Molybdenum Doping Research Articles

Mo‐doped hollow Si3N4/SiC ceramic fiber composites for high temperature heat insulation and oxidation resistance

AbstractSilicon‐based ceramic composites have shown great potential in aerospace due to the favorable general properties. Compared with solid fiber materials, the hollow structure of silica‐based ceramic fiber shows better thermal insulation properties and has a wider range of applications. In this paper, Mo doped Si3N4/SiC ceramic fiber composites with hollow structure were obtained by coaxial electrospinning and polymer‐derived ceramics routine with polysilazane (PSN) as the precursor, MoSi2 powder as filler. The effects of pyrolysis temperature on the morphology and properties of the fibers were investigated. Benefitting from the preferred hollow structure, the obtained Mo doped hollow Si3N4/SiC ceramic fiber composites show favorable thermal insulation property (0.0367–0.0411 W·m−1·K−1 at room temperature). Besides, the doping of molybdenum provided satisfied oxidation resistant property due to the liquid phases formed during the oxidation process, which can effectively fill the cracks and voids generated by the thermal stresses, acting as a repairing agent and preventing further oxidation. Meanwhile, the oxide layer formed can also slow down the oxidation process by blocking oxygen molecules from penetrating further into the composites.

Addressing energy challenges: sustainable nano-ceramic electrolytes for solid-state lithium batteries by green chemistry

The escalating demand for high-performance, safe energy storage devices has propelled the advancement of solid-state battery (SSB) technology. SSBs can supplant traditional liquid electrolyte-based Li-ion batteries by offering higher theoretical capacities and enhanced safety through solid-state electrolytes. However, challenges like dendritic lithium growth and inadequate solid-solid interfaces impede their practical application. This study aims to overcome these barriers by enhancing the ionic conductivity of ceramic-based solid-state electrolytes by incorporating nanoscale multicomponent halides. Utilizing green chemistry principles, we synthesized composite electrolytes based on Li₃InCl₆, doped with fluorine (F), cerium (Ce), and molybdenum (Mo). Among these, the F-, Ce-, and Mo-doped Li₃InCl₆ electrolytes contributed uniquely to enhancing ionic conductivity. Mo-doping improved most substantially, reaching an average ionic conductivity modal value of 0.30 S cm⁻1 (Rangle 0.15,0.46) S cm−1;± 0.13 S cm⁻1, comparable to commercial liquid electrolytes. F doping enhanced lattice stability and facilitated Li⁺ ion mobility, while Ce doping improved structural integrity and reduced interfacial resistance. Comprehensive structural characterization confirmed the successful incorporation of dopants and favorable modification of the crystal lattice, facilitating enhanced Li⁺ ion mobility. Electrochemical performance evaluations using symmetrical half-cells demonstrated reduced charge transfer resistance and improved cycling stability, particularly in the Mo-doped variants. These findings underscore the effectiveness of molybdenum doping in mitigating interfacial resistance and promoting reliable ion transport in SSBs. Toxicity assessments revealed that using water as a solvent and natural extracts minimized the environmental footprint, aligning with sustainable synthesis practices. Our green nano-engineering approach not only advances the performance of solid-state electrolytes but also aligns with sustainable synthesis practices, paving the way for developing efficient and eco-friendly energy storage solutions. Additionally, our green nano-engineering approach was evaluated against traditional synthesis methods, demonstrating a 40% reduction in energy consumption and a 75% decrease in hazardous waste generation. This manuscript highlights the pivotal role of doped Li₃InCl₆ electrolytes in addressing current limitations of SSB technology, thereby contributing to the future of safe and high-capacity energy storage systems.

Enhancing efficiency of Cs2AgBiBr6 double perovskite solar cells through bandgap reduction by molybdenum doping

Enhancing efficiency of Cs2AgBiBr6 double perovskite solar cells through bandgap reduction by molybdenum doping

Modification of NiCo2S4 by molybdenum doping for boosting overall water splitting

Modification of NiCo2S4 by molybdenum doping for boosting overall water splitting

Molybdenum and Sulfur Doping To Create Active Sites and Regulate d-Band Centers of Ni-Mo-S Electrocatalysts for the Hydrogen Evolution Reaction.

Defining the active sites and further optimizing their activity are of great significance for enhancing the hydrogen evolution reaction (HER) performances, especially for inexpensive Ni-based catalysts doped with metals and nonmetal elements. This work reports the role of the incorporated molybdenum and sulfur in enhancing the HER activity of nickel. The prepared molybdenum and sulfur coincorporated Ni (NMS) electrocatalysts exhibit excellent HER performance, with an overpotential and Tafel slope of 77.0 mV (10 mA·cm-2) and 64.4 mV·dec-1, respectively, because of the large electrochemically active surface area, quick reaction kinetics, and charge-transfer capability. The theoretical calculation results reveal that the incorporated Mo atoms play the role of reaction sites, and the introduced S atoms can further enhance the activity of Mo atom. The high HER activity of the Mo atom can be attributed to the regulated d-band center by optimizing the composition of NMS, which tunes the interaction between Mo and intermediate species. The elucidated mechanism can make it possible to design Ni-based electrocatalysts doped with metals and nonmetals for efficient hydrogen evolution.

Tailoring Urchin‐Like Nb2O5 Nanostructures with Molybdenum Doping to Enhance Adsorption Efficiency and Selectivity toward Cationic Dyes in Wastewater Treatment

Effective wastewater treatment is essential for mitigating organic pollutants, such as dyes and antibiotics. In this study, the enhancement of niobium pentoxide (Nb2O5) nanostructures via molybdenum (Mo) doping to improve adsorption efficiency, selectivity, and reusability is investigated. Mo doping, successfully confirmed by X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy, demonstrates effective integration into the Nb2O5 lattice, inducing lattice expansion and modifying its structural and surface properties. Mo‐doped Nb2O5 exhibits increased adsorption capacities for methylene blue (MB) and crystal violet (CV), improving from 26.9 and 17.0 (undoped) to 35.4 and 44.8 mg g−1, respectively. In contrast, the capacities for Congo red and tetracycline decrease from 31.6 and 36.8 to 16.7 and 32.0 mg g−1, respectively. Isotherm modeling shows Langmuir‐type adsorption with maximum capacities of 48.6 mg g−1 for MB and 52.4 mg g−1 for CV. Point of zero charge analysis indicates improved cationic dye selectivity, while recyclability tests demonstrate that Mo‐doped Nb2O5 can retain over 96% of its capacity after five cycles. In thermodynamic studies, an exothermic and spontaneous process is revealed, with pseudo‐second‐order kinetics confirming chemisorption as the dominant mechanism. In these findings, Mo‐doped Nb2O5 is established as a highly effective material for treatment applications.

Tailoring electronic structure to enhance the ammonium-ion storage properties of VO2 by molybdenum doping toward highly efficient aqueous ammonium-ion batteries

The electronic structure of tunnel-like VO2 is tailored by Mo doping (VO2-Mo). At 0.1 A g−1, VO2-Mo exhibits a specific capacity of 370 mA h g−1, surpassing that of VO2 (about 232 mA h g−1) and V-based materials reported for NH4+ storage.

Synthesis of doped titanium-based lithium adsorbents with excellent stability and adsorption performance by solid state reactions

Synthesis of doped titanium-based lithium adsorbents with excellent stability and adsorption performance by solid state reactions

Binder-Less Molybdenum Doped CoO Based Integrated Electrodes Fabricated by Electric Discharge Corrosion for High-Efficiency Supercapacitors

Due to its low cost, natural abundance, non-toxicity, and high theoretical capacitance, cobalt oxide (CoO) stands as a promising candidate electrode material for supercapacitors. In this study, binder-less molybdenum doped CoO (Mo@CoO) integrated electrodes were one-step fabricated using a simple electric discharge corrosion (EDC) method. This EDC method enables the direct synthesis of Mo@CoO active materials with oxygen vacancy on cobalt substrates, without any pre-made templates, conductive additives, or chemicals. Most importantly, the EDC method enables precise control over the discharge processing parameter of pulse width, which facilitates tailoring the surface morphologies of the as-prepared Mo@CoO active materials. It was found that the fabricated Mo@CoO based symmetric supercapacitor prepared by a pulse width of 24 μs (Mo@CoO-SCs24) achieved a maximum areal capacitance 36.0 mF cm−2 (0.15 mA cm−2), which is 1.83 and 1.97 times higher than that of Mo@CoO-SCs12 and Mo@CoO-SCs36. Moreover, the Mo@CoO-SCs24 devices could be worked at 10 V s−1, which demonstrates their fast charge/discharge characteristic. These results demonstrated the significant potential of the EDC strategy for efficiency fabricating various metal oxide binder-less integrated electrodes for various applications, like supercapacitors, batteries and sensors.

Influence of Molybdenum Addition on the Structure, Mechanical Properties, and Cutting Performance of AlTiN Coatings

Though AlTiN coating has been intensively studied, there is still a need to develop AlTiN coating to meet the growing demand of industrial machining. One effective way to improve the performance of AlTiN coating is by adding alloying elements. In this study, AlTiN and AlTiMo coatings were deposited using multi-arc ion plating to investigate the influence of molybdenum addition on the structure, mechanical properties, and cutting performance of AlTiN coatings. Spherical droplets formed on the surfaces of both coatings, with the AlTiMoN coating exhibiting more surface defects than the AlTiN coating. The grazing incidence X-ray diffraction results revealed the formation of an (Al,Ti)N phase formed in the AlTiN and AlTiMoN coatings. Molybdenum doping in the AlTiMoN coating slightly reduced the grain size. Both coatings exhibited excellent adhesion to the substrate. The hardness (H), elastic moduli (E), H/E, and H3/E2 ratios of the AlTiMoN coating were higher than those of the AlTiN coating. The improvement in the mechanical properties was attributed to grain refinement and solution strengthening. Molybdenum doping improved the tribological properties and cutting performance of the AlTiN coatings, which was ascribed to the formation of MoO3 as a solid lubricant. These results show a path to increase the performance of AlTiN coating through molybdenum addition and provide ideas for the application of AlTiMoN coatings for cutting tools.

Tailoring Ni-Rich Cathode Properties with Mo Doping for Next-Generation Li-Ion Batteries

Among battery components, cathode chemistry is a defining feature because it primarily determines both cost and performance. Enhancing the long-term cycling stability of Ni-rich layered cathode materials is crucial for high-energy-density applications in electric vehicles. However, the intrinsic instability of these Ni-rich layered cathode materials, which increases with increasing Ni content, limits their commercial use.1 Doping is a promising strategy to improve stability and performance. However, improving cycling performance through cathode material doping is challenging and requires the careful tuning of the doping parameters and conditions.2 Among the various dopants, Mo is highly effective in refining cathode morphology across a broad range of lithiation temperatures, enhancing the resistance of cathode particles to mechanical damage and improving their stability during repeated cycling. Hearin, we investigate the impact of molybdenum (Mo) doping on Ni-rich NCMA cathodes, examining how varing Mo content and lithiation temperatures affect material properties. To evaluate the effect of Mo as a dopant, we focused on the morphological properties and crystallinity of Mo-doped Ni-rich NCMA94 cathode materials. The results show that optimal Mo doping improves cathode morphology and crystallinity, leading to better electrochemical performance.3 Mo-doped NCMA94 cathodes with refined primary particle size and high crystallinity demonstrate superior capacity and cycling stability. This study provides insights into optimizing doping parameters for advanced Ni-rich cathode materials, supporting long cycle life in next-generation Li-ion batteries.

Effect of Molybdenum Concentration and Deposition Temperature on the Structure and Tribological Properties of the Diamond-like Carbon Films

Two series of non-hydrogenated diamond-like carbon (DLC) films and molybdenum doped diamond-like carbon (Mo-DLC) films were grown on the silicon substrate using direct current magnetron sputtering. The influence of molybdenum doping (between 6.3 and 11.9 at.% of Mo), as well as the deposited temperature (between 185 and 235 °C) on the surface morphology, elemental composition, bonding microstructure, friction force, and nanohardness of the films, were characterized by atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and a nanoindenter. It was found that the increase in the metal dopant concentration led to a higher metallicity and graphitization of the DLC films. The surface roughness and sp3/sp2 ratio were obtained as a function of the Mo concentration and formation temperature. The nanohardness of DLC films was improved by up to 75% with the addition of Mo. Meanwhile, the reduction in the deposition temperature decreased the nanohardness of the DLC films. The friction coefficient of the DLC films was slightly reduced with addition of the molybdenum.

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

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

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

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

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

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

Enhancing thermoelectric performance in flexible fabric-based Mo-doped CuAl2O4: Insights into carrier type modification and electrical conductivity optimization

Enhancing thermoelectric performance in flexible fabric-based Mo-doped CuAl2O4: Insights into carrier type modification and electrical conductivity optimization

Boosting the Electrical Transfer by Molybdenum Doping for Robust and Flexible NiSe-Based Supercapacitor.

NiSe is a promising electrode material for enhancing the energy density of supercapacitors, but it faces challenges such as sensitivity to electrolyte anions, limited specific capacity, and unstable cycling. This study employs a strategy of metal atom doping to address these issues. Through a hydrothermal reaction, Mo-doped NiSe demonstrates significant improvement in electrochemical performance, exhibiting high capacity (799.90Cg-1), splendid rate performance, and excellent cyclic stability (90% capacity retention). The introduction of Mo induces charge redistribution in NiSe, leading to a reduction in the band gap. Theoretical calculation reveals that Mo doping can effectively enhance the electrical conductivity and the adsorption energy of NiSe. A flexible printed hybrid Mo-doped NiSe-based supercapacitor is fabricated, demonstrating superior electrochemical performance (367.04mFcm-2) and the ability to power timers, LEDs, and toy fans. This research not only deepens the understanding of the electrochemical properties of metal-doped NiSe but also highlights its application potential in high-performance supercapacitors.

Investigating the effect of Mo doping on structural and ferroelectric properties of BaTiO3 using electron microscopy

Investigating the effect of Mo doping on structural and ferroelectric properties of BaTiO3 using electron microscopy

Cumulative effect of molybdenum doping and nitrogen atmosphere on the properties of vanadium oxycarbide cermets with iron binder

Cumulative effect of molybdenum doping and nitrogen atmosphere on the properties of vanadium oxycarbide cermets with iron binder

A novel electrode for simultaneous detection of multiple heavy metal ions without pre-enrichment in food samples

A novel electrode for simultaneous detection of multiple heavy metal ions without pre-enrichment in food samples