ting Li, Zhenan Tang, Zhengxing Huang, Jun Yu. "Interfacial thermal resistance of 2D and 1D carbon/hexagonal boron nitride van der Waals heterostructures", Carbon, 2016 5% Publicat ion 8 9 10 Int ernet Source Int ernet Source Submitted to Indian Institute of Science, Bangalore 3% 3% 3% St udent Paper 11 12 Int ernet Source Int ernet Source 2% 1% Exclude quotes Of f Exclude bibliography On Exclude matches Of f Sue26 GRADEMARK REPORT FINAL GRADE GENERAL COMMENTS /0 Instructor PAGE 1 PAGE 2 PAGE 3 PAGE 4 PAGE 5

Tutor Answer

School: Duke University



Literature Review

Student name:
Institutional affiliation:

Literature Review
The attached word document addresses the question “Nanotechnology: Remove plagiarism in the
attached document” by answering the following:

Remove the plagiarism to below 15% without changing the science. You need a good
knowledge of thermoelectric properties of a material. Do NOT use a software.

Correct grammatical mistakes.

Running Head: Literature Review

Literature Review

Student name:
Institutional affiliation:

Literature Review

Literature review

With the increase research on 2D materials, many researchers have focused on the
thermoelectric properties of both the 2D heterostructure and 2D single element materials. The
thermoelectric properties of most nanomaterials was recognized around 1990s, with recent researchers
studying these characteristic in



. The thermoelectric and thermal characteristics of

graphene/h-BN heterostructure has been described by many experimental and theoretical studies 10.


The four-probe conductivity and in-plane Seebeck measurement techniques were initially
described on graphene monolayer samples in 200911–13. Nernst (Sxy = ΔVxy/ΔTxx) and Anomalous
Seebeck (Sxx = ΔVxx/ΔTxx) signals were detected, violating the Mott relation, which was well accepted
for samples made of metal, particularly observe next to the charge neutrality point (CNP) far from the
doped debased limit, which comprises of puddles of electron-holes. In such a resistive state, the
impurity effect was nontrivial and carrier density strongly inhomogeneous. An effective medium
theory was used to explained this manifestation on the thermoelectric power (Nernst and Seebeck)14.


Graphene/h-BN heterostructure’s thermoelectric properties and thermal transport in the mode
of AB stacking was simulated by Wang et al. using functional calculations of first-principles density
combined with the Green’s function of non-equilibrium


. They observed that graphene’s thermal

transport features within the heterostructure is lower in comparison to pure graphene. However,
graphene band gap enhances the coefficient of Seebeck. The ZT for pure graphene is smaller than that
of graphene/h-BN super lattice by a necessary enhancement of 44% 15. It f...

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