Stacking Order Research Articles

Transport properties in ABC-ABA-ABC trilayer graphene junctions

Trilayer graphene (TLG) consists of three layers of graphene arranged in a particular stacking order. In the case of ABC-ABA-ABC stacking, the layers are arranged in an A-B-C sequence, followed by an A-B-A sequence, and again an A-B-C sequence. This stacking arrangement introduces specific electronic properties and band structures due to the different stacking configurations. We focus on elucidating the transport properties of a p-n-p junction formed with ABC-ABA-ABC stacking TLG. Employing the transfer matrix method and considering continuity conditions at the junction boundaries, we establish transmission and reflection probabilities, along with conductance. Notably, electron transport through the ABC-ABA-ABC junction exhibits Klein tunneling, resulting in substantial conductance even in the absence of a potential barrier V 0. This effect arises from the effective barrier induced by our specific stacking, facilitating the passage of a maximal number of electrons. However, the presence of V 0 diminishes Klein tunneling, leading to conductance minima. Furthermore, our findings highlight that interlayer bias δ induces a hybridization of the linear and parabolic bands of ABA-TLG within the junction, reducing resonances. In cases where δ ≠ 0 and V 0 ≠ 0, we observe a suppression of the gap, contrary to the results obtained in ABC tunneling studies where a gap exists.

Effect of Mo and W underlayers on ordered phase formation in Fe-Au-Pd multilayer thin films at low temperatures

Fe-Pd based thin films with Au intermediate layer fabricated on different substrates (SiO2, SiO2/Mo, SiO2/W) were investigated at annealing temperatures up to 460°C. The samples were deposited by magnetron sputtering and were post-annealed in vacuum. The ongoing processes were investigated by chemical depth profiling and X-ray diffraction. The experimental results showed that the intermediate Au layer always promoted the formation of FePd3 phase which also showed L12 ordered structure except in one case with W underlayer. However, in the samples with Mo buffer but without the Au interlayer the FePd phase formed and L10 ordered phase also appeared for one stacking order. Considering the low diffusivity arising from the annealing temperature the processes were explained by grain boundary diffusion induced reaction layer formation. The formation of the ordered FePd phases was interpreted by the stress accumulation due to the different diffusivity of the components, which relaxes by the shift of the grain boundaries and the transformation of swept over regions. It was concluded, that the effect of the Au interlayer is dominant over the effect of the Mo or W buffer layers.

Directional heat treatment technique to prepare columnar grains in a TiAl alloy: Microstructure evolution and deformation behavior

Directional TiAl alloys show excellent comprehensive mechanical properties at high temperature (HT), and their notable attributes in high-temperature deformation resistance offer them promising application potential as structural materials in the aero engine industry. Directional heat treatment (DHT) is an effective local solid phase transformation technology in alloy processing and microstructure control. The directional Ti47Al2Nb2Cr alloys with columnar grains microstructure were fabricated via multiple DHT technology, where the HT deformation performance and corresponding deformation mechanism were both investigated. Results show that both the length in axial and width in radial are increasing with the increase of DHT time, together with the reduce of columnar grains amount, ultra-large columnar grains of 58.6 mm in length and 4.8 mm in width are even obtained, which makes it possible to realize the directional single crystals fabrication further, and the DHT-TiAl alloy may possess a tensile strength of 611.7 MPa at 800 ℃. For the first time, the mechanism of columnar grain growth is considered from the point of thermodynamics via analyzing the driving force of different DHT regions, which is thought to be greatly related to the temperature gradient, and the rule of preferred orientation choosing for columnar grains growth is discussed as well, then we defined the possible conditions of controlling columnar grains steady growth. Eventually, the detailed deformation mechanism of the multiple-DHT treated TiAl alloy was analyzed by transmission electron microscopy (TEM), which demonstrates that the twin intersections together with stress-induced γ variants within γ matrix, and the well-known long period stacking order (LPSO) structure 6 R and 9 R characterized by periodic stacking fault both found near α2 phase and γ twins/pseudo-twins further improved the plastic deformation accommodation and interface compatibility of DHT-TiAl alloy. This observed microstructure transformation and corresponding mechanical performance improvement demonstrate the potential of DHT technology in microstructure improving and properties strengthening for TiAl alloys during practical manufacturing process.

Two-dimensional Mo decorated borophenes: high critical temperature, large magnetic anisotropy, and stacking-dependent magnetism

Two-dimensional magnetic materials with high critical temperature, large magnetic anisotropy energy and intrinsic magnetism hold great promise for advancements in spintronics. However, synergizing these attributes within a single material remains challenging. Through the application of swarm-intelligence-based structure searching along with first-principles calculations, we identify two Mo decorated borophene variants, denoted as MoB4 and MoB6, are such candidates with high thermal and dynamical stabilities. MoB4 and MoB6 are characterized as either ferromagnetic or antiferromagnetic metals. Notably, both MoB4 and MoB6 display sizable magnetic anisotropy energy—924 and 932 μeV per Mo atom, respectively—surpassing that of the widely studied CrI3 monolayer, which measures 685 μeV per Cr atom. Monte Carlo simulation suggests the Curie temperature of MoB4 sheet is 390 K, which is above room temperature. Our examination uncovers that bilayer Mo x B y formations exhibit layer-specific van der Waals interactions, contrasting with bilayer borophenes produced experimentally, which display robust interlayer chemical bonding. We determine that the stacking order profoundly influence both the magnetic anisotropy energy and critical temperatures of the material. Specifically, the magnetic anisotropy energy for both structures doubles in their bilayer configurations, with AB-stacked MoB4 and AC-stacked MoB6 demonstrating critical temperatures of 550 K and 320 K, respectively. The exceptional electronic and magnetic characteristics of the Mo x B y monolayers position them as favorable candidates for future spintronic devices.

Homoepitaxy of Boron Nitride on Exfoliated Hexagonal Boron Nitride Flakes.

Although large efforts have been made to improve the growth of hexagonal boron nitride (hBN) by heteroepitaxy, the non-native substrates remain a fundamental factor that limits the quality. This problem can be solved by homoepitaxy, which is the growth of hBN on hBN substrates. In this report, we demonstrate the homoepitaxial growth of triangular BN grains on exfoliated hBN flakes by Metal-Organic Vapor Phase Epitaxy and show by atomic force microscopy and photoluminescence that the stacking of these triangular islands can deviate from the AA' stacking of hBN. We show that the stacking order is enforced by the crystallographic direction of the edge of the exfoliated hBN flakes, with armchair edges allowing for centrosymmetric stacking, whereas zigzag edges lead to the growth of noncentrosymmetric BN polytypes. Our results indicate pathways to grow homoepitaxial BN with tunable layer stacking, which is required to induce piezoelectricity or ferroelectricity.

Charge Transfer in Graphene-MoS2 Vertical Heterostructures Tuned by Stacking Order and Substrate-Introduced Electric Field.

Vertical van der Waals heterostructures composed of graphene (Gr) and transition metal dichalcogenides (TMDs) have created a fascinating platform for exploring optical and electronic properties in the two-dimensional limit. Numerous studies have focused on Gr/TMDs heterostructures to elucidate the underlying mechanisms of charge-energy transfer, quasiparticle formation, and relaxation following optical excitation. Nevertheless, a comprehensive understanding of interfacial charge separation and subsequent dynamics in graphene-based heterostructures remains elusive. Here, we have investigated the carrier dynamics of Gr-MoS2 heterostructures (including Gr/MoS2 and MoS2/Gr stacking sequences) grown on a fused silica substrate under varying photoexcitation energies by comprehensive ultrafast means, including time-resolved terahertz (THz) spectroscopy, THz emission spectroscopy, and transient absorption spectroscopy. Our findings highlight the impact of the substrate electric field on the efficiency of modulating the interfacial charge transfer (CT). Specifically, the optical excitation in Gr/MoS2 generates thermal electron injection from the graphene layer into the MoS2 layer with photon energy well below A-exciton of MoS2, whereas the interfacial CT in the MoS2/Gr is blocked by the electric field of the substrate. In turn, photoexcitation of the A exciton above leads to hole transfer from MoS2 to graphene, which occurs for both Gr-MoS2 heterostructures with opposite stacking orders, resulting in the opposite orientations of the interfacial photocurrent, as directly demonstrated by the out-of-phase THz emission. Moreover, we demonstrate that the recombination time of interfacial exciton is approximately ∼18 ps, whereas the defect-assisted interfacial recombination occurs on a time scale of ∼ns. This study provides valuable insights into the interplay between interfacial CT, substrate effects, and defect engineering in Gr-TMDs heterostructures, thereby facilitating the development of next-generation optoelectronic devices.

Ballistic performance of flexible structures composed of UHMWPE fibers and airbag: Effects of the stacking order

A series of flexible structures incorporating an airbag and ultra-high molecular weight polyethylene (UHMWPE) fiber panels were designed as temporary architectures to offer both ballistic protective functions and lightweight constructions. Three primary structural configurations, monolithic structures (airbag or UHMWPE panel alone), bi-layer structures (airbag/ UHMWPE panel and UHMWPE panel/airbag), and sandwich structures (UHMWPE panel/airbag/ UHMWPE panel) were tested. A T12A carbon tool steel sphere with the diameter of 12.7 mm was utilized as the ballistic threat within an impact velocity range of 0–500 m/s. Investigations into the effect of stacking order on ballistic performance were carried out experimentally and numerically. The failure characteristics, ballistic limits, energy dissipations, impact processes and interaction effects of these structures are discussed. To facilitate the establishment of numerical models for impact analysis using ABAQUS, a material constitutive model of thermoplastic polyurethanes (TPU) including strain rate effect was developed. The numerical models of the monolithic single-sheet UHMWPE panel and airbag for impact analysis were subsequently verified by experiments in terms of impact processes and ballistic limits. The results reveal that arranging a few layers of UHMWPE panels in front of the airbag can improve the collapse ballistic limit while maintaining the failure ballistic limit. The inclusion of an airbag reduces the energy dissipation efficiency of composite structures. The potential to enhance ballistic protection through the combination of airbags and UHMWPE panels is highlighted. Stress dispersion and deformation restraint are identified as significant factors influencing the ballistic performance of the composite structures.

Chiral Stacking Identification of Two-Dimensional Triclinic Crystals Enabled by Machine Learning.

Chiral materials possess broken inversion and mirror symmetry and show great potential in the application of next-generation optic, electronic, and spintronic devices. Two-dimensional (2D) chiral crystals have planar chirality, which is nonsuperimposable on their 2D enantiomers by any rotation about the axis perpendicular to the substrate. The degree of freedom to construct vertical stacking of 2D monolayer enantiomers offers the possibility of chiral manipulation for designed properties by creating multilayers with either a racemic or enantiomerically pure stacking order. However, the rapid recognition of the relative proportion of two enantiomers becomes demanding due to the complexity of stacking orders of 2D chiral crystals. Here, we report the unambiguous identification of racemic and enantiomerically pure stackings for layered ReSe2 and ReS2 using circular polarized Raman spectroscopy. The chiral Raman response is successfully manipulated by the enantiomer proportion, and the stacking orders of multilayer ReSe2 and ReS2 can be completely clarified with the help of second harmonic generation and scanning transmission electron microscopy measurements. Finally, we trained an artificial intelligent Spectra Classification Assistant to predict the chirality and the complete crystallographic structures of multilayer ReSe2 from a single circular polarized Raman spectrum with the accuracy reaching 0.9417 ± 0.0059.

Direct observation and characterization of a novel long period stacking ordered phase in GH4169 alloy

As is widely recognized, the Long Period Stacking Ordered (LPSO) phase is an important strengthening phase in the rare earth magnesium alloys. The LPSO phase not only enhances the strength of the alloy, but also improves its plasticity, thereby effectively addressing the strength-ductility trade-off phenomenon. Therefore, the preparation of metallic materials containing LPSO phase provides a new idea for designing a new generation of high-strength and high-toughness alloys. In present study, A novel nano-sized LPSO phase is observed and characterized for the first time in GH4169 nickel-based alloy. The results show that the stacking sequence of the LPSO phase is ABCBCBA, which indicates that this LPSO phase has a 6H structure. Meanwhile, the orientation relationships between LPSO phase and the Ni matrix are (11–1)γ//(0006)LPSO and [011]γ//[2-1-10]LPSO.

Divergent Vibrational Property Induced by an Anomalous Layer Sequence in Two-Dimensional GaPS4.

Recently, various fundamental properties of GaPS4 such as anisotropy and strain-induced properties have been reported, but the impacts of the stacking sequence in layered materials remain ambiguous. This ambiguity is evident in the inconsistent Raman scattering data reported for GaPS4, suggesting a significant influence of stacking order on its physical properties. To demonstrate the discrepancies, this study investigates the vibrational characteristics of 2D GaPS4 under different stacking sequences using both experimental observations and theoretical models (AA and AB sequences) through density functional theory calculations. The results of our theoretical calculations revealed that the identical stacking sequence structure significantly influences the vibrational configurations of GaPS4, which results in divergent configurations of Raman scattering spectra including unidentified Raman peaks. Our study addresses not only the clarification of the ambiguity of experimental observations but also qualitative criteria to evaluate the degree of each stacking sequence.

Impact of ply stacking sequence on the mechanical response of hybrid Jute-Banana fiber phenoplast composites

Natural fiber composites are increasingly gaining popularity as a cost-effective and environmentally friendly alternative to synthetic fibers. Incorporating a variety of fibers enhances mechanical properties. The arrangement of fibers plays a crucial role in determining the mechanical characteristics of laminate composites. Therefore, the primary objective of this study is to investigate how the stacking order of jute (J) and banana (B) fibers affects the mechanical behaviour of composites made from phenolic resins. Four different fiber mat stacking sequences (J/B/B/J, B/J/J/B, J/B/J/B, and J/J/B/B) were used for developing the eco-fiber composites using the heat-press technique. Several mechanical parameters were assessed, including tensile strength, flexural strength, impact strength, and inter-laminar shear strength (ILSS). The experimental results indicated that the JBBJ composite exhibits superior tensile strength (46.65 MPa) and modulus (993 MPa) compared to the other composites due to the presence of high-strength jute fibers on the surface. Additionally, the flexural strength of the JBBJ composite (87.24 MPa) was found to be noteworthy. It was observed that the impact strength of jute fibers surpasses that of banana fibers. Consequently, the JBBJ composite demonstrates higher values for energy absorption (0.482 J) and impact strength (120 J m−1) compared to the other composites tested. Moreover, the JBBJ composite displays higher inter-laminar shear strength and hardness values compared to BJJB, JBJB, and JJBB by 30%, 35%, and 43%, respectively. Scanning electron microscope microphotographs reveal strong correlational fracture failure mechanisms, indicative of improved mechanical properties in the JBBJ composite. Based on the experimental results, it is evident that the JBBJ composite can be utilized in lightweight applications.

Stabilization of μm-scale rhombohedral ABC stacking-faults and absence of structural relaxation within disclination-rich structures in commercially available natural graphite and grafoil

The recent observation of superconductive effects in rhombohedral graphene and in pyrolytic graphite systems exhibiting stacking faults have attracted a significant attention. Here we report an advanced investigation of stacking faults in multilayered lamellae of natural graphite and grafoil, by employing a combination of Raman point/mapping spectroscopy, scanning and transmission electron microscopy (SEM, TEM/HRTEM). The presented work identifies significant local structural transitions and an anomalous stabilization of rhombohedral stacking order occurring within μm-scale ripplocation-like defect-structures (first-category of stacking fault). Interestingly, we demonstrate an abrupt enhancement in the intensity of the left shoulder of the 2D band (of the Raman spectra) in sample's regions exhibiting an intersection between these defect structures. Extensive Raman mapping analyses demonstrate coexistence of rhombohedral ABC and Bernal ABA phases also within other sample's regions (second category of stacking-fault). This interpretation is further supported by comparative analyses performed in as-purchased strain-rich grafoil films. Interestingly, no structural relaxation of rhombohedral ABC stacking into ABA Bernal ordering was found in the analysed defect-regions.

Influence of Stacking Order on the Structural and Optical Properties of Cu2ZnSnS4 Absorber Layer Prepared from DC-Sputtered Oxygenated Precursors

Several studies have attempted to overcome the sudden volume expansion of the precursor during sulfurization by the use of oxygen-containing precursors when growing the CZTS absorber. This work demonstrates the influence of precursor stacking orders on the properties of the CZTS thin film absorber layer from DC-sputtered oxygenated precursors for solar cell applications. CZTS absorber layers were prepared from three types of DC-sputtered stacks, namely, Zn-O/Sn/Cu, Sn/Zn-O/Cu, and Sn/Cu/Zn-O. The precursors were sequentially deposited on a soda lime glass (SLG) using DC-magnetron sputtering and annealed in a sulfur and nitrogen ambient. X-ray diffractometry (XRD) and Raman spectroscopy analyses reveal the formation of crystalline kesterite CZTS structure regardless of the precursor stacking order. Atomic force microscope (AFM) analysis showed that CZTS thin films grown from precursor stacks SLG/Zn-O/Sn/Cu and SLG/Sn/Zn-O/Cu had improved morphological properties with densely packed large grains compared to that with stack SLG/Sn/Cu/Zn-O. SLG/Zn-O/Sn/Cu is the best stack among the studied stacking orders since it exhibits large grains in the absorber layer, which is preferential for high-efficiency thin film solar cells. The use of oxygenated precursor with order Sn/Zn-O/Cu promises improved CZTS absorber properties as it exhibits better morphological properties.

First-principles study of the thickness-dependent shift current in γ-GeSe thin layers

We investigate the stable structure and optoelectronic properties of thin γ-GeSe layers through first-principles calculations. We examine three stacking configurations (A-A, A-B, and A-C) of adjacent quadruple layers (QLs), revealing the structural stability of A-C stacking. Due to broken inversion symmetry in atomically thin γ-GeSe layers, shift currents are generated, which are very sensitive to their stacking order and thickness. Despite similar optical absorption trends in A-B and A-C stackings, their shift current responses differ significantly. The shift current is notably decreased at odd-number stackings for all cases, attributed to opposite generated flows between the top and bottom surfaces. The analysis of orbital contributions reveals the charge shift's origin in γ-GeSe. We also explore mechanical modifications, such as sliding and strain, demonstrating the tunability of the shift current spectrum in γ-GeSe. This research enhances our understanding of the optoelectronic response in atomically thin materials, providing valuable insights for future applications.

Exploring the impact of hybridization on green composites: pineapple leaf and sisal fiber reinforcement using poly(furfuryl alcohol) bioresin

Abstract This study aimed to examine the mechanical and physical characteristics of hybrid composite prepared using bio-epoxy reinforced with natural fibers extracted from pineapple leaf (PLF) and sisal (SF). The hand lay-up technique was utilized to fabricate the hybridized composite from bi-directional pineapple leaf fiber and sisal fibers using various stacking sequences. In order to understand the impact of hybridization on these composites, physical properties including density, percentage volume of fiber (PVF), and water absorption capacity were ascertained for hybrid composite. In addition, the mechanical characteristics like the tensile, fracture toughness, flexural, and interlaminar shear (ILSS) tests were investigated. Poly(furfuryl alcohol) was prepared and used as bioresin and it was apparent that the addition of more PLF in terms of PVF into hybridized composites, the properties flexural, tensile, and ILSS of the bio-epoxy composites were notably improved. The mechanical properties of hybridized composites were markedly impacted by the stacking order. Inference revealed that the composite attained the maximal tensile strength of 70.8 MPa for alternative sequence of SF and PLF. The composite which contained SF on the outside, had outperformed compared to other hybrid composites in terms of fracture toughness (3302.3 J/m2) and interlaminar shear strength (16.1 MPa).

Metal-Semiconductor Behavior along the Line of Stacking Order Change in Gated Multilayer Graphene.

We investigated gated multilayer graphene with stacking order changes along the armchair direction. We consider that some layers cracked to release shear strain at the stacking domain wall. The energy cones of graphene overlap along the corresponding direction in the k-space, so the topological gapless states from different valleys also overlap. However, these states strongly interact and split due to atomic-scale defects caused by the broken layers, yielding an effective energy gap. We find that for some gate voltages, the gap states cross and the metallic behavior along the stacking domain wall can be restored. In particular cases, a flat band appears at the Fermi energy. We show that for small variations in the gate voltage, the charge occupying this band oscillates between the outer layers.

Dependence of the Structural and Magnetic Properties on the Growth Sequence in Heterostructures Designed by YbFeO3 and BaFe12O19.

The structure and the chemical composition of individual layers as well as of interfaces belonging to the two heterostructures M1 (BaFe12O19/YbFeO3/YSZ) and M2 (YbFeO3/BaFe12O19/YSZ) grown by pulsed laser deposition on yttria-stabilized zirconia (YSZ) substrates are deeply characterized by using a combination of methods such as high-resolution X-ray diffraction, transmission electron microscopy (TEM), and atomic-resolution scanning TEM with energy-dispersive X-ray spectroscopy. The temperature-dependent magnetic properties demonstrate two distinct heterostructures with different coercivity, anisotropy fields, and first anisotropy constants, which are related to the defect concentrations within the individual layers and to the degree of intermixing at the interface. The heterostructure with the stacking order BaFe12O19/YbFeO3, i.e., M1, exhibits a distinctive interface without any chemical intermixture, while an Fe-rich crystalline phase is observed in M2 both in atomic-resolution EDX maps and in mass density profiles. Additionally, M1 shows high c-axis orientation, which induces a higher anisotropy constant K1 as well as a larger coercivity due to a high number of phase boundaries. Despite the existence of a canted antiferromagnetic/ferromagnetic combination (T < 140 K), both heterostructures M1 and M2 do not reveal any detectable exchange bias at T = 50 K. Additionally, compressive residual strain on the BaM layer is found to be suppressing the ferromagnetism, thus reducing the Curie temperature (Tc) in the case of M1. These findings suggest that M1 (BaFe12O19/YbFeO3/YSZ) is suitable for magnetic storage applications.

Ferroelectricity in two-dimensional bilayers and multilayers of MgAl2S4

The promising applications of two-dimensional (2D) ferroelectrics have intrigued lots of studies. The van der Waals stacking as a successful method has been applied to obtain the 2D ferroelectrics from non-ferroelectric parent compounds. Applying this strategy to the new 2D MA2Z4 materials, We predict the sliding ferroelectricity in bilayer and multilayer MgAl2S4 structures by the first-principles calculations. The stacking order shows a significant impact on the physical properties, where staggered stacking in the bilayer or multilayer MgAl2S4 can induce ferroelectricity but direct stacking can not. The polarization of the bilayer or multilayer MgAl2S4 arises from the interlayer transfer of uncompensated charge between the faces and the outer layers, which can be switched by interlayer interface sliding. To manipulate the polarization strength, the external strain was applied and the material properties can be modulated. In addition, similar to the monolayer behavior in bulk ReS2, the electronic structures show little difference from monolayer to six-layer MgAl2S4. However, the polarization in MgAl2S4 is more than fifteen times as strong as that of the ReS2. Our work paves the way for further exploration into van der Waals semiconductor ferroelectric systems and the development of novel high-efficiency nonvolatile memory devices.

The interlayer magnetic interaction in the CrI$_3$/CrSe$_2$ heterostructure

Abstract Based on first-principles calculations, we systematically studied the stacking energy and interlayer magnetic interaction of the heterobilayer composed of CrI$_3$ and CrSe$_2$ monolayers. We found that the stacking order plays a crucial role in the interlayer magnetic coupling. Among all possible stacking structures, the AA-stacking is the most stable heterostructure, exhibiting interlayer antiferromagnetic interactions. Interestingly, the interlayer magnetic interaction can be effectively tuned by biaxial strain. A 4.3% compressive strain would result in a ferromagnetic interlayer interaction in all stacking orders. These results reveal the magnetic properties of CrI$_3$/CrSe$_2$ heterostructure, which is expected to be applied to spintronic devices.

Free vibration analysis of jute/kenaf/banana hybrid biocomposites: effects of various stacking sequences

This work provides an insight of the free vibration behaviour based on experimental modal analysis of hybrid natural fibre reinforced polymer composites fabricated via compression moulding method. This study aims to study the impact of different polymer matrices (vinyl ester and epoxy) and stacking order of different natural fibres (Jute, Kenaf and Banana) on the composite’s free vibration characteristics. Jute-Kenaf-Banana-Epoxy (JKBE) matrix composites exhibited enhanced free vibration properties compared to single fiber reinforcements, except the banana/epoxy composites. Additionally, Jute-Kenaf-Banana-Vinyl ester (JKBV) composites demonstrated improved free vibration properties in comparison to single fiber reinforcements, with the exception of kenaf/vinyl ester composites. Kenaf-Banana-Jute-Jute-Banana-Kenaf-Epoxy (KBJJBKE) and Kenaf-Banana-Jute-Jute-Banana-Kenaf-Vinyl ester (KBJJBKV) hybrid composites showed the highest natural frequencies of 68.36 Hz and 97.66 Hz, respectively. However, there was no significant improvements in the natural frequencies of Jute-Kenaf-Banana-Kenaf-Banana-Jute-Epoxy (JKBKBJE) and Jute-Kenaf-Banana-Kenaf-Banana-Jute-Vinyl ester (JKBKBJV) hybrid composites. The highest damping factor was observed for JKBKBJE (0.153) and JKBKBJV (0.224) hybrid composites. These hybrid composites with better free vibration properties shall be a potential candidate in the automobile interior applications.