Strain Engineering Research Articles

Strain engineering the spin-valley coupling of the R-stacking sliding ferroelectric bilayer 2H-VX2 (X = S, Se, Te)

The emergence of magnetic transition metal dichalcogenides has significantly advanced the development of valleytronics due to the spontaneous breaking of time-reversal symmetry and space-inversion symmetry. However, the lack of regulation methods has prevented researchers from exploring their potential applications. Herein, we propose to use strain engineering to control the spin-valley coupling in the sliding ferroelectric bilayer 2H-VX2 (X = S, Se, Te). Four multiferroic states are constructed by combining the sliding ferroelectricity and antiferromagnetism in the R-stacking bilayer VX2, where the spin and valley polarizations are coupled together from the layer-dependent spin-polarized band structures. By applying a small external strain or pressure on the out-of-plane van der Waals direction, we predicted that there is an antiferromagnetic to magnetic transition in the bilayer VX2, leading to the interesting spin-polarized and chiral circularly polarized radiation at K+ and K- valleys, similar to those found in the magnetic monolayer. To comprehend the coupling between various degrees of freedom in these multiferroic systems, we have developed an effective k·p model. This model unveils a linear relationship between the electric polarization generated by interlayer sliding and the energy difference of the valence band maximum at K+ and K- valleys. Thus, providing an alternate method to measure the electric polarization in the sliding ferroelectrics. Based on the strong coupling between the strain, spin-valley, and electric polarization, it is likely to use the strain to control the interesting emerging properties of 2H-VX2 such as the anomalous valley Hall effect.

Theoretical study on photoelectric properties of ferroelectric photovoltaic perovskite CsGeBr3 based on first-principle calculations

Abstract Ferroelectric photovoltaic materials with intrinsic spontaneous polarization have attracted great attention because the ferroelectric polarization can promote the directional migration of electrons and holes, and reduce the trend of carrier recombination. Recently, the evidence of ferroelectricity in the typical three-dimensional all-inorganic halide perovskites CsGeX3, with band gaps of 1.6 eV to 2.3 eV has been confirmed. But the spontaneous polarization of ferroelectric perovskite CsGeX3 is ~10 to 20 μc/cm2 which is weaker than that of ABO3 (~26 to 75 μc/cm2). Strain engineering has a significant influence on the ferroelectric polarization of semiconductor materials by controlling the lattice scaling and the internal atomic spacing. Hence, in this work, strain engineering is introduced to enhance the ferroelectric polarization and maintain the photovoltaic properties of ferroelectric perovskite CsGeBr3. In this paper, we studied the ferroelectric polarization and photoelectric properties of ferroelectric perovskite CsGeBr3 under different triaxial compressive strain based on first-principle calculations. The calculated results show that when the applied compressive strain increases from 0% to -4%, the spontaneous polarization of ferroelectric perovskite CsGeBr3 increases from 14.23 μc/cm2 to 51.61 μc/cm2, and the band gap reduces from 2.3631 eV to 1.5310 eV. The effective mass of electrons and holes gradually reduces, exciton binding energies decrease from 48 meV to 5 meV, and the optical absorption coefficient is strongly enhanced from 3×105 cm-1 to 5×105 cm-1 in visible range. Besides, the power conversion efficiency(PCE) of CsGeBr3 is significantly increased from 16.95% to 26.77%. Therefore, the results indicate that the application of compressive strain can increase the ferroelectric polarization and even improve the original photovoltaic performance of ferroelectric perovskite CsGeBr3. Our theoretical calculations can provide useful insights and beneficial guidance into experimental studies of ferroelectric perovskites in photoelectric applications.

Strain-modulated electronics enabled by surface piezoelectricity

The strain-induced polarization in a piezoelectric semiconductor is an effective strategy to modulate its current transport. However, the piezoelectricity is degraded by the free charges, and the inevitable compromise of piezoelectricity and semiconductivity severely limits the material choice and device performance. We tackle this dilemma by investigating the polarization caused by broken translational symmetry of a material surface. The ubiquitous surface piezoelectricity of solid materials enables the strain-induced polarization change to control the electrical transport effectively in crystals without bulk piezoelectricity. The Schottky barrier is shown to prohibit the bulk charges from screening the surface polarization. The strain engineering of the barrier height leads to an exponential modulation of the current, and an unprecedented gauge factor of 3.10×108 and an on/off ratio of 2.53×105 are demonstrated. The outstanding tunability of current with the synergistic effect of the surface piezoelectricity and metal-semiconductor contact unlocks the device development from various materials.

Theoretical insights into the structural, electronic and gas-sensing properties of Sc-decorated black phosphorus via strain engineering

Structural and electronic properties of Sc-decorated black phosphorus (SP) and its gas sensing for NO molecule were investigated using density functional theory with the emphasis on the response to applied strain. It found that SP transformed into indirect bandgap semiconductor, and converted into a metal characteristic under strain. SP showed strong interaction with the NO with a high adsorption energy of −2.92 eV since the orbital hybridization and extensive charge transfer, and exhibited 3.3-fold sensitivity compared to black phosphorus, suggesting that SP was a potential NO sensor. Furthermore, strain engineering provided an effective route to facilitate the desorption of NO.

Can large lattice volume always facilitate ion diffusion in solids?

Large lattice volume is usually expected to expand the bottleneck size and enlarge free volume for fast Li ion transport in solids. But the universality of lattice expansion decreasing activation energy barrier for Li ion migration is still debatable. Herein, our molecular dynamics simulations and density functional theory calculations detect the unconventional phenomenon of lattice expansion increasing activation energy barrier for Li ion migration in β-Li3PS4, Li4SnS4 and Li4GeS4 sulfides with the hcp-type anion sublattice, and discover the underlying mechanism. On one hand, lattice expansion enlarges the relative energies between the octahedral and tetrahedral Li sites, and correspondingly increase activation energy barrier for tetrahedral Li ions migration along the Tet-Oct-Tet migration paths in β-Li3PS4, Li4SnS4 and Li4GeS4. On the other hand, the lattice dynamics calculations show Li energy landscapes of β-Li3PS4, Li4SnS4 and Li4GeS4 are anharmonic and enlarging lattice volume make the local minimum of Li potential energy surface flatter, simultaneously reduce the relative energy of Li occupation site, eventually resulting in the higher activation energy barrier for Li ion migration. Thus, understanding the effect of lattice volume on ion migration in solids should not only consider the factor of bottleneck size and free volume, but also combine the aspects of Li ion occupation type, Li ion migration path and anion sublattice type. These new understandings of the lattice expansion increasing activation energy barrier for ion migration would further promote the further optimization and rational design of superionic conductors by element doping or strain engineering.

Feeling the strain: Enhancing the thermodynamics characteristics of magnesium nickel hydride Mg2NiH4 for hydrogen storage applications through strain engineering

This work is based on density functional theory (DFT) and studies the structural, electronic, thermodynamic properties and dehydrogenation kinetics of the hydride Mg2NiH4 under different uniaxial and biaxial strain applied to Mg2Ni or Mg2NiH4. structural properties are first studied based on generalized gradient (GGA) and local density (LDA). Thermodynamic and electronic properties and dehydrogenation kinetics are then studied using the GGA method based on the Perdew-Burke-Ernzerhor (PPE) approximation. The results obtained show that uniaxial/biaxial tensile and compressive strains are capable of inducing structural deformation by increasing the value of the strain step on both Mg2Ni and Mg2NiH4, and that these strains applied to Mg2NiH4 are capable of reducing the stability of the system more than strains applied to Mg2Ni, due to the contribution of strain energy. More specifically, it lowers the enthalpy of formation to −40 kJ/mol.H2 under compressive strain ε = −7.5% or biaxial tensile strain ε = +7.8%, which corresponds exactly to the ideal value suggested by the US Department of Energy (DOE) for materials suitable for hydrogen storage. And the decomposition temperature fell within the fuel cell operating range (PEM) of 289–393 K. On the other hand, under uniaxial and biaxial strains, the activation energy of hydrogen atom diffusion in Mg2NiH4 varied between 0.40 eV and 0.22 eV, resulting in a remarkable improvement in dehydrogenation properties. Analysis of the total (TDOS) and partial (PDOS) density curves shows that the Mg2NiH4 system has a metallic characteristic, and that this characteristic is maintained by increasing the strain pitch, with a variation in the energy width of the valence band.

Meta-GGA study of 2D AlN/BN planer heterostructure and performance enhancement via strain engineering.

The 2D AlN/BN planer heterostructure is a promising wide band gap semiconductor, but systematic studies of its bandgap and optical characteristics under applied strain are scarce. Here, the engineering property of 2D AlN/BN comprising bandgap nature transition and optical absorption capability (from unstrained to strained) have been investigated using density functional theory calculations. The formation energy calculations confirm the stability of the simulated nanoheterostructure. The electronic band structure calculations demonstrate that nanoheterostructure is an indirect bandgap material with a large bandgap of 5.26 eV, which can be modified effectively by applying strain. According to the calculations, the transition from indirect to direct band gap behavior has been observed at +15% biaxial strain with 2.71 eV band gap energy. Meanwhile, calculations for optical absorption and dielectric function reveal that the system has significant absorption peaks in the ultraviolet region which are very sensitive to applied strain. As strain increases, the first absorption peaks are shifted towards a lower energy range from 5.73 eV (Ꜫ= 0 %) to 3.76 eV (Ꜫ = +15%), which features an enhancement of optical absorption for solar and solar-blind regions. Furthermore, we determined that the band edge positions in 2D AlN/BN straddled the water redox potential under strain, indicating its effectiveness as a proficient photocatalyst. These characteristics make 2D AlN/BN planer nanoheterostructure a promising candidate for applications in optoelectronics and photocatalytic water splitting performance. First principles computations based on density functional theory were employed to carry out all the calculations with a self-consistent approach. For solving the Kohn-Sham equations, the first principles dependent full-potential linearized augmented plane wave scheme were adopted. For addressing the exchange-correlation effects, the generalized gradient approximation of PBEsol functional was used. To prevent interaction between the periodic images, we have inserted a vacuum region of 10 Å in the z-direction. Non-negligible weak dispersion corrections in nanoheterostructure were considered by using the DFT-D3 method of Grimme's. The locally modified Becke-Johnson (lmBJ) exchange potential has also been applied to compute electronic and optical properties in this research to obtain more accurate information.

Tuning Electrocatalytic Activities of Dealloyed Nanoporous Catalysts by Macroscopic Strain Engineering.

It is technically challenging to quantitatively apply strains to tune catalysis because most heterogeneous catalysts are nanoparticles, and lattice strains can only be applied indirectly via core-shell structures or crystal defects. Herein, we report quantitative relations between macroscopic strains and hydrogen evolution reaction (HER) activities of dealloyed nanoporous gold (NPG) by directly applying macroscopic strains upon bulk NPG. It was found that macroscopic compressive strains lead to a decrease, while macroscopic tensile strains improve the HER activity of NPG, which is in line with the d-band center model. The overpotential and onset potential of HER display approximately a linear relation with applied macroscopic strains, revealing an ∼2.9 meV decrease of the binding energy per 0.1% lattice strains from compressive to tensile. The methodology with the high strain sensitivity of electrocatalysis, developed in this study, paves a new way to investigate the insights of strain-dependent electrocatalysis with high precision.

Strain and defect engineering of high-performance monolayer two-dimensional material/Ag nanoparticles optoelectronic FET sensor through multiple laser shock

The development of sensor devices that detect low-concentrations hydrogen at room temperature is becoming increasingly important for the safe use of hydrogen. In this study, the introduction of strain and defects in two-dimensional materials has been realised by laser shock and its application in gas sensing. The strain and defect density of monolayer MoS2 increase after multiple laser shock, providing more active sites for gas adsorption and improving the ability to adsorb hydrogen atoms. Under the synergistic effect of strain and defects, the response of non-noble metal nanoparticles/MoS2 photoelectric hydrogen sensors is accelerated, and their sensing performance (83% for 200 ppm) is 9.5 times higher than that of pure MoS2 devices (8.7% for 200 ppm) at room temperature (25 ℃). As a proof of concept, laser shock induced 2D material strain and defect engineering has opened up new ideas for improving the performance of photoelectric gas sensors at room temperature.

Dynamic and controlled stretching of macroscopic crystalline membranes towards unprecedented levels

Imposing and controlling strain in materials such as semiconductors or ferroelectrics is a promising way to obtain new or enhance existing properties. Although the field of strain engineering has seen a rapid expansion over the last two decades, straining semiconductor membranes over large areas remains a challenge. A generic way of tuning strain and hence band structure and electric or magnetic properties of any crystalline material can be obtained by compression of a composite structure involving poorly compressible elastomers. Mechanically similar to the principle of a hydraulic press, this work proposes a device and describes analytically a methodology to easily strain macroscopic membranes up to unprecedented values. Using in-situ X-ray diffraction and Raman spectroscopy, we tuned the biaxial strain in silicon membranes up to a value of 2.1 %, paving the way for new studies in the field of strain related physics, from semiconductors to perovskite oxide multiferroics.

High Strain Engineering of a Suspended WSSe Monolayer Membrane by Indentation and Measured by Tip‐Enhanced Photoluminescence

AbstractStraintronics involves the manipulation and regulation of the electronic characteristics of 2D materials through the use of macro‐ and nano‐scale strain engineering. In this study, an atomic force microscope (AFM) coupled with an optical system is used to perform indentation measurements and tip‐enhanced photoluminescence (TEPL), allowing to extract the local optical response of a suspended monolayer membrane of ternary WSSe at various levels of deformation, up to strains of 10%. The photoluminescence signal is modeled considering the deformation, stress distribution, and strain dependence of the WSSe band structure. An additional TEPL signal is observed that exhibits significant variation under strain, with 64 meV per percent of elongation. This peak is linked to the highly strained 2D material lying right underneath the tip. The amplification of the signal and its relation to the excitonic funneling effect are discussed in a more comprehensive model. The diffusion caused by Auger recombination against the radiative excitonic decay will also be compared. TEPL is used to examine and comprehend the local physics of 2D semi‐conducting materials subjected to extreme mechanical strain. Chemical vapor deposition‐fabricated 2D ternaries possess high strain resistance, comparable to the benchmark MoS2, and a high Young's modulus of 273 GPa.

Valley-Polarized Quantum Hall Phase in a Strain-Controlled Dirac System.

In multivalley systems, the valley pseudospin offers rich physics going from encoding of information by its polarization (valleytronics), to exploring novel phases of matter when its degeneracy is changed. Here, by strain engineering, we reveal fully valley-polarized quantum Hall phases in the Pb_{1-x}Sn_{x}Se Dirac system. Remarkably, when the valley energy splitting exceeds the fundamental band gap, we observe a "bipolar quantum Hall phase," heralded by the coexistence of hole and electron chiral edge states at distinct valleys in the same quantum well. This suggests that spatially overlaid counterpropagating chiral edge states emerging at different valleys do not interfere with each other.

Strain Engineering of Twisted Bilayer Graphene: The Rise of Strain-Twistronics.

The layer-by-layer stacked van der Waals structures (termed vdW hetero/homostructures) offer a new paradigm for materials design-their physical properties can be tuned by the vertical stacking sequence as well as by adding a mechanical twist, stretch, and hydrostatic pressure to the atomic structure. In particular, simple twisting and stacking of two layers of graphene can form a uniform and ordered Moiré superlattice, which can effectively modulate the electrons of graphene layers and lead to the discovery of unconventional superconductivity and strong correlations. However, the twist angle of twisted bilayer graphene (tBLG) is almost unchangeable once the interlayer stacking is determined, while applying mechanical elastic strain provides an alternative way to deeply regulate the electronic structure by controlling the lattice spacing and symmetry. In this review, diverse experimental advances are introduced in straining tBLG by in-plane and out-of-plane modes, followed by the characterizations and calculations toward quantitatively tuning the strain-engineered electronic structures. It is further discussed that the structural relaxation in strained Moiré superlattice and its influence on electronic structures. Finally, the conclusion entails prospects for opportunities of strained twisted 2D materials, discussions on existing challenges, and an outlook on the intriguing emerging field, namely "strain-twistronics".

Strategies for the efficient biosynthesis of β-carotene through microbial fermentation.

β-Carotene is an orange fat-soluble compound, which has been widely used in fields such as food, medicine and cosmetics owing to its anticancer, antioxidant and cardiovascular disease prevention properties. Currently, natural β-carotene is mainly extracted from plants and algae, which cannot meet the growing market demand, while chemical synthesis of β-carotene cannot satisfy the pursuit for natural products of consumers. The β-carotene production through microbial fermentation has become a promising alternative owing to its high efficiency and environmental friendliness. With the rapid development of synthetic biology and in-depth study on the synthesis pathway of β-carotene, microbial fermentation has shown promising applications in the β-carotene synthesis. Accordingly, this review aims to summarize the research progress and strategies of natural carotenoid producing strain and metabolic engineering strategies in the heterologous synthesis of β-carotene by engineered microorganisms. Moreover, it also summarizes the adoption of inexpensive carbon sources to synthesize β-carotene as well as proposes new strategies that can further improve the β-carotene production.

Separated Electronic and Strain Interfaces in Core/Dual‐Shell Nanowires: Unlocking the Potential of Strained GaAs for Applications Across Near‐Infrared

AbstractSemiconductor nanowires have inspired plenty of novel nanotechnology device concepts in photonics, electronics, and sensing, owing to their unique functionalities and integrability in heterogeneous platforms. Lattice‐mismatched core/shell heterostructures, in particular, open new avenues for strain engineering and material properties modification. A notable case is the widely tunable tensile strain in the core of GaAs/InxAl1‐xAs core/shell nanowires, which can be used to tailor the GaAs bandgap for applications across near‐infrared, like optical fiber telecommunication, imaging, photovoltaics, etc. As it is shown here, though, the bandgap narrowing under high tensile strain in the GaAs core is accompanied by fast non‐radiative recombination, which is undesirable for any device application. The limiting role of the lattice‐mismatched core/shell interface is revealed, and a novel core/dual‐shell heterostructure that employs an intermediate AlyGa1‐yAs shell (spacer) is proposed. This spacer decouples the GaAs/AlyGa1‐yAs interface, which confines electrons and holes into GaAs, from the lattice‐mismatched AlyGa1‐yAs/InxAl1‐xAs one, whereas the strain in GaAs is unaffected. Choosing the optimal spacer thickness, the photoluminescence yield increases significantly, with longer emission decay lifetimes and slower carrier cooling rates. Besides unlocking the potential of GaAs for photonic applications across near‐infrared, the proposed heterostructure concept can also be adopted for other material systems.

Ab-initio study of strain-tunable g-GaN/BN nanoheterostructure for optoelectronic and photocatalytic applications.

Two-dimensional (2D) nanoheterostructures of materials, integrating various phase or materials into a single nanosheet have stimulated large-scale research interest for designing novel two dimensional devices. In contemporary analysis present work, we examined the structural and electronic properties of the isolated 2D BN and GaN monolayers. We have investigated the structural stability and optoelectronic and photocatalytic response of the g-GaN/BN nanoheterostructure along with its response to strain. Nanoheterostructure g-GaN/BN is predicted to be a direct bandgap semiconductor with wide gap of 4.45eV, whose value can be effectively modulated by applied strain ( , ranging from 4.55 ( = - 4%) to 3.58eV ( = 8%). We also discovered that the tensile strain of 8% can substantially tune the direct bandgap of nanoheterostructure to indirect band gap nature. Even more important, the biaxial tensile strain engineering accentuates an enhancement of optical absorption in the UV region, broadening the light harvesting of the g-GaN/BN nanoheterostructure with the shifting of first absorption peak from 4.64 ( = - 4%) to 3.71eV ( = 8%). Furthermore, strain-tuned band edge potentials arrangement perfectly fits the water reduction and oxidation redox potentials. Our findings portend that the g-GaN/BN nanoheterostructure has application in prospective nanoscale optoelectronic devices and photocatalytic hydrogen evolution system. First principles calculations in this study are performed using density functional theory. Generalized gradient approximation within PBEsol functional employed to address the electron-electron exchange-correlation effects. For avoiding periodic interactions between the layers, we have inserted a vacuum region of thickness 10Å in the z-direction. For ensuring the convergence accuracy of the computed results, convergence criteria of the iteration process is set to be 0.0001eV. Local modified Becke-Johnson, a semi local functional, is applied for calculating electronic and optical properties for more accuracy of results. As in layered 2D nanoheterostructure, a factual depiction of the van der Waals interactions cannot be provided by conventional DFT techniques. Accordingly, in order to incorporate these interactions, we had employed the dispersion correction method of Grimme's.

Tensile Strain‐Mediated Bimetallene Nanozyme for Enhanced Photothermal Tumor Catalytic Therapy

Nanozymes have demonstrated significant potential in combating malignant tumor proliferation through catalytic therapy. However, the therapeutic effect is often limited by insufficient catalytic performance. In this study, we propose the utilization of strain engineering in metallenes to fully expose the active regions due to their ultrathin nature. Here, we present the first report on a novel tensile strain‐mediated local amorphous RhRu (la‐RhRu) bimetallene with exceptional intrinsic photothermal effect and photo‐enhanced multiple enzyme‐like activities. Through geometric phase analysis, electron diffraction profile, and X‐ray diffraction, it is revealed that crystalline–amorphous heterophase boundaries can generate approximately 2% tensile strain in the bimetallene. The ultrathin structure and in‐plane strain of the bimetallene induce an amplified strain effect. Both experimental and theoretical evidence support the notion that tensile strain promotes multiple enzyme‐like activities. Functioning as a tumor microenvironment (TME)‐responsive nanozyme, la‐RhRu exhibits remarkable therapeutic efficacy both in vitro and in vivo. This work highlights the tremendous potential of atomic‐scale tensile strain engineering strategy in enhancing tumor catalytic therapy.

Tensile Strain-Mediated Bimetallene Nanozyme for Enhanced Photothermal Tumor Catalytic Therapy.

Nanozymes have demonstrated significant potential in combating malignant tumor proliferation through catalytic therapy. However, the therapeutic effect is often limited by insufficient catalytic performance. In this study, we propose the utilization of strain engineering in metallenes to fully expose the active regions due to their ultrathin nature. Here, we present the first report on a novel tensile strain-mediated local amorphous RhRu (la-RhRu) bimetallene with exceptional intrinsic photothermal effect and photo-enhanced multiple enzyme-like activities. Through geometric phase analysis, electron diffraction profile, and X-ray diffraction, it is revealed that crystalline-amorphous heterophase boundaries can generate approximately 2% tensile strain in the bimetallene. The ultrathin structure and in-plane strain of the bimetallene induce an amplified strain effect. Both experimental and theoretical evidence support the notion that tensile strain promotes multiple enzyme-like activities. Functioning as a tumor microenvironment (TME)-responsive nanozyme, la-RhRu exhibits remarkable therapeutic efficacy both in vitro and in vivo. This work highlights the tremendous potential of atomic-scale tensile strain engineering strategy in enhancing tumor catalytic therapy.

Nanoimprint-induced strain engineering of two-dimensional materials

The high stretchability of two-dimensional (2D) materials has facilitated the possibility of using external strain to manipulate their properties. Hence, strain engineering has emerged as a promising technique for tailoring the performance of 2D materials by controlling the applied elastic strain field. Although various types of strain engineering methods have been proposed, deterministic and controllable generation of the strain in 2D materials remains a challenging task. Here, we report a nanoimprint-induced strain engineering (NISE) strategy for introducing controllable periodic strain profiles on 2D materials. A three-dimensional (3D) tunable strain is generated in a molybdenum disulfide (MoS2) sheet by pressing and conforming to the topography of an imprint mold. Different strain profiles generated in MoS2 are demonstrated and verified by Raman and photoluminescence (PL) spectroscopy. The strain modulation capability of NISE is investigated by changing the imprint pressure and the patterns of the imprint molds, which enables precise control of the strain magnitudes and distributions in MoS2. Furthermore, a finite element model is developed to simulate the NISE process and reveal the straining behavior of MoS2. This deterministic and effective strain engineering technique can be easily extended to other materials and is also compatible with common semiconductor fabrication processes; therefore, it provides prospects for advances in broad nanoelectronic and optoelectronic devices.

Early-onset of pressure-induced metallization in iron-doped multilayered molybdenum disulfide

Chemical doping-induced magnetism in semiconducting transition metal dichalcogenides (TMDC) can have significant implications in electrically controlled spintronics. In addition, strain engineering of the layered structures of TMDCs can further allow for tuning the interlayer van der Waals (vdW) bonds and controlling their electronic properties. Of particular interest are the effects of Fe doping coupled with strain tuning on the vdW bonds and associated electronic properties of Fe:MoS2. Here, we have investigated compressive strain tuning effects on the structural and vibrational properties of Fe:MoS2 using in situ angle-dispersive x-ray diffraction and Raman scattering spectroscopy at quasi-hydrostatic pressures up to 25.0(1) GPa. Our results indicate that Fe:MoS2 undergoes isostructural electronic transitions similar to those in pristine MoS2, but at significantly lower pressures. Sudden changes in the microscopic strain, Raman peak splitting, and phonon softening are observed at the transition pressures, suggesting that the structural instability introduced by the Fe dopants is responsible for the early onset of the transitions. The significant effects of Fe dopants on the interlayer vdW bonding, as well as the structural and phononic properties under compressive strain indicate a strategy for modulating the electronic and ferromagnetic properties of TMDCs.