Mo Doping Research Articles

A Bandgap‐Tuned Tetragonal Perovskite as Zero‐Strain Anode for Potassium‐Ion Batteries

AbstractPIBs are emerging as a promising energy storage system due to high abundance of potassium resources and theoretical energy density, however, progress of PIBs is severely hindered by structural instability and poor cycling of anode material during continual insertion and extraction of larger‐sized K+. Hence, developing anode material with structural stability and stable cycling remains a great challenge. Herein, band gap‐tuned Mo‐doped and carbon‐coated lead titanate (CMPTO) with zero‐strain K+ storage is presented as ultra‐stable PIBs anode. Mo doping introduces narrowed band gap and optimized crystal lattice for enhanced intrinsic electron and ion transfer. Demonstrated by in situ XRD characterizations, the crystal structure stays stable with unchanged peak positions, fully revealing zero‐strain characteristic of CMPTO anode during potassium storage for stable cyclic capability. Ultimately, CMPTO anode achieved ultra‐stable cycling performance of 7000 cycles at 500 mA g−1 with high capacity retention of 90 % and considerable specific capacity of 130.9 mAh g−1 after 600 cycles at 100 mA g−1; with relatively large density, CMPTO realized eminent volumetric capacity of 1111.09 mAh cm−3 and ultra‐long cycling life of 10000 cycles at 7041 mA cm−3. This work introduces a promisingly new route into developing anode materials with ultra‐stable performance for PIBs.

Molybdenum-Modified Niobium Oxide: A Pathway to Superior Electrochromic Materials for Smart Windows and Displays

Electrochromic materials enable the precise control of their optical properties, making them essential for energy-saving applications such as smart windows. This study focuses on the synthesis of molybdenum-doped niobium oxide (Mo-Nb2O5) thin films using a one-step hydrothermal method to investigate the effect of Mo doping on the material’s electrochromic performance. Mo incorporation led to distinct morphological changes and a transition from a compact granular structure to an anisotropic rod-like feature. Notably, the MN-3 (0.3% Mo) sample displayed an optimal electrochromic performance, achieving 77% optical modulation at 600 nm, a near-perfect reversibility of 99%, and a high coloration efficiency of 89 cm2/C. Additionally, MN-3 exhibited excellent cycling stability, with only 0.8% degradation over 5000 s. The MN-3 device also displayed impressive control over color switching, underscoring its potential for practical applications. These results highlight the significant impact of Mo doping on improving the structural and electrochromic properties of Nb2O5 thin films, offering improved ion intercalation and charge transport. This study underscores the potential of Mo-Nb2O5 for practical applications in energy-efficient technologies.

Regulating the electronic structure of nickel phosphides via interface engineering and molybdenum doping boosts benzyl alcohol oxidation coupled with hydrogen production

Coupling the electrocatalytic benzyl alcohol oxidation reaction (BAOR) with hydrogen evolution reaction (HER) presents a favorable energy conversion method. However, the development of highly efficient bifunctional electrocatalysts poses significant challenges. In this study, a Mo doped biphasic Ni2P-Ni12P5 heterostructure (Mo-Ni2P/Ni12P5@NF) has been developed to serve as the efficient bifunctional electrocatalyst. The Mo-Ni2P/Ni12P5@NF resulted in exceptional activities for both the BAOR and HER. The electrolyzer cell using Mo-Ni2P/Ni12P5@NF as anode and cathode operates at an impressively low cell voltage of merely 1.38 V to achieve the current density of 10 mA cm−2 in a benzyl alcohol-containing aqueous solution. Experimental results and density functional theory (DFT) calculations indicate that the introduction of Mo can significantly modulate the electronic structure of Ni-based phosphide catalysts and adjust for the d-band center of the active Ni sites. This modulation significantly optimizes the adsorption capabilities for both benzyl alkoxide (Ph-CH2O-) and the H* intermediates on Mo-Ni2P/Ni12P5@NF, thereby increasing electrocatalytic activity toward BAOR and HER respectively. Our work offers a valuable insight into designing bifunctional electrocatalysts and highlights the potential of Mo doping systems to produce hydrogen and value-added products efficiently.

First-principles study on impact of Mo doping on the formation enthalpy and electronic structure of Li2MgN2H2 material

The influence of Mo doping on the formation enthalpy and electronic structure of Li2MgN2H2 material, as well as the specific improvement mechanism of its hydrogen storage properties, were investigated by employing the first-principles calculation method. The calculation results exhibit that when Mo is doped into the Li2MgN2H2 material, it is more inclined to take up Mg lattice site at the 8c position. For the Li2MgN2H2 material, Mo doping can effectively reduce its formation enthalpy by ca. 91.16 kJ/mol, thus resulting in the reduction of its structural stability. Moreover, when the Li2MgN2H2 material is doped with Mo, its cell volume increases, and its band gap narrows obviously. Meanwhile, the strong force between Mo and N causes the bond strengths of N–H and Li–N to weaken significantly. The aforementioned factors are beneficial to the improvement of its hydrogen sorption kinetics. This work aims to provide theoretical guidance for further development of new efficient catalysts to promote the Li–Mg–N–H material's application.

Electronic structure engineering of NiFe hydroxide nanosheets via ion doping for efficient OER electrocatalysis

Nickel-iron layered double hydroxides (NiFe-LDH) with tunable catalytic properties have shown promise as an outstanding alternative to ruthenium iridium oxide for the oxygen evolution reaction (OER). However, the intrinsic activity of such electrocatalysts is suboptimal, and a considerable gap remains in understanding the working mechanism. To address this issue, we employ a convenient corrosion method to synthesize Mo-modified nickel–iron hydroxide (Mo-NiFeOxHy) ultrathin nanosheets. Mo-NiFeOxHy demonstrates excellent OER activity, requiring only 216 mV at a current density of 10 mA cm−2, with enhanced stability. Theoretical calculations reveal that the Mo doping induces material distortion, shifting the d-band center closer to the Fermi level, which accelerates the kinetic rate and catalytic activity. In situ Raman experiments show that doping with Mo promotes the rapid formation of high-oxidation-state transition metal hydroxide species, further enhancing the catalytic properties of Mo-NiFeOxHy in OER. This work provides a novel strategy to tailor the structure and composition of NiFe-based electrocatalysts, demonstrating a great potential to break barriers in OER.

Study on thermoelectric properties and atomic-scale mechanism of B-site molybdenum-modified La0.1Sr0.9TiO3

Extensive studies on strontium titanate thermoelectric materials have shown that their poor conductivity results in a low ZT value. However, elemental doping can effectively improve the thermoelectric properties of these materials. In this study, a two-step sintering process was applied, using physical mixing to introduce 1 % molybdenum powder as a modification to the lanthanum-doped strontium titanate solid powder (La0.1Sr0.9TiO3). The obtained sample exhibited a maximum conductivity of 7830 S/m, with a maximum ZT of 0.12. Furthermore, this study combined experimental data with first-principles simulation calculations to elucidate the mechanism at the atomic scale. The incorporation of Mo6+ in place of Ti4+ at the B-site by molybdenum (Mo) adds two free electrons, leading to an elevated carrier concentration. This change concurrently reduces the Fermi level of the material and improves mobility, collectively resulting in a substantial increase in electrical conductivity. Phonon simulation indicated that Mo doping increased structural defects, thereby reducing lattice thermal conductivity. This significant enhancement in electrical conductivity and decrease in lattice thermal conductivity collectively increased the ZT value of the material.

Influence of Mo dopants on the vibrational, emission, dielectric, electrical, and magnetic properties of combustion synthesized ZnFe2O4 nanostructures for optoelectronic and spintronic applications

This report investigates the dielectric and magnetic behavior of Molybdenum (Mo)-incorporated ZnFe2O4 prepared via combustion route with different dopant concentrations (0.0, 0.1, 0.25, 0.5, 0.75, and 1.0 wt.%). XRD patterns reveal the cubic spinel structures with a slight increase in lattice constant while replacing Mo at Fe sites. Mo doped induced lattice constant increase from 8.444 to 8.469 Å coupled with a significant increase in density. Raman spectroscopy reveals a decrement in the peak broadening of the A1g mode at higher Mo concentrations, indicating longer phonon lifetimes. Scanning electron microscopy (SEM) and EDX analysis confirm the agglomerated pseudo-spherical structures with uniform elemental distribution over the surface. Further, the dielectric constant values exhibit a slightly decreasing trend with increasing frequency, and the mechanisms were discussed based on the intrinsic polarization due to the charge imbalance between Fe3+ and Fe2+ states. Further, the magnetic measurements confirm the soft magnetic behavior with saturation magnetization ranging from 13.72 to 14.61 emu/g and coercivity between 07 (Oe) to 44 (Oe). The overall findings demonstrate that Mo doping in ZnFe₂O₄ significantly modifies the dielectric and magnetic properties, making it a promising material for various technological applications.

Molybdenum doping leads to faster photo-dissolution of commercial molybdate red pigment than chrome yellow pigment under sunlight irradiation

The photo-dissolution of lead chromate pigments poses specific environmental hazards. In this study, we report that doping molybdenum in lead chromate pigments, resulting in commonly known molybdate red pigment, increases the risk of heavy metal leaching when exposed to light. Commercial molybdate red pigments undergo photo-dissolution when exposed to simulated sunlight and exhibit lower photostability compared to lead chromate pigments such as chrome yellow. After 24 h of irradiation, the leaching rates of toxic lead and chromium from molybdate red pigments were 2.98 and 3.70 times higher, respectively, than those from chrome yellow pigments. The primary factor leading to decreased pigment photostability is the activation of pigment semiconductors facilitated by molybdenum doping. Molybdate red pigments exhibit a broader light absorption spectrum and more efficient separation and transfer of photogenerated charge carriers than chrome yellow pigments, boosting the photochemical activity. To the best of our knowledge, this is the first study to illustrate the doping effect on the photostability of commercial inorganic pigments and the consequent heavy metal leaching. Our results suggest that Mo doping reduces the photostability of lead chromate pigments, highlighting the potential elevated environmental risks associated with complex inorganic pigments.

Unraveling Lattice Dislocation‐Driven Energy Band Convergence Mechanism to Enhance Electrocatalytic Hydrogen Production in Alkaline Seawater

AbstractHydrogen evolution reaction (HER) from seawater electrolysis still faces challenges of low reactivity and chloride ions poison at the active sites, leading to reduced efficiency and stability of electrocatalysts. This study presents edge dislocation strategy aimed at inducing lattice strain in ferric oxide through Mo doping, consequently regulating the catalyst's band structure. Through in situ characterizations and DFT analysis, it is confirmed that lattice strain effectively modulates the band structure, intensifies the hybridization between Mo(d)‐Fe(d)‐O(p) orbitals, thereby accelerating the charge transfer rate of HER. Furthermore, band structure modulated by lattice strain enhances water adsorption capacity, reduces the adsorption energy of Cl−, and optimizes the hydrogen adsorption‐free energy (ΔGH*) for HER. Benefiting from above, the optimized 2%‐Mo‐Fe2O3 catalyst demonstrates HER activity and stability in alkaline seawater electrolysis comparable to that of commercial Pt/C. Additionally, the assembled electrolytic cell utilizing an anion exchange membrane (AEM) maintains long‐term stability for >100 h at 500 mA cm−2, showcasing a sustained catalytic effect.

Facile co-precipitation synthesis of nano-molybdenum-doped BaO nanoparticles and their physical characterization

Alkaline metal oxides have received significant attention recently due to their abundance, inherent conductivity, optical absorption, and thermal stability. Here, a straightforward co-precipitation method was employed to obtain both undoped BaO and Mo-doped BaO nanoparticles. Various techniques were used to characterize the synthesized nanoparticles’ structural, Raman spectral, optical, thermal, and electrical properties. X-ray diffraction (XRD) results revealed that Mo was successfully doped into tetragonal nanocrystalline BaO. The W-H plot showed that as Mo doping increases from 2 % to 6 %, the crystallite size grows while the lattice structure remains well-ordered with even strain distribution. Scanning electron microscopy (SEM) was used to examine its surface features. The purity and crystalline character of the samples were further confirmed via Raman spectroscopy, which shows that the peak intensity of the spectra increases with the increase of particle size owing to the rise in the force constant. UV spectroscopy was used to observe the energy band gap, which is found to decrease from 4.2 eV to 3.8 eV, and then it drops to 3.4 eV as the Mo content increases. This is reasonable because of the size-dependent attraction between metallic ions and conduction electrons. PL spectra concluded that Mo doping leads to the enhancement of the optical characteristics of BaO. Adding Mo to BaO also modifies the material’s thermal properties, potentially affecting its suitability for applications that require thermal durability. This finding exhibits that even slight doping of Mo4+ into BaO can significantly impact their structural, thermal, optical, and electrical characteristics. It enriches the existing body of knowledge of BaO nanoparticles and lays the foundation for its future research.

Promoting effect of interfacial hole accumulation on photoelectrochemical water oxidation in BiVO4 and Mo-doped BiVO4

Hole transfer at the semiconductor-electrolyte interface is a key elementary process in (photo)electrochemical (PEC) water oxidation. However, up to now, a detailed understanding of the hole transfer and the influence of surface hole density on PEC water oxidation kinetics is lacking. In this work, we propose a model for the first time in which the surface accumulated hole density in BiVO4 and Mo-doped BiVO4 samples during water oxidation can be acquired via employing illumination-dependent Mott-Schottky measurements. Based on this model, some results are demonstrated as below: (1) Although the surface hole density increases when increasing light intensity and applied potential, the hole transfer rate remains linearly proportional to surface hole density on a log-log scale. (2) Both water oxidation on BiVO4 and Mo-doped BiVO4 follow first-order reaction kinetics at low surface hole densities, which is in good agreement with literature. (3) We find that water oxidation active sites in both BiVO4 and Mo-doped BiVO4 are very likely to be Bi5+, which are produced by photoexcited or/and electro-induced surface holes, rather than VOx species or Mo6+ due to their insufficient redox potential for water oxidation. (4) Introduction of Mo doping brings about higher OER activity of BiVO4, as it suppresses the recombination rate of surface holes and increases formation of Bi5+. This surface hole model offers a general approach for the quantification of surface hole density in the field of semiconductor photoelectrocatalysis.

Mo-Induced Surface Reconstruction in Ni/Co-OOH Prickly Flower Clusters for Improving the Hydrogen Production in Alkaline Seawater Splitting.

Seawater electrolysis is the most promising technology for hydrogen production, in which surface reconstruction on the interface of electrode/electrolyte plays a crucial role in activating the catalytic reactions with a low activation energy barrier. Herein, an efficient Mo modifying NiCoMo prickly flower clusters electrocatalyst supported on nickel foam (Mo-doped Ni/Co-OOH prickly flower clusters) is obtained, which serves as an eminently active and durable catalyst for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) due to the surface reconstruction during the alkaline seawater electrolysis with ultralow overpotentials. It just requires a cell voltage of 1.52V to achieve the current density of 10mAcm-2 for water electrolysis along with robust durability over 30h. Mo doping effectively regulates the surface reconstruction of Ni/Co-OOH, which facilitates the adsorption of oxygen-containing intermediates on the active center, and the nonhomogeneous interface induces charge rearrangement for the catalytic process to improve efficiency, providing a new strategy for revealing the seawater electrolytic mechanism.

New Morphology Modifier Enables the Preparation of Ultra-Long Platinum Nanowires Excluding Mo Component for Efficient Oxygen Reduction Reaction Performance.

The structural tailoring of Pt-based catalysts into 1D nanowires for oxygen reduction reactions (ORR) has been a focus of research. Mo(CO)6 is commonly used as a morphological modifier to form nanowires, but it is found that it inevitably leads to Mo doping. This doping introduces unique electrochemical signals not seen in other Pt-based catalysts, which can directly reflect the stability of the catalyst. Through experiments, it is demonstrated that Mo doping is detrimental to ORR performance, and theoretical calculations have shown that Mo sites that are inherently inactive also poison the ORR activity of the surrounding Pt. Therefore, a novel gas-assisted technique is proposed to replace Mo(CO)6 with CO, which forms ultrafine nanowires with an order of magnitude increase in length, ruling out the effect of Mo. The catalyst performs at 1.24 A mgPt -1, 7.45 times greater than Pt/C, demonstrating significant ORR mass activity, and a substantial improvement in stability. The proton exchange membrane fuel cell using this catalyst provides a higher power density (0.7W cm-2). This study presents a new method for the preparation of ultra-long nanowires, which opens up new avenues for future practical applications of low-Pt catalysts in PEMFC.

Influence of Mo doping on the structural, Raman scattering, and magnetic properties of NiO nanostructures

In this work, the Ni1-xMoxO, (x = 0.000, 0.025, 0.050, 0.075, 0.100, and 0.150) nanoparticles were prepared employing the coprecipitation method. The X-ray diffraction (XRD) confirmed that all the samples have a face-centered cubic (FCC) structure with no secondary phases by the effect of the Mo-doping. The Mo-dopants yielded smaller crystallites, reaching a size of 9 nm with x = 0.150. The transmission electron microscope (TEM) images revealed agglomerated NiO nanoparticles with nearly spherical shapes varied to elliptical-like shapes upon increasing Mo concentration. The energy dispersive X-ray (EDX) confirmed the purity of the synthesized samples. The XPS analysis confirmed the valence states of the presented elements in the samples as Ni2+, Ni3+, Mo6+, and O2− ions. The XPS detected the reduction of the nickel and oxygen vacancies, by studying the ratio of Ni2+/Ni3+ and lattice oxygen (OL) to vacant oxygen (OV) peaks. The Raman analysis demonstrated the active vibrational modes of NiO, for all the samples, along with stretching Mo = O bonds for the doped samples. The Photoluminescence (PL) spectroscopy was employed to study the near band edge and deep level emissions, giving insight to the defect levels within the band gap. The PL affirmed the decrease of the oxygen vacancies upon Mo-doping. Besides, the magnetic hysteresis measurements at room temperature revealed the superparamagnetic contribution embedded in the antiferromagnetic matrix of NiO. The magnetization was tuned by Mo doping concentration, where it affected the saturation magnetization, coercivity, and remnant magnetization. Mo dopant can modify the magnetic property of NiO nanoparticles and can be a potential candidate in biomedical field and data storage applications.Graphical

Mitigating Jahn–Teller effect of MnO2 via charge regulation of Mn-local environment for advanced calcium storage

Manganese dioxide (MnO2) stands out as a prospective cathode material for calcium ion batteries (CIBs) owing to its elevated theoretical capacity and high operating voltage. Nevertheless, MnO2 with Jahn-Teller (J-T) twisted MnO6 octahedra experiences severe Mn dissolution during cycling, leading to the destabilization of the transition metal layer and resulting in poor cycling performance. In this work, Mo-substitution is purposely proposed to suppress the J-T effect in MnO2 for CIBs. The local charge of Mn is regulated by Mo doping, which enhances the electrical conductivity of MnO2 and suppresses the J-T distortion of the MnO6 octahedron. Meanwhile, density-functional theory (DFT) calculations manifest that Mo doping enhances the structural integrity of MnO2, making it difficult for Mn to escape from the MnO6 structure and inhibiting the dissolution of Mn. Accordingly, Mo-MnO2 demonstrates impressive rate capability (112 mAh g−1 at 1 A g−1) and excellent cycling stability, maintaining approximately 93.9 % capacity after 900 cycles at 1 A g−1. As a result, the introduction of heteroatoms through doping offers a novel design approach for the advancement of cathode materials for advanced CIBs.

Glass-ceramics and molybdenum doping synergistic approach for Nasicon-type solid-state electrolytes

Advancing energy density, enabling lithium metal anodes, and ensuring unparalleled safety and operational reliability in lithium batteries hinge on advancing inorganic solid-state electrolytes. To overcome current impediments, we present an innovative approach that integrates glass-ceramics with a pioneering new Nasicon strategy involving molybdenum doping. In the conducted study, a series of 14Li2O-9Al2O3-38TiO2-(39-x)P2O5-xMoO3 glasses, denoted as LATPMox, along with their corresponding glass-ceramics (LATPMox-GC), have exhibited a promising characteristic as solid electrolytes. X-ray diffraction (XRD) analysis confirms the formation of the novel Mo-doped Nasicon phases in the glass-ceramics, as validated by Rietveld refinement. Examination of the crystallization kinetic behavior of the glasses reveals a three-dimensional nucleation process with spherical particle growth, featuring an activation energy of 165 kJ mol−1. Transmission Electron Microscopy TEM characterization aligns crystallization behavior with crystallite and distribution within the glass matrix, resulting in a compact and dense microstructure. The structural properties of the resultant phases are examined through FT-IR, Raman spectroscopy, and TEM-SEAD analysis. Vickers indentation tests were employed to assess the microscopic fracture toughness, and both the glass and glass-ceramics materials demonstrated favorable mechanical performance. Optical characterization using UV–visible absorption highlights the reduction of Mo6+ to Mo5+, likely occupying tetrahedral sites within the crystalline lattice. Impedance spectroscopy measurement showcases the effective promotion of ionic conductivity following Mo doping, reaching a total conductivity value of 5.50 × 10−5 Ω−1 cm−1 along with a high lithium transference number of 0.99 at room temperature for LATPMo2.6-GC glass-ceramic. This value is larger than that of many other glass-ceramics as well as that of the well-known lithium phosphorous oxy-nitride LiPON solid electrolyte whose ionic conductivity at RT is around 2 × 10−6 Ω−1 cm−1.

Electronic and Atomic Structural Properties Associated with Enhanced Photodegradation Activity in Mo-Doped TiO2 Nanoparticles.

The efficacy and structural evolution of Mo-doped titania nanoparticles (MTNPs) as advanced photocatalysts for degrading methyl blue (MB) are investigated by X-ray absorption spectroscopy (XAS). The 3 wt % MTNP, characterized by uniform size and anatase structure, exhibits higher efficiency. The spectral analyses unveiled structural variations in the TiO6 octahedral structure and revealed an active site of the distorted square pyramidal structure symmetry (C4v). The in situ XAS spectra illustrate that MTNPs, particularly at 3 wt % doping, effectively enhanced the hole carriers in Ti 3d orbitals with a charge transfer to Mo 4d orbitals and impeded electron-hole pair merging, significantly enhancing the photodegradation under light illumination. This study deepens our understanding of the crucial role of Mo doping in optimizing TiO2 nanoparticle performance for efficient environmental remediation, showcasing the potential of MTNPs as sustainable photocatalytic materials.

A Bandgap-Tuned Tetragonal Perovskite as Zero-Strain Anode for Potassium-Ion Batteries.

PIBs are emerging as a promising energy storage system due to high abundance of potassium resources and theoretical energy density, however, progress of PIBs is severely hindered by structural instability and poor cycling of anode material during continual insertion and extraction of larger-sized K+. Hence, developing anode material with structural stability and stable cycling remains a great challenge. Herein, bandgap-tuned Mo-doped and carbon-coated lead titanate (CMPTO) with zero-strain K+ storage is presented as ultra-stable PIBs anode. Mo doping introduces narrowed bandgap and optimized crystal lattice for enhanced intrinsic electron and ion transfer. Demonstrated by in situ XRD characterizations, the crystal structure stays stable with unchanged peak positions, fully revealing zero-strain characteristic of CMPTO anode during potassium storage for stable cyclic capability. Ultimately, CMPTO anode achieved ultra-stable cycling performance of 7000 cycles at 500 mA g-1 with high capacity retention of 90% and considerable specific capacity of 130.9 mAh g-1 after 600 cycles at 100 mA g-1; with relatively large density, CMPTO realized eminent volumetric capacity of 1111.09 mAh cm-3 and ultra-long cycling life of 10000 cycles at 7041 mA cm-3. This work introduces a promisingly new route into developing anode materials with ultra-stable performance for PIBs.

Impact of Mo+2 addition and thermal annealing on the surface morphology, electrical transport properties and Mott's parameters of WO3 films for potential photonic devices

This work investigates the compositional dependence and thermal annealing of the morphological properties, electrical conductivity mechanisms and Mott's parameters of sprayed MoxW1-xO3 (x = 0, 0.05, 0.10 and 0,20) thin films. The prepared thin films were examined using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDX) and Fourier transform infrared spectroscopy (FTIR) techniques. In addition, the two-point probe method was used to calculate the electrical properties of MoxW1-xO3 thin films. The FTIR results revealed that; the tungsten hydroxyl bond (W-OH) and the surface hydroxyl group vibrated within the ranges of 1558.62–1645.56 cm−1 and, 3296.76 and 3424.34 cm−1, respectively. Furthermore, a prominent band in the spectrum spanning from 850 to 650 cm−1 represents the W-O-W bridge mode. The FE-SEM investigations found that the molybdenum (Mo) dopant caused significant changes in the surface morphology of the films. The EDX results showed that the percentages of the isotropic elements MoxW1-xO3 agreed well with those obtained by atomic weight. Studies of the conduction mechanism indicate that the transition temperature was approximately 393K. Corresponding to Mott's model, the conduction mechanism below this temperature was across the variable hopping conduction band near the Fermi level. The mechanism exhibited a cycle of localised states through activated thermionic emission above 393K. Mott parameters were also estimated in addition to barrier potential energies, trapping state energies, local state densities, and other variables. The results revealed that both temperature areas had a rise in ρo and ρ1 values during and after annealing. The ΔEo and ΔE1 values in each temperature area decreased as the Mo-ion concentration increased. Furthermore, the conversion temperature gradually reduced as Mo was added. Based on these properties, the study's overall findings indicate that MoxW1-xO3 is suitable for future photonic devices and optoelectronic applications.

MOF-derived Mo-doped Co3O4: A hierarchical yeast-like structure for superior carbon monoxide sensing

Carbon monoxide (CO) is one of the most dangerous gases owing to its dual threat, role in global warming, and severe impact on human health. Metal-organic framework (MOF) gas-sensing materials have drawn the interest of many different sectors due to their unique structural characteristics. This study used a solvothermal technique and subsequent annealing to create a hierarchical, yeast-shaped Mo-Co3O4 material from a Co-MOF precursor. The prepared materials have been employed in the development of a CO-detection gas sensor. Gas-sensing experiments revealed that Mo-Co3O4 exhibited significantly improved sensing capabilities compared to pure Co3O4. Notably, at 200 °C, 2 mol% Mo-Co3O4 showed high response levels of about 136 at 100 ppm CO concentrations, approximately 50.4 times higher than pure Co3O4. Furthermore, the Mo-doped material exhibited a low detection threshold, excellent reproducibility, long-term stability, good selectivity, and rapid response and recovery times (78.5/55.3 s). Introducing Mo dopants into the Co3O4 material and the hierarchical yeast-like nanostructure are responsible for these improvements in gas-sensing capability.