Microscopic Mechanism Research Articles

The effect of moisture on the adhesion properties at the interface between asphalt and recycled aggregates

ABSTRACT The effect of moisture on the adhesion strength at the asphalt and recycled concrete aggregate (RCA) interface plays an important role in the durability performance of asphalt pavements. In this study, a universal testing machine was used to analyse the effect of moisture on the asphalt adhesion rate at the interface. Scanning electron microscopy was utilised to observe the changes in the micro-morphology of the interface before and after the effect of moisture. The effect of moisture on the interface between asphalt and recycled aggregate was investigated using molecular dynamics (MD) simulation to explore the microscopic mechanism. The results showed that the residual rate of asphalt on the surface of concrete specimens decreased from 80.2% to 34.7% after 72 h of water bath curing. The micro-morphology at the asphalt–RCA interface changed significantly before and after the action of water. Interfacial water affects the concentration distribution of asphalt components at the interface mainly by changing the nanostructure within the asphalt binder. This leads to worse adhesion properties at the asphalt–RCA interface. This study provides deeper insights into understanding water damage at the asphalt–RCA interface and provides ideas for improving the durability of the material.

Monotonic tensile and cyclic deformation of a Ni-based single crystal superalloy with anisotropic microstructural rafting patterns at high temperature: Experiment and constitutive modelling

Monotonic tensile and cyclic deformation behaviours are investigated under different microstructural rafting states of a SC Ni-based superalloy, with emphasis on the influences of the rafting extent, type and loading orientation. The deformed microstructures and the dislocation configurations are characterized to give a micro-based understanding on the varying of deformation behaviours due to rafting. It is found that the decreases in the initial yield point and cyclic stress amplitude are only related to the rafting extent. Nevertheless, the rafting type (namely, the plate-like and needle-like morphology) has an undeniable contribution to the shape of hysteresis loops, where the plate-like rafting morphology results in more significant Bauschinger effect than needle-like rafting morphology. The variation of monotonic and cyclic deformation induced by rafting shares affinity with the alteration of internal stress and the movement of dislocations. Afterwards, a microstructure-sensitive constitutive model with two-phase flow rules has been developed. The effect of rafting on the monotonic and cyclic stress-strain responses is captured by introduce a series of microscopic mechanisms and a micromechanics-based back stress model that considers the morphology and size of the γ'/γ two-phase structures. The developed model is used to simulate the macroscopic stress-strain responses of the SC Ni-based superalloy under different rafting states. Model predictions are in good agreement with tests, capturing the reduction of cyclic stress amplitudes and the change in hysteresis loops. Finally, the impacts of the two-phase flow rules and the micromechanics-based back stress on the simulation capability have been discussed.

Molecular insight on CO2/C3H8 mixed hydrate formation from the brine for sustainable hydrate-based desalination

Systematic molecular dynamics simulations have been performed to investigate the formation of CO2/C3H8 mixed hydrate in brine, to search for the optimal C3H8 content and elucidate the microscopic mechanism for hydrate-based desalination process. Simulation results indicate that the desalination process is significantly affected by the formation kinetics of CO2/C3H8 mixed hydrates due to the diverse physical properties of CO2 and C3H8 molecules in the brine. Specifically, CO2 molecules are more likely to leave the mixed gas nanobubbles and form hydrates, whereas most of C3H8 molecules remain in gas nanobubbles for a prolonged period. Interestingly, ions can form abnormal CO2-occupied and C3H8-occupied hydrate cages by replacing the water molecule in cages, and some ions can also be adsorbed on the surfaces of the cage-like hydrogen bond network or encapsulated between the hydrate solids. The presence of these ions presents a challenge to separating them due to the strong attraction from the water in hydrate solids. On the other hand, it is confirmed that the C3H8 content with 10 % is optimal for CO2/C3H8 mixed hydrate-based desalination, as it promotes the decomposition of mixed gas nanobubbles to form hydrates by suppressing the structural fluctuations in the system. These molecular insights into the effect of C3H8 content on CO2/C3H8 mixed hydrate formation in brine may help to develop hydrate-based desalination technology.

First-Order Rhombohedral-to-Cubic Phase Transition in Photoexcited GeTe.

Photoexcited GeTe undergoes a nonthermal phase transition from a rhombohedral to a rocksalt crystalline phase. The microscopic mechanism and the nature of the transition are unclear. By using constrained density functional perturbation theory and by accounting for quantum anharmonicity within the stochastic self-consistent harmonic approximation, we show that the nonthermal phase transition is strongly first order and does not involve phonon softening, at odds with the thermal one. The transition is driven by the closure of the single particle gap in the photoexcited rhombohedral phase. Finally, we show that ultrafast x-ray diffraction data are consistent with a coexistence of the two phases, as expected in a first order transition. Our results are relevant for the understanding of phase transitions and bonding in phase change materials.

Microscopic mechanism of ultrasonically welded joints: The role of terminal roughness and wire diameter

The ultrasonic welding technology is widely promoted as a new connection approach in the field of current energy vehicle wiring harness connection. In this paper, three kinds of 25mm2 copper wire harnesses with different wire diameters and T2 copper terminals with different surface roughness were welded by ultrasonic welding. The mechanical properties of the joints were investigated by tensile experiments and the microstructure of joints was characterised using SEM and EBSD techniques. Excessive roughness increases plastic deformation at the weld interface during ultrasonic welding. This increases the dislocation density at the weld interface and refines the grain size. However, at the same time it inhibits recrystallisation to a certain extent. The lower roughness facilitates recrystallisation, but the low density of HAGBs makes the interface susceptible to slip in extended crystallographic plane and direction. Appropriate roughness allows the weld interface to generate fine equiaxed grains and a high density of HAGBs. This facilitates the obstruction of dislocation movement and improves the strength of joint. In addition, the high porosity of a longitudinal cross-section of the conductor with its small diameter was investigated. This results in a large number of wires remaining on the terminals when force is applied. It was determined that the larger a diameter of wire, the higher a cross-sectional porosity. The copper wire breaks at a weak point in cross-section when the force is applied, resulting in the entire wire being left on terminal. At a wire diameter of 0.2 mm, the porosity of a cross-section reaches an equilibrium and the strength of joint is even higher than the strength of material itself, resulting in the joint pulling off. The maximum strength reaches 4703.77 N.

On the Origin of the Above-Room-Temperature Magnetism in the 2D van der Waals Ferromagnet Fe3GaTe2.

2D magnetic materials have attracted growing interest driven by their unique properties and potential applications. However, the scarcity of systems exhibiting magnetism at room temperature has limited their practical implementation into functional devices. Here we focus on the van der Waals ferromagnet Fe3GaTe2, which exhibits above-room-temperature magnetism (Tc = 350-380 K) and strong perpendicular anisotropy. Through first-principles calculations, we examine the magnetic properties of Fe3GaTe2 and compare them with those of Fe3GeTe2. Our calculations unveil the microscopic mechanisms governing their magnetic behavior, emphasizing the pivotal role of ferromagnetic in-plane couplings in the stabilization of the elevated Tc in Fe3GaTe2. Additionally, we predict the stability, substantial perpendicular anisotropy, and high Tc of the single-layer Fe3GaTe2. We also demonstrate the potential of strain engineering and electrostatic doping to modulate its magnetic properties. Our results incentivize the isolation of the monolayer and pave the way for the future optimization of Fe3GaTe2 in magnetic and spintronic nanodevices.

Beyond the Charge Transfer Mechanism for 2D Materials-Assisted Surface Enhanced Raman Scattering.

Two-dimensional (2D) materials have been extensively implemented as surface-enhanced Raman scattering (SERS) substrates, enabling trace-molecule detection for broad applications. However, the accurate understanding of the mechanism remains elusive because most theoretical explanations are still phenomenological or qualitative based on simplified models and rough assumptions. To advance the development of 2D material-assisted SERS, it is vital to attain a comprehensive understanding of the enhancement mechanism and a quantitative assessment of the enhancement performance. Here, the microscopic chemical mechanism of 2D material-assisted SERS is quantitatively investigated. The frequency-dependent Raman scattering cross sections suggest that the 2D materials' SERS performance is strongly dependent on the excitation wavelengths and the molecule types. By analysis of the microscopic Raman scattering processes, the comprehensive contributions of SERS can be revealed. Beyond the widely postulated charge transfer mechanisms, the quantitative results conclusively demonstrate that the resonant transitions within 2D materials alone are also capable of enhancing the molecular Raman scattering through the diffusive scattering of phonons. Furthermore, all of these scattering routines will interfere with each other and determine the final SERS performance. Our results not only provide a complete picture of the SERS mechanisms but also demonstrate a systematic and quantitative approach to theoretically understand, predict, and promote the 2D materials SERS toward analytical applications.

Multiaxial creep–fatigue failure mechanism and life prediction of a turbine blade based on a unified numerical solution approach

AbstractExposure of turbine blades to cyclic torsional loading at high temperature, stemming from pre‐torque installation and the aerodynamic forces during operation, has the potential to induce substantial creep–fatigue damage, thereby contributing to the likelihood of premature failure. Investigating the deformation mechanisms and proposing a reliable life prediction method aiming at torsional loading is critical to ensure the structural integrity of turbine blades. This study conducted strain‐controlled fatigue and creep–fatigue tests on Inconel 718 superalloy, employing a multiaxial servo‐hydraulic testing machine. Electron backscattering diffraction elucidated deformation and damage mechanisms, forming a basis for subsequent constitutive modeling and life prediction. The lack of creep–fatigue mechanical behavior and microscopic failure mechanism when stress triaxiality equal to 0 is filled, which provides the theoretical basis and data support for the life design and damage assessment of this material under extreme service conditions. The unified viscoplasticity constitutive model effectively characterized macroscopic deformation under torsional loading. Prediction of creep–fatigue life under torsional loading, utilizing the multiaxial ductility factor‐modified strain energy density exhaustion model, demonstrated excellent alignment with experimental findings. Finally, parametric analyses of stress distribution and damage assessment under different conditions were carried out for the example of a turbine blade with relatively rarely considered aerodynamic loading as a variable. It is expected to be popularized and applied in life design and damage assessment of high‐temperature structures under multiaxial loading in engineering.

Gamma‐Ray‐Induced Photoelectric Field Exacerbating Irradiation Damage in Ceramic Capacitors

Ceramic capacitors are widely used in radioactive environments and are known to take irradiation damages, but most of previous studies of its reliability focus on thermal or electrical issues, and much less is known about the microscopic mechanism of its irradiation damaging process. Herein, it is shown that the capacitance of ceramic capacitors can change significantly under continuous gamma‐ray irradiation. Moreover, it is noticed that ex situ measurements will underestimate the effect comparing with the in situ one. Herein, it is discovered that this difference is due to the gamma‐ray‐induced photoelectric field, which dissipate rapidly in ex situ measurements. While the impact of the photoelectric field on the capacitance can be seen in situ, due to the recombination of photogenerated carriers and annealing of defects after irradiation, ex situ measurements only account for a part of the irradiation damage. This discovery indicates that ex situ measurements, which are prevailing in irradiation damage studies, can miss critical information, and in situ measurements are necessary for revealing the mechanism of the process.

A deformation twin mediated sliding-opening zig-zag fracture mechanism in multi-principal element alloys

Multi-principal element alloys (MPEA) have emerged as a class of high-performance materials. Of particular interest is the excellent fracture toughness in face-centered cubic MPEAs with low stacking fault energy, where abundant deformation twins are commonly observed. To understand the fracture mechanism in such MPEAs, here we perform in situ nanomechanical testing inside transmission electron microscope, atomistic simulation, and theoretical analysis to investigate the mechanism of interaction between a propagating crack and a coherent twin boundary (TB) in CoCrFeNi MPEA. We unveil a hitherto unknown microscopic mechanism of crack-TB interaction in MPEAs, where sliding along secondary nanotwins (NTs) nucleated from the primary TB followed by sub-crack nucleation some distance ahead of the main crack constitute a consecutive sliding-opening crack propagation mechanism, leading to zig-zag fracture around the primary TB. The origin of this mechanism lies in the frequent nucleation of NTs from steps on the primary TB, which can effectively blunt and deflect a propagating crack. Quantitative analysis indicates nearly doubled fracture resistance associated with this unique mechanism of crack-TB interaction in MPEAs. These findings bring about a missing aspect in TB-modulated fracture in MPEAs and enrich our understanding of the enhanced damage tolerance of alloys with low stacking fault energy.

Mn loading on montmorillonite surfaces for Cd stabilization: Insights from density functional theory calculations and surface complexation modeling

The latest works have been devoted to the stabilization mensuration for heavy metals and indicate that clay minerals can promote Cd(II) precipitation by favoring the retention of Mn(II). The assessment however has been tempered due to lacking the information about the molecular-level surface complexation structure and Cd nucleation process on clay surfaces. In this study, microscopic mechanisms for adsorption and stabilization of Cd at montmorillonite interfaces with or without Mn loading were leveraged by combining surface complexation model (SCM) evaluations and density functional theory (DFT) calculations. Mn(II) substitution resulted in increases in surface acidity equilibrium constant (pKa) by about 1 unit and complexation constant (lgK(SOCd+)) of Cd(II) by about 0.15 units at clay surface, and Mn(II) adion can provide extra active sites (i.e., OH− groups) for complexing Cd(II) via hydrolysis. DFT calculations revealed Mn(II) and Cd(II) adions bind on base surfaces by isomorphic substitutions through weak long-range interactions, whereas on edge surfaces by surface complexation with strong but short-range connections. Adsorption energy calculations and electrostatic distribution showed heterogenous nucleation with subsequent cations on clay surfaces was thermodynamically favored, the stabilization process underwent the steps of the adsorption-hydrolysis-precipitation. The derived results provide a quantitative basis for understanding the precipitation and heterogenous nucleation of cations on clay surfaces in surficial environments.

Particle breakage of calcareous sand from low-high strain rates

The influence of strain rate on the mechanics of particles is well documented. However, a comprehensive understanding of the strain rate effect on calcareous particles, particularly in the transition from static to dynamic loading, is still lacking in current literature. This study conducted 720 quasi-static and impact tests on irregular calcareous particles to investigate the macroscopic strain rate effect, and performed numerical simulations on spherical particles to explore the underlying microscopic mechanisms. The strain rate effect on the characteristic particle strength was found to exhibit three regimes: in Regime 1, the particle strength gradually improves when the strain rate is lower than approximately 102 s−1; in Regime 2, the particle strength sharply enhances when the strain rate increases from 102 s−1 to 104 s−1; and in Regime 3, the particle strength remains almost constant when the strain rate is higher than 104 s−1. The three-regime strain rate effect is an inherent property of the material and independent of particle shape. The asynchrony between loading and deformation plays a dominant role in these behaviors, leading to a thermoactivation-dominated effect in Regime 1, a macroscopic viscosity-dominated effect in Regime 2, and a combined thermoactivation and macroscopic viscosity-dominated effect in Regime 3. These mechanisms induce a transition in the failure mode from splitting to exploding and then smashing, which increases the energy required to rupture a single bond and, consequently, enhances the particle strength.

Dielectric loss due to charged-defect acoustic phonon emission

The coherence times of state-of-the-art superconducting qubits are limited by bulk dielectric loss, yet the microscopic mechanism leading to this loss is unclear. Here, we propose that the experimentally observed loss can be attributed to the presence of charged defects that enable the absorption of electromagnetic radiation by the emission of acoustic phonons. Our explicit derivation of the absorption coefficient for this mechanism allows us to derive a loss tangent of 7.2 × 10−9 for Al2O3, in good agreement with recent high-precision measurements [Read et al., Phys. Rev. Appl. 19, 034064 (2023)]. We also find that for temperatures well below ∼0.2 K, the loss should be independent of temperature, which is also in agreement with observations. Our investigations show that the loss per defect depends mainly on properties of the host material, and a high-throughput search suggests that diamond, cubic BN, AlN, and SiC are optimal in this respect.

Insight into selectivity of photocatalytic methane oxidation to formaldehyde on tungsten trioxide

Tungsten trioxide (WO3) has been recognized as the most promising photocatalyst for highly selective oxidation of methane (CH4) to formaldehyde (HCHO), but the origin of catalytic activity and the reaction manner remain controversial. Here, we take {001} and {110} facets dominated WO3 as the model photocatalysts. Distinctly, {001} facet can readily achieve 100% selectivity of HCHO via the active site mechanism whereas {110} facet hardly guarantees a high selectivity of HCHO along with many intermediate products via the radical way. In situ diffuse reflectance infrared Fourier transform spectroscopy, electron paramagnetic resonance and theoretical calculations confirm that the competitive chemical adsorption between CH4 and H2O and the different CH4 activation routes on WO3 surface are responsible for diverse CH4 oxidation pathways. The microscopic mechanism elucidation provides the guidance for designing high performance photocatalysts for selective CH4 oxidation.

Competitive adsorption of CH4/CO2 in shale nanopores during static and displacement process

During the development of shale gas, various issues such as low individual well production, rapid decline, limited reservoir control, and low recovery rates have arisen. Enhancing shale gas reservoir recovery rates has consistently been a focal point and challenge within the industry. Therefore, this paper employs molecular dynamic (MD) simulation methods to study the adsorption and diffusion characteristics of CH4/CO2 at different temperatures and mixing ratios. It compares the effects of temperature and CH4/CO2 molar ratio changes on the selectivity coefficient, adsorption capacity, and diffusion coefficient of CH4/CO2. The paper also plots the displacement interface and the function of CH4/CO2 injection/residual amounts over time. Furthermore, it analyzes the adsorption capacity of molecules on the graphene surface, the migration capacity of molecules in the slit, and the displacement process of CH4 by CO2 on the nanoscale, revealing the microscopic mechanism of CH4/CO2 competitive adsorption and displacement. The research results indicate that the influence of temperature on the selectivity coefficient is not significant, with an average decrease of 3% for every 20 K rise in temperature. Pressure has a more pronounced effect on the selectivity coefficient, with values around 1.4 at low pressures and around 1.2 at high pressures. Elevating the mole fraction of CO2 in the binary gas mixture results in an increase in the total adsorption amount and an accelerated variation of adsorption amount with pressure. As the CH4 mole fraction rises, the diffusion coefficient of CH4 increases, while the diffusion coefficient of CO2 diminishes with an increasing CO2 mole fraction. Under identical conditions, CO2 exhibits a stronger adsorption capacity over CH4 in shale organic nanopores, resulting in a concave moon-shaped displacement interface in the model. The larger the pre-adsorption pressure of CO2, the more intense the movement of CO2 along the graphene surface, and the faster the diffusion speed of CO2 along the wall. In a displacement pore (the pore space used to provide the displacement location or site) with a diameter of 3 nm, at smaller pressure differentials (≤10 MPa), the residual amount of CH4 remains relatively stable without substantial alteration. However, at a pressure differential of 20 MPa, the residual amount of CH4 decreases rapidly, and the displacement efficiency significantly improves.

Nanoscale insight into the reconstruction reaction mechanism of alkali-activated silicate materials

As a green alternative to cement-based materials, alkali-activated silicate materials (AASM) have garnered attention for their ability to reduce greenhouse gas emissions and efficiently utilize industrial waste. During AASM preparation, Si monomers such as [SiO2(OH)2]2-, [SiO(OH)3]-, Si(OH)4 play a crucial role in governing the formation rate and unique gel structure of AASM. Despite their widespread use in construction, the microscopic mechanism of Si monomer formation from reactive SiO2 groups via reconstruction reactions (RR) remains unclear. This study comprehensively explored the structural transformations, formation pathways, and electron transfer mechanisms of Si monomers in AASM gels during RR using molecular dynamics (MD) simulations and first-principles calculations. We identified six distinct formation pathways for three Si monomers, with SiO2 → SiO2H2O → SiO2(H2O)2 → SiO(OH)2H2O exhibiting the highest energy barrier of 16.61kJ/mol. Further analysis revealed a correlation between energy barriers and orbital hybridization strength, providing new insights into Si monomer formation mechanisms in AASM. This lays a solid foundation for optimizing AASM's preparation and enhancing its performance, further promoting the environmental friendliness and efficient utilization of AASM.

Adsorption of monoclonal antibody fragments at the water-oil interface: A coarse-grained molecular dynamics study.

Monoclonal antibodies (mAbs) can undergo structural changes due to interaction with oil-water interfaces during storage. Such changes can lead to aggregation, resulting in a loss of therapeutic efficacy. Therefore, understanding the microscopic mechanism controlling mAb adsorption is crucial to developing strategies that can minimize the impact of interfaces on the therapeutic properties of mAbs. In this study, we used MARTINI coarse-grained molecular dynamics simulations to investigate the adsorption of the Fab and Fc domains of the monoclonal antibody COE3 at the oil-water interface. Our aim was to determine the regions on the protein surface that drive mAb adsorption. We also investigate the role of protein concentration on protein orientation and protrusion to the oil phase. While our structural analyses compare favorably with recent neutron reflectivity measurements, we observe some differences. Unlike the monolayer at the interface predicted by neutron reflectivity experiments, our simulations indicate the presence of a secondary diffused layer near the interface. We also find that under certain conditions, protein-oil interaction can lead to a considerable distortion in the protein structure, resulting in enhanced adsorption behavior.

Effects of Salt Content and Freeze-Thaw Conditions on Dynamic characteristics and its microscopic mechanism of Chloride Silty Clay

Generally, artificial ground freezing (AGF) technology is utilized to guarantee tunnel safety during construction. However, the soil structure changes significantly after freeze-thaw, resulting in uneven deformation of the tunnel under traffic loading from subway vibration. To solve this problem effectively, it is necessary to consider the combined impact of freeze-thaw, salt, and traffic loading damage that marine soft soil must withstand simultaneously. For this reason, cyclic triaxial test and NMR test were performed on the silty clay saturated with NaCl solution in this study. The influence of three main factors on dynamic properties has been thoroughly investigated, namely freeze-thaw, salt content, and confining pressure. According to cyclic triaxial test, the shape of the hysteresis loop of the specimens after freeze-thaw changed more significantly with increasing loading cycles. The dynamic elastic modulus was weakened by freeze-thaw, while improved by the addition of NaCl. Damping ratio was consistent with the dynamic elastic modulus law. It was worth noting that the different freezing temperatures (−10 °C, −20 °C and − 30 °C) had only a slight impact on dynamic elastic modulus, as well as damping ratio. Mathematical models were proposed to forecast the dynamic elastic modulus and damping ratio regarding marine soft clay. NMR test indicated that the addition of salt made the internal pore environment of the specimens tend to be consistent and enhanced the water-solid interaction. The increase in porosity resulted in the decrease in dynamic elastic modulus. The results have provided valuable insights into the mechanical characteristics of marine soft clay when AGF technology is applied.

Nanoscale Investigation of the Effect of Annealing Temperature on the Polarization Switching Dynamics of Hf0.5Zr0.5O2 Thin Films

AbstractRecently, HfO2‐based ferroelectric thin films have attracted widespread interest in developing next‐generation nonvolatile memories. To form a metastable ferroelectric orthorhombic phase in HfO2, a post‐annealing process is typically necessary. However, the microscopic mechanism underlying the effect of annealing temperature on ferroelectric domain nucleation and growth is still obscure, despite its importance in optimizing the operation speed of HfO2‐based devices. In this study, the ferroelectric properties and polarization switching of Hf0.5Zr0.5O2 thin films annealed at different temperatures (550–700 °C) are systematically investigated. Evidently, the crystal structure, remnant polarization, and dielectric constant monotonically change with annealing temperature. However, microscopic piezoresponse force microscopy images as well as macroscopic switching current measurements reveal non‐monotonic changes in the polarization switching speed with annealing temperature. This intriguing behavior is ascribed to the difference in the ferroelectric‐domain nucleation process induced by the amount of oxygen vacancies in the Hf0.5Zr0.5O2 thin films annealed at different temperatures. This work demonstrates that controlling the defect concentration of ferroelectric HfO2 by tuning the post‐annealing process is critical for optimizing device performance, particularly polarization switching speed.

Spatiotemporal Evolution and Frontier Focus Analysis Based on Coal Fire Control Body of Knowledge

Mine fire accidents frequently constitute a major threat to mining safety, and their potential consequences are extremely severe, which highlights the urgency of fire prevention and control research. In this study, the CiteSpace software was used to conduct a metrological analysis of 717 relevant studies in the field of mine fire prevention and control (MFPC), aiming to reveal the research trends and trends in this field. This analysis found that the annual number of MFPC articles showed a significant upward trend, indicating that it is in rapid development during the active period. China, the United States, and Australia are the main contributors in this field, and the institutional contribution of China University of Mining and Technology is particularly outstanding, reflecting the regional concentration of research activities. The analysis of cooperation networks reveals the close cross-regional collaboration among European countries. The inhibition effect and evaluation criteria and the inhibition technology under different coal characteristics have become the focus of research. Activation energy, release, and quantum chemistry have become recent hot spots, reflecting the research on the mechanism of forward physicochemical synergistic inhibition and the in-depth exploration of the molecular level. It indicates that future research will focus on the development of temperature-responsive retardant materials, the application of quantum chemistry theory, and the exploration of the microscopic mechanism of coal spontaneous combustion through molecular simulation technology to further optimize the fire prevention strategy. In summary, the findings of this study not only provide a comprehensive picture of current research activities in the MFPC field but also indicate potential directions for future research and have important guiding significance for promoting the development of this field.