Pristine Case Research Articles

The influence of intrinsic point defects on the electronic band structures and swelling behaviors of 4H-SiC

In this work, both the first principles calculations and molecular dynamics simulations are adopted to investigate the formation ability of various intrinsic point defects in 4H-SiC as well as the electronic band structure changes and the swelling effects caused by them. Our results demonstrate that the classical MEAM potential has an unsatisfactory performance on the defect formation energies as compared with the ab initio calculations based on the advanced SCAN functional, but provides a reasonable description on the volumetric swelling caused by single point defect. Both the SCAN and MEAM calculations indicate that the VC monovacancy and the CSi antisite defect will cause the lattice shrinkage, while the VSi monovacancy, the SiC antisite, the IC and the ISi interstitials will induce the volumetric swelling. Besides that, first principles calculations reveal that monovacancies and interstitials would induce defective electronic states near the Fermi level, while antisites have negligible influence on the electronic band structures as compared with the pristine case. Furthermore, the molecular statics relaxations are employed to explore the influence of point defect densities on the swelling behaviors of 4H-SiC, which reveals that the volume swelling ratios present good linear relationships with the increased density of the VC monovacancy, CSi antisite, SiC antisite and IC interstitial defects, but express complex non-linear tendencies with the VSi monovacancy and ISi interstitial defects. Therefore, our research deepens the understanding of the point defects’ effects on the electronic properties and swelling behaviors of 4H-SiC.

Li decorated graphdiyne nanosheets: A theoretical study for an electrode material for nonaqueous lithium batteries

In this work, Density Functional Theory (DFT) is used to study pristine and defective GDY. We investigate the effect of Li atom adsorption on the electronic and structural properties of this 2D material. In both cases, the Li atom is located at the corner of the triangular‐like pore (H1), but with a slight shift for the defective system. In the perfect system, the Li‐C bond distances range from 2.289 Å to 2.461 Å, while in the defective case, they range from 2.237 Å to 3.184 Å. In the perfect case, the GDY‐Li system becomes metallic and the Li 2s states are stabilized. Charge transfer to the surfaces occurs near the vicinity of the Li atom. The C vacancy generates new C=C bonds similar to double bonds, enhancing the interaction with Li through strong conjugation. After Li adsorption, the sum of bond order for all the C atoms increases in both structures, from 0.4% to 6%. The Li storage capacity without significant restructuring is six Li atoms. When the atom concentration increases, the OCV values for Li decrease from 0.93 V to 0.23 V. For defective GDY, the specific capacity is 788 mAhg‐1, which is slightly higher than for pristine case.

Full spin polarization and pure spin current produced by the photogalvanic effect in penta-PdN2 photodetector

The photogalvanic effects (PGEs) in low-dimensional devices were thought to be an important mechanism to generate pure spin current which was a essential problem in spintronics. Herein, based on non-equilibrium Green’s function combined with density functional theory, we studied linear and elliptical spin dependent PGEs in the photodetector based on the penta-PdN2 monolayer at zero bias. Due to spin-orbit coupling originating from the heavy metal atoms Pd and low symmetry of C2v for the pristine case and Cs for the defect cases, the penta-PdN2 photodetector at pristine, vacancy and substitution-doping situations can produce robust spin dependent PGEs, and the import of defects were able to strengthen the linear and elliptical PGEs, respectively. More importantly, on account of enormous splitting of the DOS for the pristine, Pd-vacancy, N2-vacancy and NN-vacancy cases, spin up and spin down photocurrents accordingly formed spin splitting, which eventually led to full spin polarization and then pure spin currents in the penta-PdN2 photodetector. PdSe2 monolayer has been compounded in experiments, so structurally similar penta-PdN2 monolayer possesses highly possible to be prepared. Therefore, if the penta-PdN2 photodetector can be successful assembled, the spin-generator will be reality, even no need to be doped because the pristine penta-PdN2 photodetector can give rise to pure spin currents. In addtion, the penta-PdN2 photodetector at different situations are highly polarization sensitive. In conclude, our work suggested great potential applications of the penta-PdN2 monolayer on PGE-driven low energy-consumption photodetectors and spin-generators in optoelectronics and spintronics.

Applying the first principle to study the structure, electrical and magnetic properties of ASiNRs-doped Neodymium

In this project, we investigated and investigated the optimal sites in the chemisorption of Neodymium (Nd) on armchair silicene nanoribbons (ASiNRs) to learn about the geometrical and electronic properties of the structures by applying these properties with first principle math. The survey has three steps. The first was to change the top, valley, bridge, and hollow positions to find optimazed positionThe results show that the Bridge position has the lowest absorbed energy value of -2.6eV, has the most stable structure, with the strongest magnetic moment of 4.68 μB, and a buckl degree of 0.69 Å; The Si-Si-Si bond angle at this time is 115053’ almost like the pristine case. The second was to change the Si-Si bondlength of ASiNRs the same purpose. Finally, we survey the distance from Nd atom to pristine adsorbent surface was decreased. The calculation results show that the valley position is the most ideal location, corresponding to the bond length of 2.26 Å and the optimal height of 2.11 Å resulting in a single material adsorption system for the new materials, different from other positions with bandgap changed. This result shows that the absorption method between metals and pristine semiconductor ASiNRs has opened up a very good direction, contributing to enriching the source of materials applied to the field of manufacturing electronic, optoelectronic, and spintronic components in the future.

CCN Activation and Droplet Growth in Pi Chamber Simulations with Lagrangian Particle–Based Microphysics

Abstract Numerical simulations of turbulent moist Rayleigh–Bénard convection driving CCN activation and droplet growth in the laboratory Pi chamber are discussed. Supersaturation fluctuations come from isobaric mixing of warm and humid air rising from the lower boundary with colder air featuring lower water vapor concentrations descending from the upper boundary. Lagrangian particle–based microphysics is used to represent the growth of haze CCN and cloud droplets with kinetic, solute, and surface tension effects included. Dry CCN spectra in the range between 2- and 200-nm radii from field observations are considered. Increasing the total CCN concentration from pristine to polluted conditions results in an increase in the droplet concentration and reduction in the mean droplet radius and spectral width. These are in agreement with Pi chamber observations and numerical simulations, as well as with numerous past studies of CCN cloud-base activation in natural clouds. The key result is that a relatively small fraction of the available CCN is activated in the Pi chamber fluctuating supersaturations, from about a half in the pristine case to only a 10th in the polluted case. The activation fraction as a function of the dry CCN radius is similar in all simulations, close to zero at the CCN small end, increasing to a maximum at CCN radius around 50 nm, and decreasing to close to zero at the large CCN end. This is explained as too small supersaturations to activate small CCN as in natural clouds and insufficient time to allow large CCN reaching the critical radius. Significance Statement Impact of turbulence on the formation and growth of cloud droplets is an important cloud physics problem. Laboratory experiments in the Michigan Technological University cloud chamber provide key insights into this problem. Numerical simulations of cloud chamber processes discussed in this paper complement laboratory experiments by providing insights difficult or impossible to obtain in the laboratory. The study contrasts the formation and growth of cloud droplets in the laboratory cloud chamber with processes taking place in natural clouds. The differences documented in this paper pose questions concerning the impact of turbulence on the formation and growth of cloud droplets as a result of interactions of clouds with their environment.

Unraveling the influence of surface functionalities on gas Physisorption: A comprehensive study on SBA-15 nanoporous material from Monte Carlo simulation for improved Textural-Energetic characterization

In this study, we conducted experimental and Monte Carlo simulation studies in the grand canonical ensemble (GCMC) to investigate the role of molecular orientation and surface heterogeneity on the adsorption of N2 at 77 K. Our research focused on a series of ordered nanoporous materials (SBA-15) with varying degrees of oxygen functionalities. Specifically, we examined the effects of surface heterogeneity on the calculation of pore size distribution (PSD) and the Brunauer-Emmett-Teller (BET) area of porous materials. To provide a comprehensive perspective, we compared our results with three levels of surface oxidation, including a pristine case without any surface oxidation.The results from both our experimental and simulation data reveal the importance of chemical heterogeneity in determining equilibrium properties such as molecular packing within the pores, differential enthalpies of adsorption, and N2 orientation distribution. Our findings suggest that accurate characterization of surface heterogeneity is crucial for understanding gas adsorption in nanoporous materials and for developing better models for predicting their performance in various applications. Moreover, our simulations revealed substantial changes in the molecular orientation of adsorbate particles with increasing surface heterogeneity. This insight provides valuable information about the behavior of molecules within the nanoporous materials, further enhancing our understanding of the complex adsorption processes in these systems.

Strain-induced modification in thermal properties of monolayer 1T-ZrS2 and ZrS2/ZrSe2 heterojunction.

This paper systematically analyzes the phonon dispersion curves of single-layer ZrS2, ZrSe2, and ZrS2/ZrSe2 heterostructures under different strains. The phonon spectra and thermal parameters of the three structures were obtained based on the density functional perturbation theory method. The upper limits of strain that different monolayers and heterojunctions can withstand were studied. The monolayers ZrSe2 and ZrS2 can withstand up to 8% biaxial tensile strain, and the ZrS2/ZrSe2 heterojunction can withstand up to 6% biaxial tensile strain. In addition, the van der Waals force of the heterojunction may cause phonon tearing in the vertical direction. The application of biaxial tensile strain can adjust the thermal properties of the system to a large extent, which is similar to the strain effect in the pristine case. When the temperature rises, the entropy enthalpy of the three structures also gradually increases, the free energy gradually decreases, and the heat capacity of the system gradually increases until it tends to be stable. Taking single-layer ZrS2 as an example, we analyzed the change curve of thermal properties of single-layer ZrS2 under tensile strain. The results show that with the gradual increase of strain, the crystal's entropy, enthalpy, and free energy change differently. In addition, the heat capacity increases slowly under high temperatures. When all systems reach the limit strain, the phonon spectrum appears to have an imaginary frequency, and the thermal properties decrease significantly. This paper uses the first-principle calculation method based on density functional theory, and the PBE exchange-correlation function based on generalized gradient approximation (GGA) is selected for a specific calculation. The density functional perturbation theory (DFPT) calculates the full kinetic matrix. Because the lattice constants of ZrS2 and ZrSe2 are similar and have similar periodicity, the corresponding unit cells are used for structural optimization and property calculation. The Brillouin zone is integrated using the K points generated by the Monkhorst-pack method. For single-layers ZrS2 and ZrSe2, 8 × 8 × 1K-point grid is selected, and for ZrS2/ZrSe2 heterojunction, 8 × 8 × 2K-point grid is selected. A vacuum layer of 30Å was added in the vertical direction to avoid interlayer interaction. The non-conservative pseudopotential method is used to optimize the structure, and the optimization convergence is set as follows: the cutoff energy is set to 700eV, the convergence threshold of the maximum force between atoms is 0.01eV/Å, the convergence threshold of the maximum energy change is set to 1 × 10-9eV, and the convergence threshold of the maximum displacement is 0.001Å.

Magnetic State Control of Non-van der Waals 2D Materials by Hydrogenation.

Controlling the magnetic state of two-dimensional (2D) materials is crucial for spintronics. By employing data-mining and autonomous density functional theory calculations, we demonstrate the switching of magnetic properties of 2D non-van der Waals materials upon hydrogen passivation. The magnetic configurations are tuned to states with flipped and enhanced moments. For 2D CdTiO3─a diamagnetic compound in the pristine case─we observe an onset of ferromagnetism upon hydrogenation. Further investigation of the magnetization density of the pristine and passivated systems provides a detailed analysis of modified local spin symmetries and the emergence of ferromagnetism. Our results indicate that selective surface passivation is a powerful tool for tailoring magnetic properties of nanomaterials, such as non-vdW 2D compounds.

Biaxial compressive strain enhances calcium binding and mobility on two-dimensional Sc2C: a density functional theory investigation.

In this work, we investigated calcium binding and diffusion on pristine and biaxially strained 2D Sc2C via density functional theory calculations, for potential applications in calcium-ion batteries (CIBs). We found that 2D Sc2C is metallic under PBE, HSE06, and DFT+U approximation conditions, and thus can be potentially used as an electrode material for CIBs. Results showed that pristine 2D Sc2C adsorbs calcium modestly, with relatively low binding energy on the most stable site (0.38 eV). Interestingly, this value shoots up to -1.94 eV and -3.23 eV at 5% and 10% biaxial compressive strains, respectively. Furthermore, calcium's diffusion energy barrier, which is already low (80 meV) on pristine 2D Sc2C, goes down further (to 35 meV) upon application of median biaxial compressive strain (5%). As a result of the enhanced binding of calcium on strained 2D Sc2C, the maximum stable calcium concentration was also boosted. Consequently, the calculated theoretical specific energy capacity of 2D Sc2C with biaxial compressive strain is higher compared to that of the pristine case (878.29 mA h g-1vs. 1051.84 mA h g-1). The average open circuit voltages of the two cases are high and quite close at 9.3 V (pristine) and 9.0 V (with 5% biaxial compressive strain). Our results demonstrated that biaxial compressive strain could be tapped to improve the properties of 2D MXenes, such as Sc2C, thereby enhancing the battery performance indicators of these materials, such as theoretical specific energy capacity and open circuit voltage. Such findings are of great importance in the emerging new technology of CIBs.

Effect of biaxial strain and vacancy defects in 2D MoS2 monolayer for the sensing of nitrobenzene: A DFT investigation

Considering the increased release of toxic nitrobenzene (NB) molecules into the atmosphere, proposing a sensor material that could effectively remove it from the environment is essential. In this regard, we have investigated the NB adsorption performance of vacancy-defected (S, Mo and di S) and biaxially strained (−4 % to 4 %) MoS2 monolayers through density functional theory (DFT) simulations. Applying biaxial (tensile and compression) strain to the monolayer significantly increased the adsorption energy and charge transfer to −1.02 eV and 0.09 e, respectively, much greater than in the pristine case. The formation energy calculations verified the stability of (S, Mo, 2S) vacancy-defected MoS2 monolayer. The low formation energy of 3.3 eV suggests the ease of formation of MoS2 monolayer with single S vacancy. Introducing defects and strain improved the conductivity of the monolayer, thereby increasing the NB adsorption ability. The reasonable NB adsorption energy on the modified monolayer was due to the accelerated charge transfer and orbital interaction between the valence S 3p orbitals of MoS2 and 2p orbitals of O in NB. The recovery time of the strained and defective monolayers is the order of only a few seconds at 400 K, which is quite attainable. Therefore, this work put forth a more effective to improve the NB performance of the monolayer and can be a motivation for the further development of high-performance biomolecule sensors.

Multistep magnetization switching in orthogonally twisted ferromagnetic monolayers.

The advent of twist engineering in two-dimensional crystals enables the design of van der Waals heterostructures with emergent properties. In the case of magnets, this approach can afford artificial antiferromagnets with tailored spin arrangements. Here we fabricate an orthogonally twisted bilayer by twisting two CrSBr ferromagnetic monolayers with an easy-axis in-plane spin anisotropy by 90°. The magnetotransport properties reveal multistep magnetization switching with a magnetic hysteresis opening, which is absent in the pristine case. By tuning the magnetic field, we modulate the remanent state and coercivity and select between hysteretic and non-hysteretic magnetoresistance scenarios. This complexity pinpoints spin anisotropy as a key aspect in twisted magnetic superlattices. Our results highlight control over the magnetic properties in van der Waals heterostructures, leading to a variety of field-induced phenomena and opening a fruitful playground for creating desired magnetic symmetries and manipulating non-collinear magnetic configurations.

The effect of chemistry and thermal fluctuations on charge injection barriers at aluminum/polyolefin interfaces

Charge injection at metal/polymer interfaces is a critical process in many technological devices, including high voltage capacitors and cables in which polyolefin materials, such as polyethylene (PE) and polypropylene (PP), are often used as insulation materials. We use simulations based on density-functional theory to study charge injection at aluminum/PE and aluminum/PP interfaces. Specifically, we investigate the influence of incorporating a variety of polar chemical impurities at the PE and PP chain ends on electron and hole injection barriers. Crucially, we account for the effect of thermal disorder by considering ensembles of thousands of interface structures obtained from ab initio molecular dynamics trajectories at 373 K. We show that the mean injection barrier can change by up to 1.1 eV for Al/PE and 0.6 eV for Al/PP, as compared to the pristine case, depending on which chemical impurity is introduced. We also show that the spread of injection barriers from thermal fluctuations also depends strongly on the chemistry of the impurity. The observed trends can be understood with a simple model based on thermal fluctuations of the dipole moment density associated with the chemical impurity at the interface. We further verify this model by considering larger interface models with lower impurity densities. Our results demonstrate that small chemical modifications, which may arise from oxidation, for example, have a significant influence on charge injection barriers in metal/polyolefin interfaces.

Engineering and controlling the electronic properties of zigzag and armchair boron nitride nanotubes with various concentrations of oxygen impurities

This research underscored the comprehension of the electronic properties of the various diameters for zigzag and armchair single-wall boron nitride (ZSWBNNTs and ASWBNNTs) under various concentrations of oxygen impurities. The electronic properties of these tubes are investigated by using the first density functional theory (DFT), which implemented in the QUANTUM ESPRESSO package. Results show that the electronic properties of all these tubes can be controlled by using different concentrations of oxygen impurities. In the pristine case, the electronic band gap of these tubes is deepened on the diameter. So, the electronic band gap is increased by increasing the diameter of the tube. Nevertheless, these properties are changed and affected by various concentrations of oxygen impurities. The electronic band gap of ZSWBNNTs reduced by using one and two -hexagonal of oxygen impurities, and the behavior of ASWBNNTs changed from insulator to semiconductor properties by using a 2-hexagonal of oxygen impurities. Our investigation revealed for the first time that the behaviors of ZSWBNNTs and ASWBNNTs are changed from semiconductor and insulator to metallic with seven oxygen impurities. Then, there are very fascinating results. Also, the electronic band gap doesn't only depend on the impurity concentration, but also depends on the geometrical pattern of oxygen impurities in the ASWBNNTs.

Mapping the impact of defect distributions in silicon carbide devices using the edge transient-current technique

We demonstrate that the multi-photon absorption edge transient-current technique (edge-TCT) can be used to three-dimensionally map the impact of defect distributions on device characteristics in situ inside the bulk of silicon carbide devices. A ∼5 μm wide defect-rich layer induced by proton irradiation at a depth of ∼27 μm was investigated in 4H-SiC samples and compared to the pristine case. Edge-TCT enables mapping of the position of the implantation peak as well as to identify the space charge polarity around the implanted region. The edge-TCT results are compared to Monte Carlo simulations of the proton irradiation that were verified by luminescence measurements and TCAD-based device simulations. In result, edge-TCT is found to be capable of distinguishing different device regions due to its charge sensitivity and directly visualizing space charge regions, facilitating calibration of charge carrier distribution models in semiconductor devices.

Multidirectional strain-induced thermoelectric figure of merit enhancement of zigzag bilayer phosphorene nanoribbons

We have theoretically investigated strain-induced thermoelectric power generation properties of zigzag bilayer phosphorene nanoribbon. Since energy bandgap size and edge state dispersion play a significant role in the thermoelectric properties of such a structure, we have investigated the effect of strain in different directions on these two quantities. We have shown that by applying both tensile and compressive strains in different directions, it is possible to properly tune the energy bandgap size and adjust the edge state dispersion. We have also selected strain combinations in different directions that simultaneously increase the size of the energy bandgap and decrease the dispersion of the edge state. It has shown that with such combinations of strains, the maximal figure of merit has been improved by about two times compared to the pristine case.

Investigation of the hexagonal boron nitride (h-BN) electronic and structural parameters and its dependency on the known semi-local functionals

Known as the next wonder material after graphene, hexagonal form of Boron-Nitride (hBN) attracts a lot of interest due to its capabilities to be utilized in wide range of applications. Here we investigate bilayer structure of hBN using density functional theory (DFT) techniques. In pristine case, we observed that the SCAN functional gives a significantly better estimation of inter-layer distance compared to the PBE functional. Furthermore, we also modelled the hBN structure with a single oxygen molecule sandwiched in between of B-N layer, and conclude that the most probable sites for oxygen molecule to be trapped is at the exact center of the bilayer hBN structure.

Anisotropic Li diffusion in pristine and defective ZnO bulk and (10[formula omitted]0) surface

We study the Li interstitial diffusion in pristine and defective ZnO bulk and (101¯0) surface by means of first-principles density functional theory (DFT) coupled with the Nudged Elastic Band (NEB) calculations. We consider three types of point defects, i.e., oxygen vacancy (Ovac), Zn vacancy (Znvac) and ZnO vacancy pair (ZnOvac-pair) and investigate their individual effect on the energy barrier of Li interstitial diffusion. Our results predict that Ovac and Znvac lower the Li diffusion energy barrier as compared to the pristine ZnO case. However, we further find that Li interstitial, on the other hand, may possibly be trapped inside the Znvac subsequently forming the LiZn substitutional type of defect. The similar behavior also observed for Li interstitial in the vicinity of Zn-Ovac_pair though with less change of Li diffusion barriers as compared to the other two cases. For Li diffusion on the ZnO surface, our results indicate that Ovac imposes similar effect as in the bulk case; it lowers the energy barriers for Li to diffuse outward (inward) from (to) ZnO sub-surface lattice. Our results indicate that among the three considered defects only Ovac shows possible enhancement of the kinetics of Li diffusion inside the bulk and on the surface of ZnO.

Strategy to improve Cu-BTC metal-organic frameworks performance in removal of Rhodamine B: MD and WT-MtD simulations assessment

With industry progress, environmental problems have begun to threaten human health. Among them, water pollution is closely related to human life and has attracted researchers’ attention. Hence, coping strategies for these pollutants have become a priority nowadays. Here, we carried out the molecular dynamics (MD) and well-tempered metadynamics simulations to evaluate the interaction of Rhodamine B (Rh B) with a copper (II)-benzene-1,3,5-tricarboxylate metal-organic framework (Cu-BTC/MOF). To design a more efficient dye removal platform, the effect of the -NH2, -OH, and -NO2 functional groups on the efficiency of Cu-BTC/MOF in the adsorption of Rh B is investigated. It is found that the interaction energy of Rh B with -NH2-MOF, -OH-MOF, and -NO2-MOF is about −79.98, −121.87, and −365.55 kJ mol−1, respectively, more than the pristine case. This observation confirms that the functionalization strategy can enhance the Cu-BTC/MOF efficiency. The obtained free energy (FE) values from the metadynamics simulation indicated that for adsorption of Rh B on pristine, -NH2-MOF, -OH-MOF, and -NO2-MOF, the global minimums are located about at −220.47, −234.75, −236.09, and −259.01 kJ mol−1, respectively. The obtained results show that in the two-dimensional FE surfaces, the most stable complex with Rh B belongs to the MOF-NO2 system.

Cu n Clusters (n = 13, 43, and 55) as Possible Degradant Agents of mSF6 Molecules (m = 1, 2): A DFT Study.

In order to obtain the structural and electronic properties of pristine copper clusters and Cu13–SF6, Cu43–SF6, Cu55–SF6, Cu13–2SF6, Cu43–2SF6, and Cu55–2SF6 systems, DFT calculations were carried out. For Cu13–mSF6, its surface suffers a drastic deformation, and Cu43–mSF6 at its outer surface reveals strong interaction for the first chemical molecule; when the second molecule is interacting, these outer surfaces are not severely affected. These two cases degraded fully the first SF6 molecule; however the second molecule is bonded to the latter systems and for Cu55–mSF6 (m = 1 and 2) a structural transformation from SF6 →SF4 appears as well as inner and outer shells that display slight deformations. The electronic gaps do not exhibit drastic changes after adsorption of mSF6 molecules, and the magnetic moment remains without alterations. The whole system shows thermal and vibrational stability. In addition, for Cu13–mSF6 the values of the optical gap and intensity of the optical exhibit changes with respect to the pristine case (Cu13), and the rest of the systems do not exhibit major oscillations. These icosahedral copper clusters emerge as a good option to degrade mSF6 molecules.

Effect of twin grain boundary on material thermal expansion

Based on first-principles phonon calculations within the framework of quasiharmonic approximation, we study the effect of twin grain boundary (TGB) on the thermal expansion of insulating materials. We select diamond-structure solids (C, Si, and Ge) and rutile $({\mathrm{SnO}}_{2})$ as representatives of the covalent and ionic bonding materials that are important systems commonly accompanied with TGB. We found distinct effects of TGB on thermal expansion in two types of materials. For diamond-structure solids, the thermal expansion of (111)-oriented twinning structure varies subtly from that of pristine material within the temperature range studied, which is primarily induced by the modification of vibrational phonon mode by the TGB effect. Distinctly, the thermal expansion of $\mathrm{SnO}_{2}$ twinnings increase substantially by comparison with the pristine case and depend strongly on the twin orientation. The (101) twinning shows much larger thermal expansion than the (301) twinning. Further analysis indicates the physical mechanism can be mainly attributed to the effect of rotational degree of freedom of the $\mathrm{SnO}_{6}$ octahedron motif and the stress induced by TGB. Our work reveals the physical mechanism underlying the distinct effect of TGB on thermal expansion caused by different chemical bonding, and meanwhile provides an insightful understanding of the relationship between specific structural features and thermal expansion in solid-phase materials.