Film Coefficient Research Articles

Fabrication and Tribological Properties of Diamond-like Carbon Film with Cr Doping by High-Power Impulse Magnetron Sputtering

The present study aims to investigate the advantages of diamond-like carbon (DLC) films in reducing friction and lubrication to address issues such as the low surface hardness, high friction coefficients, and poor wear resistance of titanium alloys. Cr-doped DLC films were deposited by high-power impulse magnetron sputtering (HiPIMS) in an atmosphere of a gas mixture of Ar and C2H2. The energy of the deposited particles was controlled by adjusting the target powers, and four sets of film samples with different powers (4 kW, 8 kW, 12 kW, and 16 kW) were fabricated. The results showed that with an increase in target power, the Cr content increased from 3.73 at. % to 22.65 at. %; meanwhile, the microstructure of the film evolved from an amorphous feature to a nanocomposite structure, with carbide embedded in an amorphous carbon matrix. The sp2-C bond content was also increased in films, suggesting an intensification of the film’s graphitization. The hardness of films exhibited a trend of initially increasing and then decreasing, reaching the maximum value at 12 kW. The friction coefficient and wear rate of films showed a reverse trend compared to hardness variation, namely initially decreasing and then increasing. The friction coefficient reached a minimum value of 0.14, and the wear rate was 2.50 × 10−7 (mm3)/(N·m), at 8 kW. The abrasive wear was the primary wear mechanism for films deposited at a higher target power. Therefore, by adjusting the target power parameter, it is possible to control the content of the metal and sp2/sp3 bonds in metal-doped DLC films, thereby regulating the mechanical and tribological properties of the films and providing an effective approach for addressing surface issues in titanium alloys.

Enhancement of the photothermoelectric effect through synergistic modulation of multiple parameters

The performance of photothermoelectric materials is severely limited by various intrinsic parameters that are difficult to simultaneously modulate, thereby hindering their applications in the fields of photodetectors, solar cells, thermoelectric therapy and so on. In this study, we have prepared suspended films composed of carbon nanotube (CNT) and molybdenum disulfide quantum dots (MoS2 QDs), which demonstrate a remarkable maximum photothermal conversion efficiency of 2201 K·mm2·W−1. This outstanding performance is attributed to the formation of a heterojunction between CNT and MoS2 QDs. Furthermore, the light absorption, temperature coefficient of resistance, and Seebeck coefficient of this suspended film are simultaneously modulated in a direction conducive to enhancing the photothermoelectric effect. Consequently, we have fabricated CNT-CNT/MoS2 QDs p-n junction photodetectors to showcase the improved photoresponse performance. This study presents an innovative approach for modulating multiple intrinsic parameters of photothermoelectric materials, which offers valuable insights for enhancing the performance of corresponding photothermoelectric devices.

Influence of Grain Size and Film Formation Potential on the Diffusivity of Point Defects in the Passive Film of Pure Aluminum in NaCl Solution

The influence of grain size on the corrosion behavior of pure aluminum and the defect density and diffusion coefficient of surface passive films were investigated using electron backscatter diffraction (EBSD) and electrochemical testing techniques, based on the point defect model (PDM). Samples with three different grain sizes (23 ± 11, 134 ± 52, and 462 ± 203 μm) were obtained by annealing at different temperatures and times. The polarization curves and electrochemical impedance spectroscopy results for the pure aluminum in the 3.5% NaCl solution showed that with decreasing grain size, the corrosion current (icorr) decreased monotonously, giving rise to a noble corrosion potential and a large polarization resistance. The Motte–Schottky results showed that the passive films that formed on pure aluminum with fine grains of 23 ± 11 μm had a low density (3.82 × 1020 cm−3) of point defects, such as oxygen vacancies and/or metal interstitials, and a small diffusion coefficient (1.94 × 10−17 cm2/s). The influence of grain size on corrosion resistance was discussed. This work demonstrated that grain refinement could be an effective approach to achieving high corrosion resistance of passive metals.

2D Graphene Oxide: A Versatile Thermo‐Optic Material

AbstractEfficient heat management and control in optical devices, facilitated by advanced thermo‐optic materials, are critical for many applications such as photovoltaics, thermal emitters, mode‐locked lasers, and optical switches. Here, a range of thermo‐optic properties of 2D graphene oxide (GO) films are investigated by precisely integrating them onto microring resonators (MRRs) with control over the film thicknesses and lengths. The refractive index, extinction coefficient, thermo‐optic coefficient, and thermal conductivity for the GO films with different layer numbers and degrees of reduction, as well as reversible reduction and enhanced optical bistability induced by the photo‐thermal effects, are comprehensively characterized. Experimental results show that the thermo‐optic properties of 2D GO films vary widely with the degree of reduction. In addition, significant anisotropy is observed for the thermo‐optic response, enabling efficient polarization‐sensitive devices. The versatile thermo‐optic response of 2D GO substantially expands the scope of functionalities and devices that can be engineered, making it promising for a diverse range of thermo‐optic applications.

Structural and optical properties of Cu2ZnSnSe4 nanocrystals thin film

In this paper, we analyzed the structural and optical properties of quaternary semiconductor Cu2ZnSnSe4 (CZTSe) thin film. For this purpose, the structural properties of CZTSe thin film were analyzed using X-ray diffraction (XRD) and transmission electron microscopy (TEM). CZTSe nanocrystals (NCs) were formed in the kesterite phase and with good crystallinity. Optical characterization of thin film was investigated using spectroscopic measurements. Optical parameters of CZTSe film coated using the spin coating technique were determined by UV-Vis-NIR spectroscopy. The refractive index, extinction coefficient, and dielectric constant of the thin film were calculated using transmittance and reflectance data. Moreover, dispersion parameters such as oscillator energy, and dispersion energy were obtained by the Wemple DiDomenico model. For CZTSe film in the visible wavelength region, the transmission has values of 70–75%. The thin film of CZTSe has a direct band gap of 1.4 eV which is suitable for absorbed layer for solar cell.

Piezoelectric Charge Coefficient of Halide Perovskites.

Halide perovskites are an emerging family of piezoelectric and ferroelectric materials. These materials can exist in bulk, single-crystal, and thin-film forms. In this article, we review the piezoelectric charge coefficient (dij) of single crystals, thin films, and dimension-tuned halide perovskites based on different measurement methods. Our study finds that the (dij) coefficient of the bulk and single-crystal samples is mainly measured using the quasi-static (Berlincourt) method, though the piezoforce microscopy (PFM) method is also heavily used. In the case of thin-film samples, the (dij) coefficient is dominantly measured by the PFM technique. The reported values of dij coefficients of halide perovskites are comparable and even better in some cases compared to existing materials such as PZT and PVDF. Finally, we discuss the promising emergence of quasi-static methods for thin-film samples as well.

Realizing the giant seebeck coefficient and electrical conductivity in SnTe thin films by grain engineering

In this work, we have modulated the film growth parameter (post growth annealing) of SnTe-based thin films to enhance the charge carrier transport by controlling the morphology and microstructure. The samples under investigation were prepared by a vacuum tube furnace on a glass substrate using following growth conditions; growth temperature 700 °C, pressure in the tube 180 mTorr, source to substrate distance 7 cm. Grain engineering was performed by annealing the samples at different temperatures (200–500 °C) which was used as a powerful tool to enhance the mobility of charge carriers (7–13 cm2/V-Sec). SEM images demonstrated that a representative sample annealed at 300 °C has a layered structure, therefore the carriers in this sample possessed the highest value of mobility. This encouraging value of carrier mobility resulted in the enhancement of the Seebeck coefficient (7600 μV/K) and electrical conductivity (5S/cm) simultaneously. XRD and Raman spectroscopy measurements were also performed to crystal structure and vibrational modes of annealed SnTe thin films. In conclusion, it is reported that the annealing temperature of 300 °C is supposed to be the optimal value for required grain engineering in order to realize the highest value of the Seebeck coefficient and electrical conductivity.

High output flexible polyvinylidene fluoride based piezoelectric device incorporating cellulose nanofibers/BaTiO3@TiO2 piezoelectric core-shell structure

Flexible composite film has gained increasing attention in the fields of wearable devices and portable electronic products. In this work, a novel core-shell structure of cellulose nanofibers/BaTiO3@TiO2 (CNF/BTO@TiO2) was synthesized with the assistant of the biological macromolecule material of cellulose nanofiber (CNF), in which the CNF can improve the stability and dispersibility of BaTiO3 (BTO) in the aqueous phase and elevate the integrity of the core-shell structure. The core-shell structure can reduce the agglomeration of fillers in polyvinylidene fluoride (PVDF) and improve the structural defects of the composite film. Meanwhile, the core-shell structure can promote the polarization of the electric dipole and the formation of β phase in PVDF due to the generated interface spatial polarization between the shell of TiO2 and the core of BTO. When the content of the core-shell structure was 5 wt%, the β phase content reaches 61.89 %, and the piezoelectric coefficient of composite film reaches 84.29 pm/V. Thus the maximum output open-circuit voltage (VOC) and short-circuit current (ISC) of the piezoelectric composite film is as high as 13.10 V and 464.3 nA. In addition, its excellent pressure sensing capability allows for its application in various flexible electronic devices.

Optical Properties of Gallium Nitride Heterostructures Grown on Quartz Using Pulse Laser Deposition Method

An optical analysis was conducted on a Gallium nitride (GaN) thin film grown on a quartz substrate using the physical vapor deposition technique (PVD), specifically, pulsed laser deposition (PLD). The film was grown using different laser wavelengths (1064, 532, and 355) nm from a Q-switch neodymium-doped yttrium aluminum garnet (Nd: YAG) laser, all performed under a vacuum pressure of 10-2 m bar. The absorption coefficient of the GaN thin film was determined by performing UV-Vis diffused spectroscopy at room temperature and measuring wavelengths ranging from 200 to 1000 nm. The absorption peak occurs at 227 nm when the wavelength is 1064 nm, at 217 nm when the wavelength is 532 nm, and at 222 nm when the wavelength is 355 nm. The optical energy gap is a crucial statistic for analyzing the properties of thin films and assessing their potential as gas sensors. The value of the direct energy gap (Eg) for the prepared films was established by analyzing the graph that shows the relationship between (α h) and the energy gap (ev) values at different wavelengths. The energy values were determined to be 3.36 eV, 3.62 eV, and 3.7 eV for 1064, 532, and 355 nm wavelengths, respectively.

Interface engineering and heterometal doping Cu3Se2/WSe2 for efficient charge transfer and nonlinear optical performance

Integrating interface engineering and precious heterometal doping with semiconductors is a feasible pathway to construct efficient charge transfer and improve the nonlinear optical (NLO) performance of materials. Here, we report a bimetallic selenide type-II heterostructure of Cu3Se2/WSe2 (CWS) with a simple one-step magnetron co-sputtering of Cu and WSe2 targets at low argon flow rates. Se first nucleates and precipitates to form nanospheres at low flow rates. Due to the electronegativity of Cu being greater than that of W and Cu prioritizes attachment to the outside of the Se nanospheres and promotes the formation of the nanorods-grown Cu3Se2. A combined analysis of X-ray photoelectron spectroscopy and X-ray diffraction data was used to investigate the minor shift in the W 4 f/Se 2p ratio revealing that electrons shifted from Cu3Se2 to WSe2. The diffraction peaks of CWS and the valence electronic structure of Cu1+/Cu2+ confirmed the implantation of Cu3Se2 nanorods on WSe2. The NLO properties of CWS composite films were modulated by varying the power of Cu. More importantly, the nonlinear absorption coefficient of the CWS composite films formed after Cu3Se2 promotion is much better than that of other unmodified pure WSe2 films. The photogenerated carrier dynamics of CWS composite films were investigated by femtosecond transient absorption spectroscopy, and density functional theory calculations show that CWS composite films inhibit efficient electron transfer photogenerated carrier complexation. This work proposes a few strategies for designing heterogeneous structures with interface engineering and precious metal doping to promote adjustable electron transfer dynamics and achieve high NLO conversion efficiency.

Effects of Laser Treatment of Terbium-Doped Indium Oxide Thin Films and Transistors.

In this study, a KrF excimer laser with a high-absorption coefficient in metal oxide films and a wavelength of 248 nm was selected for the post-processing of a film and metal oxide thin film transistor (MOTFT). Due to the poor negative bias illumination stress (NBIS) stability of indium gallium zinc oxide thin film transistor (IGZO-TFT) devices, terbium-doped Tb:In2O3 material was selected as the target of this study. The XPS test revealed the presence of both Tb3+ and Tb4+ ions in the Tb:In2O3 film. It was hypothesized that the peak of the laser thermal effect was reduced and the action time was prolonged by the f-f jump of Tb3+ ions and the C-T jump of Tb4+ ions during the laser treatment. Studies related to the treatment of Tb:In2O3 films with different laser energy densities have been carried out. It is shown that as the laser energy density increases, the film density increases, the thickness decreases, the carrier concentration increases, and the optical band gap widens. Terbium has a low electronegativity (1.1 eV) and a high Tb-O dissociation energy (707 kJ/mol), which brings about a large lattice distortion. The Tb:In2O3 films did not show significant crystallization even under laser energy density treatment of up to 250 mJ/cm2. Compared with pure In2O3-TFT, the doping of Tb ions effectively reduces the off-state current (1.16 × 10-11 A vs. 1.66 × 10-12 A), improves the switching current ratio (1.63 × 106 vs. 1.34 × 107) and improves the NBIS stability (ΔVON = -10.4 V vs. 6.4 V) and positive bias illumination stress (PBIS) stability (ΔVON = 8 V vs. 1.6 V).

Enhancing the Responsiveness of Thermoelectric Gas Sensors with Boron-Doped and Thermally Annealed SiGe Thin Films via Low-Pressure Chemical Vapor Deposition.

Thermoelectric gas sensor (THGS) devices with catalysts and Si0.8Ge0.2 thin films of different boron doping levels of 1018, 1019, and 1020 cm-3 were fabricated, and their transport properties are investigated. SiGe films were deposited on Si3N4/SiO2 multilayers on Si substrates using low-pressure chemical vapor deposition (LPCVD) and thermally annealed at 1050 °C. The Seebeck coefficients of the SiGe films were increased after thermal annealing, ranging from 191 to 275 μV/K at temperatures of 74 to 468 °C in air, and reaching the highest power factor of 6.78 × 10-4 W/mK2 at 468 °C. The thermal conductivity of the SiGe films varied from 2.4 to 3.0 W/mK at 25 °C. The THGS detection performance was tested for the H2 gas in air from 0.01 to 1.0%, and compared to the thermoelectric properties of the SiGe films. The high-temperature annealing treatment process was successful in enhancing the thermoelectric performance of both the SiGe films and sensor devices, achieving the best THGS performance with the sensor device fabricated from the annealed SiGe film with 1018 cm-3 boron-doped Si0.8Ge0.2.

What Determines the Low-Friction Mechanism of the Silicon-Doped Diamond-like Carbon Film in a Water Environment: An Atomic-Level Understanding.

It is widely acknowledged that doping silicon can significantly enhance the friction performance of diamond-like carbon (DLC) films in a water environment. However, the mechanism of low friction caused by doped silicon is still highly controversial. Therefore, this article compares the interface interaction between DLC and Si-DLC films in a water environment through first-principles calculations of physisorption and chemisorption effects. The results indicate that water molecules are predominantly chemically adsorbed rather than physically adsorbed on the Si-DLC surface. Further study reveals that when OH-termination is formed on the Si-DLC surface, water molecules are predominantly physically adsorbed rather than chemically adsorbed on the Si-DLC hydroxylation surface. Consequently, a more stable hydration layer is formed on the surface through the hydrogen bond network formed by Si-OH groups, ultimately leading to lower friction. Moreover, molecular dynamics simulations further suggest that the lower friction coefficient of Si-DLC films in a water environment may be due to more water molecules at the friction interface and fewer interface covalent bonds. In short, the low-friction coefficient of the Si-DLC film in a water environment may be caused not only by the chemisorption of water molecules on its surface but also by the physisorption of water molecules on the Si-DLC film after surface hydroxylation.

High-Performance W-Doped Bi0.5Sb1.5Te3 Flexible Thermoelectric Films and Generators.

Bi-Sb-Te-based thermoelectric materials have the best room-temperature thermoelectric properties, but their inherent brittleness and rigidity limit their application in the wearable field. In this study, W-doped p-type Bi0.5Sb1.5Te3 (W-BST) thin films were prepared using magnetron sputtering on polyimide substrates to create thermoelectric generators (TEGs). Bending tests showed that the thin film has excellent flexibility and mechanical durability, meeting the flexible requirements of wearable devices. W doping can significantly increase the carrier concentration, Seebeck coefficient, and electrical conductivity of BST thin films. At 300 K, the power factor of the W-BST film is 2.25 times higher than that of the undoped film, reaching 13.75 μW cm-1 K-2. First-principles calculations showed that W doping introduces significant impurity peaks in the bandgap, in which W d electrons remarkably hybridize with the Sb and Te p electrons, leading to an improved electrical conductivity of BST films. Furthermore, W doping significantly reduces the work function of BST films, thereby improving the carrier mobility. A TEG module fabricated from four layers of W-BST thin films achieved a maximum output power density of 6.91 mW cm-2 at a temperature difference of 60 K. Application tests showed that the flexible TEG module could power a portable clock using the temperature difference between body temperature and room temperature. At a medium temperature of 439 K, the assembled TEG module can provide a stable output voltage of 1.51 V to power a LED. This study demonstrates the feasibility of combining inorganic thermoelectric materials with flexible substrates to create high-performance flexible TEGs.

Enhancing the piezoelectric coefficient of SrTiO3 nanocubes and PVDF film deposited by supersonic spraying for energy-harvesting nanogenerators

Many perovskites and their piezoelectric composites have been investigated for harvesting ambient mechanical energy over the past two decades; however, the prospects for their commercialization appear remote because of several practical challenges. Therefore, highly scalable supersonic cold-spraying technology was used to fabricate flexible piezoelectric films of poly(vinylidene fluoride) (PVDF) and a novel perovskite SrTiO3 (ST). Substantial shear stress was exerted on PVDF during cold spraying owing to the hydrothermally synthesized SrTiO3 nanocubes and supersonic velocity, and the resulting film delivered an effective piezoelectric coefficient (69.6 pm·V−1) as confirmed by piezo-response force microscopy. As a result, the piezoelectric nanogenerator yields a maximum power of 130 µW at a load resistance of 0.9 MΩ. The composite film exhibited durability for 21,000 tapping cycles with 20 N applied force and 7 Hz frequency. The flexibility endurance was confirmed from 3000 bending cycles. PENG attached to knee delivered 1 and 2.3 V on bending to 45 and 90°, respectively. After electrical poling, the PENG was subjected to a 20 N tapping force that yielded a piezopotential of 31 V. To the best of our knowledge, this is the first time piezoelectricity was obtained using an ST/PVDF composite via mechanical energy harvesting. The flexible PENG film deposited by cold-spraying shows good potential for wearable self-powered devices.

Giant Seebeck coefficient in SnTe thin films grown by thermal evaporation using layered structure engineering

In this work, we have reported a giant Seebeck coefficient (8033 µV/K) in SnTe thin films by controlling the layered structure using post growth annealing technique. The samples used in the current study were synthesized using a vacuum tube furnace having an evaporation temperature 700 °C, base pressure 180 m Torr and source to substrate distance 7 cm. Sn and Te metal powders with an equal weight ratio were evaporated on the glass substrate to form SnTe composite. Post-growth annealing in vacuum environment was performed for different time’s duration of 1–4 h with a step of one hour. XRD analysis reveals six diffraction peaks for all samples, which correspond to different crystal planes of SnTe structure. Raman spectra exhibit the presence of specific vibrational modes associated with SnTe. Using the giant value of Seebeck coefficient and moderate electrical conductivity, a strong power factor value of 8.1 × 10−3 W m−1 K−2 was observed for optimized sample (annealed for 3 h). The strongest values of Seebeck coefficient and power factor are supposed to be the layered structure of SnTe thin films which was verified by the SEM images.

Influence of Interfacial Tribo-Chemical and Mechanical Effect on Tribological Behaviors of TiN Film in Different Environments

A series of experiments has been conducted to investigate the tribological properties of a TiN film sliding against GCr15 steel balls in ambient air, low vacuum and high vacuum environments. Various friction loads and sliding velocities were also applied. The TiN film displays a steady-state friction stage after the running-in stage in all the above environments, while the durations of running-in stages are different. The steady-state friction coefficients of the TiN film were around 0.56 in ambient air and 0.3 in the high vacuum environment (1 × 10−5 mbar). In the low vacuum (1 × 10−2 mbar) environment, a low friction coefficient (around 0.19) was attained for all the friction tests on TiN film, irrespective of the applied load and sliding velocity. In the meantime, it was noticed that the applied loads and the sliding velocities would change the duration of the running-in stage before reaching the low friction coefficient. It is revealed by the analysis of wear tracks that the metal oxides induced by the tribo-chemical effect at the friction interface play an important role in affecting the tribological behaviors of the TiN films in different environments. The Raman results show that the main component of the metal oxides is hematite (α-Fe2O3), and the amount of iron oxide is related to the friction environment. The composition and quantity of iron oxides produced by the interfacial tribo-chemical effect affect the tribological behavior. The results also show that the mechanical wear process at the friction interface displays a polishing effect, which would reduce the surface roughness. The mechanical wear performance varies under different loads and velocities. The tribological tests results indicate that the interfacial tribo-chemical effect and mechanical wear process should be considered together rather than individually to interpret the tribological behaviors of TiN films in different environments.

Study on the anisotropic flow characteristics of wet particles in liquid-solid fluidized beds

In liquid-solid fluidized beds, the presence of a liquid film around the surface of particles influences their collision behavior, leading in turn to the restitution coefficient no longer a constant. The present study introduces a dynamic restitution coefficient for wet particles to describe its dynamic variation during the process of particles colliding. The liquid-solid two-phase flow is simulated with Eulerian-Eulerian two-fluid method incorporating the anisotropic kinetic theory of granular flow based on second-order moment (SOM) model, in view of the anisotropy of particle fluctuations. This study aims to probe into the influence of liquid film and anisotropy of particle fluctuation on the particle-particle interactions and collision mechanisms. The predicted particle velocity and solid volume fraction are verified by the Limtrakul's et al. experiments. The simulated results show that the particle velocity fluctuations exhibit significant anisotropy, and the SOM model is superior to the KTGF model in capturing inhomogeneity and anisotropy of the flow field. The existence of a liquid film enhances energy dissipation during particle collisions and diminishes the anisotropy of particle velocity fluctuations. Also, the enhancement of particle density leads to a thicker liquid film and higher restitution coefficient, while the second-order moments are weakened and the anisotropy is remarkable. Furthermore, the effect of liquid viscosity on the liquid film thickness and restitution coefficient is more significant, where the particle fluctuations are reduced and the anisotropy is intensified by enhancing the liquid viscosity. In brief, both the liquid film and the anisotropy have impact on liquid-solid two-phase flow, by comparison, the effect of anisotropy is greater than liquid film.

All‐organic shell–core PVDF/PMMA composite fiber films with enhanced piezoelectric performance for flexible sensing and energy harvesting

AbstractThe demand for self‐powered sensing technology and energy harvesting system necessitates high‐performance and flexible piezoelectric materials. This paper presents a novel approach utilizing coaxial electrospinning to fabricate all‐organic PVDF/PMMA piezoelectric fiber films with a shell–core structure. The resulting fiber films, cut into 2 × 2 cm2 square pieces and hot‐pressed every three pieces, demonstrate enhanced piezoelectric properties while retaining high flexibility. The interaction between the CO bonds in the PMMA polymer and the CH2 in PVDF promotes the arrangement of F atoms in PVDF, enhancing the content of the piezoelectric active phase. Additionally, the coaxial electrospinning process fosters vertically oriented hydrogen bonds between PVDF and PMMA, augmenting cross‐linking and improving mechanical properties. Notably, when the PVDF to PMMA layer volume ratio is 5:1, the piezoelectric coefficient (|d33|) of the composite fiber film exhibits a significant 60% increase from 10 pC N−1 in neat PVDF to 16 pC N−1. This research holds substantial promise for applications in self‐powered sensing and energy harvesting piezoelectric materials.

Promoting the optoelectronic and nonlinear optics properties of MoS2 nanosheets via metal Al anchoring

Molybdenum disulfide (MoS2) has attracted much attention in the field of optoelectronic materials due to its stability and adjustable bandgap structure. However, improving the optoelectronic properties of MoS2 is still a challenging research. Herein, Al doped MoS2 (AMS) films were prepared by a simple single-step magnetron sputtering method. The bonding modes of Al implantation and auxiliary MoS2 were investigated by adjusting metal Al anchoring. The successful synthesis of AMS films was confirmed by the analysis of X-ray diffraction and X-ray photoelectron spectroscopy measurements to investigate the diffraction peaks of Al and Al2S3 and the valence electron structures of Al3+. Compared to MoS2, the A1g Raman peaks of AMS films are slightly blue-shifted, and the peak positions of both Mo3d and S2p are slightly shifted towards higher binding energies. This is attributed to the surface plasmon resonance effect produced by Al doping resulting in a large amount of electron transfer to the conduction band (CB) of MoS2. In addition, the density functional theory calculations reveal that Al doping of MoS2 results in a higher concentration of electrons in CB of MoS2, the band gap of MoS2 can be adjusted by changing the doping concentration of Al. The Z-scan results illustrated that MoS2 was converted from saturable absorption to reverse saturable absorption (RSA) by adjusting the sputtering power of Al. This is attributed to the fact that Al doping increases the electron concentration in the CB of MoS2, which promotes the RSA of the excited states and doping energy levels of AMS films. The values of the nonlinear absorption coefficients of AMS films are 2–5 times higher than those of MoS2, which significantly improves the nonlinear absorption performance of MoS2. The carrier relaxation process and kinetic mechanism of AMS films were investigated by transient absorption spectroscopy, moderate doping of Al can effectively improve the carrier lifetime. This implies that AMS films have good optoelectronic properties and have a wide application potential in optoelectronic devices.