Control of Thermal Conductance across Vertically Stacked Two-Dimensional van der Waals Materials via Interfacial Engineering

Abstract

A comprehensive understanding of the roles of various nanointerfaces in thermal transport is of critical significance but remains challenging. A two-dimensional van der Waals (vdW) heterostructure with tunable interface lattice mismatch provides an ideal platform to explore the correlation between thermal properties and nanointerfaces and achieve controllable tuning of heat flow. Here, we demonstrate that interfacial engineering is an efficient strategy to tune thermal transport via systematic investigation of the thermal conductance (G) across a series of large-area four-layer stacked vdW materials using an improved polyethylene glycol-assisted time-domain thermoreflectance method. Owing to its rich interfacial mismatch and weak interfacial coupling, the vertically stacked MoSe 2 -MoS 2 -MoSe 2 -MoS 2 heterostructure demonstrates the lowest G of 1.5 MW m −2 K −1 among all vdW structures. A roadmap to tune G via homointerfacial mismatch, interfacial coupling, and heterointerfacial mismatch is further demonstrated for thermal tuning. Our work reveals the roles of various interfacial effects on heat flow and highlights the importance of the interfacial mismatch and coupling effects in thermal transport. The design principle is also promising for application in other areas, such as the electrical tuning of energy storage and conversion and the thermoelectricity tuning of thermoelectronics.

Superelastic, Highly Conductive, Superhydrophobic, and Powerful Electromagnetic Shielding Hybrid Aerogels Built from Orthogonal Graphene and Boron Nitride Nanoribbons

“…The d -spacing between BNNR and horizontal graphene lattices is measured to be 0.351 nm, which is very close to that of theoretical value of graphite (bottom right inset in Figure j). This suggests a strong interfacial coupling in OSG/BNNR hybrids, which is very conducive to the phonon transportation near their heterointerfacial area. − As the growth time prolongs to 4 h, rich vertical graphene sheets can be clearly observed on the horizontal graphene layers (Figure k). It is ascribed to the increased concentration of oxidizing gaseous byproducts, such as H 2 O and CO 2 derived from the pyrolysis of CH 3 OH .…”

“…Based on the above research, transferring CVD-grown graphene onto ceramic nanomaterials could be an effective strategy to integrate the extraordinary conductive feature offered by graphene and excellent mechanical flexibility given by ceramic nanomaterials, by which a desirable aerogel with combined elasticity and high thermal and electrical conductivity may be produced. Among the ceramic nanomaterials, hexagonal (h) BNNR could be a promising candidate owing to its superiorities, including the following: (i) intrinsic high thermal conductivity, (ii) few surface charge traps that do not disturb the electronic structure of graphene, (iii) low lattice mismatch with graphene in favor of reducing interfacial phonon scattering, − (iv) higher aspect ratio than those of 2D discrete nanosheets, and (v) larger mechanical deformability than those of 1D nanofibers/nanowires/nanotubes with weak point-linking pattern . Additionally, compared to horizontally grown graphene with typical layered structures and exceptional conductive properties, vertically grown graphene with open graphitic edges possesses superior electromagnetic wave (EMW) absorption ability attributed to its rich structural defects and strong charge polarization capability. , Providing that the orthogonally structured graphene (OSG, containing both horizontal and vertical graphene) is grown onto BNNRs, it will not only provide highways for carrier transportation but also greatly enhance the EMI shielding effectiveness (SE), and meanwhile render additional benefit, i.e., increasing the surface roughness capable of delivering highly hydrophobic capacity.…”

Activating lattice oxygen of two-dimensional MnXn−1O2 MXenes via zero-dimensional graphene quantum dots for water oxidation

“…This work demonstrates that the OER activity can be highly enhanced through a rational design by activating lattice oxygen. Considering the large family of MXenes, many MXene-based heterostructure catalysts are expected to be fabricated based on our vdW heterostructure design concept [63].…”

Heat Conduction Behavior of Two-Dimensional Nanomaterials and Their Interface Regulation※

“…与化学气相沉积法生长的紧密 结构不同, 通过转移制备的多层异质结构具有较弱的界 面耦合, 界面传热被抑制. 此外, 异质结构中丰富的界 面失配导致界面声子散射增强, 阻碍纵向热传导 [28] , 如 图 6a 所示.…”

“…图 6 (a)界面耦合和界面声子散射对纵向热导率的影响 [28] ; (b)层间旋转对石墨烯/六方氮化硼异质结构纵向热导率的影响 [31] Figure 6 (a) Effects of interfacial coupling and interfacial phonon scattering on longitudinal thermal conductivity [28] ; (b) effect of interlaminar rotation on longitudinal thermal conductivity of graphene/hexagonal boron nitride heterostructures [31] 化 学 学 报 综述 图 7 锂离子插层浓度对石墨烯(a)面内热导率和(b)纵向热导率的影响 [105] ; (c)锂离子插层 MoS 2 的热导率测试示意图 [110] ; (d)锂离子插层 MoS 2 的热 导率各向异性增强 [110] Figure 7 Effects of lithium ion intercalation concentration on (a) in-plane and (b) longitudinal thermal conductivity of graphene [105] ; (c) schematic diagram of thermal conductivity test of lithium ion intercalated MoS 2 [110] ; (d) thermal conductivity anisotropy of lithium ion intercalated MoS 2 is enhanced [110] 4 总结及展望…”