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The nitrogen‐rich molybdenum nitrides (N/Mo > 1) are promising for water electrolysis due to their increased activity and antioxidant ability. However, a higher temperature is needed in the usual synthesis for introducing more N, leading to the formation of large particles and the difficulty in controlling the morphology, thus limiting their catalytic performance. Here, a new strategy is reported based on the synergy of internal/external N sources (INS and ENS) toward Mo5N6‐based catalysts at a decreased temperature of 450 °C. The PMo12 clusters and Ni2+ (Co2+) are first combined with 2‐methylimidazole/melamine (INS) to give a flower‐like assembly. The subsequent pyrolysis under NH3 flow (ENS) gives the flowers composed of small Mo5N6/Ni (Co) heterojunctional particles that can expose more surface sites with an optimized electronic structure. The Mo5N6/Ni exhibits good HER activity close to Pt/C, and Mo5N6/Co shows superior OER performance to IrO2. The Mo5N6/Ni||Mo5N6/Co cell drives overall water splitting (OWS) at a low voltage of 1.397/1.74 V to achieve a current density of 10/100 mA cm−2 in the 1.0 M KOH. An anion exchange membrane water electrolyzer (AEMWE) based on the catalysts can achieve a current density of 450 mA cm−2 at 1.8 V with a long‐term stability of 120 h. [ABSTRACT FROM AUTHOR]

Molybdenum trioxide (MoO3) possesses high energy density but often suffers from poor electrical conductivity and limited cycling stability when used as a sodium‐ion battery (SIB) anode. To address these issues, the construction of （Molybdenum trioxide‐Molybdenum disulfide）MoO3‐MoS2 heterostructures has proven effective in enhancing electronic conductivity, ion diffusion properties, and structural stability. Guided by the density functional theory (DFT) calculations, which predict favorable Na+ diffusion and adsorption properties, nanorod‐like MoO3‐MoS2 heterostructures are synthesized using a two‐step method. Benefiting from the synergistic effects of the heterostructure and nanosized morphology, the resulting MoO3‐MoS2 electrode exhibits outstanding rate performance (316 mA h g−1 at 10 A g−1) and long‐lasting cycling stability (286 mA h g−1 after 2300 cycles at 5 A g−1) as an SIB anode. In situ XRD measurements reveal that the ultrahigh specific capacity of MoO3‐MoS2 is attributed to the synergistic intercalation‐conversion storage of MoO3 and MoS2. In the pursuit of meeting commercialization requirements, electrodes with adjustable mass loading are also prepared using 3D printing, showcasing the high areal capacity characteristics of the SIBs. This study not only provides theoretical insights into expanding the use of heterojunction materials as SIB anodes but also demonstrates the significant potential for creating high‐energy‐density and cost‐effective SIBs. [ABSTRACT FROM AUTHOR]

Strong metal‐support interaction (SMSI) between transition metal nanoparticles and carbon matrix offers significant structure advantages due to the ability to modulate the electronic structure of metal nanoparticles, increase the density of active sites, and improve the conductivity of catalysts. Here, ultrafine nanoparticles of metallic molybdenum compounds (MoP, Mo2C, and MoS2) strongly coupled with mesoporous carbon CMK‐5 are synthesized. The confinement growth of nanoparticles in the pores of CMK‐5 produces encapsulated nanoparticles, affording facilitated electron transfer, and enhancing the HER activity induced by the SMSI effect. The hierarchical nanostructure and strong electronic interactions between the carbon substrate and molybdenum‐based nanoparticles allow efficient mass/electron transport between the carbon substrate and molybdenum‐based nanoparticles, improving the catalytic hydrogen evolution reaction (HER) activity. The effective electron exchange between the Mo species and the CMK‐5 support is studied by X‐ray photoelectron spectroscopy (XPS) measurement, confirming the presence of the SMSI effect. The resulting MoP/CMK‐5 catalyst exhibits outstanding HER performance in alkaline (65 mV@10 mA cm−2), acidic (123 mV@10 mA cm−2), and simulated seawater electrolytes (103 mV@10 mA cm−2), making it one of the most promising catalysts reported for HER. This work provides guidance on designing high‐performance electrocatalysts with SMSI for the enhancement of the electrochemical reaction. [ABSTRACT FROM AUTHOR]

A fully biodegradable, ultra‐sensitive, and soft strain sensor is pivotal for temporary, real‐time monitoring of microdeformations, crucial in disease diagnosis, surgical precision, and prognosis of muscular, and vascular conditions. Nevertheless, the strain sensitivity of previous biodegradable sensors, denoted by gauge factor (GF) up to ≈100, falls short of requirements for complex biomedical monitoring scenarios, specifically monitoring cardio‐cerebrovascular diseases with microscale variations in vascular surface strain. Here, a fully biodegradable, ultra‐sensitive crack‐based flexible strain sensor is introduced achieving GF of 1355 at 1.5% strain through integration of molybdenum (Mo) film, molybdenum trioxide (MoO3) adhesion layer, and polycaprolactone (PCL) substrate. Analysis of crack morphology of biodegradable thin‐film metals, including Mo, tungsten (W), and magnesium (Mg), reveals material‐dependent sensitivity and repeatability of crack‐based strain sensors. The effect of the adhesion layer and polymer substrate is also investigated. Overall morphological studies on the sensor present a comprehensive understanding of metal film cracking behavior and corresponding performance characterization, showing significant potential for highly sensitive sensors. A hybrid membrane composed of candelilla wax (Cw), beeswax (Bw), and polybutylene adipate‐co‐terephthalate (PBAT) is introduced to provide hydrophobic, yet flexible encapsulation. In vivo, short‐term (≈3 days) monitoring of vascular pulsatility underscores the potential of the sensing tool for rapid, accurate, and temporal disease diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogen evolution and (S2−) recycling present promising strategies for cost‐effective hydrogen production and simultaneous removal of environmental pollutants. However, the advancement of this technology is hindered by the limited availability of affordable, efficient, and stable catalysts. Herein, the study synthesizes ultrafine ruthenium (Ru) nanoclusters on a substrate of iron molybdenum sulfide (FeMo‐S) nanosheets, creating a new heterointerface catalyst (FeMo‐S/Ru) for the hydrogen evolution reaction (HER) and sulfion oxidation reaction (SOR). Experimental and theoretical calculations suggest that strong electron interactions between Ru nanoclusters and FeMo‐S substrate, optimizing *H adsorption and promoting HER activity on one side while facilitating the production and adsorption of sulfur intermediates on the other side, effectively catalyzing SOR. Additionally, the assembled electrocatalytic coupling system with FeMo‐S/Ru displays an ultralow cell voltage of 0.57 V at 100 mA cm−2, achieving high Faradaic efficiencies (>96%) for H2 production, while also exhibiting remarkable durability over 1 month (838 h). This work paves the way for the development of highly efficient and durable supported catalysts, enabling energy‐saving hydrogen production and environmentally friendly sulfion recycling. [ABSTRACT FROM AUTHOR]

Sluggish redox kinetics and severe polysulfide shuttling are major hurdles for the commercialization of lithium–sulfur (Li–S) batteries. Transition‐metal compound catalysts offer a promising solution by providing excellent polysulfide adsorption capabilities, outstanding catalytic activities, and homogeneous nucleation control of Li2S2/Li2S. The electronic structure of transition‐metal sites in catalysts can also be fine‐tuned through bi‐metallic coupling, which can further improve the catalytic activities. In this study, bi‐metallic nickel molybdenum phosphide is co‐synthesized with Li2S and carbon through a carbothermal reduction process, forming a cathode composite (Li2S @ NixMoyPz @ C). This process is not only advantageous for large‐scale manufacturing due to its simplicity, but also ensures homogeneous integration and distribution of the catalyst within the cathode composite. Furthermore, applying Li2S as an active material allows the creation of an anode‐free cell configuration, enhancing the overall cell energy density. The anode‐free cell with the Li2S @ NixMoyPz @ C composite cathode demonstrates an outstanding capacity retention of 50% over 300 cycles at a negative‐to‐positive capacity (N/P) ratio of 1. Additionally, the bi‐metallic phosphide integrated Li2S cathode composite delivers a remarkable anode‐free pouch cell performance of 703 mA h g−1 (on Li2S basis) under the challenging conditions of an E/Li2S ratio of 4.5. [ABSTRACT FROM AUTHOR]

2D materials have attracted attention in the field of neuromorphic computing applications, demonstrating the potential for their use in low‐power synaptic devices at the atomic scale. However, synthetic 2D materials contain randomly distributed intrinsic defects and exhibit a stochasitc forming process, which results in variability of switching voltages, times, and stat resistances, as well as poor synaptic plasticity. Here, this work reports the wafer‐scale synthesis of highly polycrystalline semiconducting 2H‐phase molybdenum ditelluride (2H‐MoTe2) and its use for fabricating crossbar arrays of memristors. The 2H‐MoTe2 films contain small grains (≈30 nm) separated by vertically aligned grain boundaries (GBs). These aligned GBs provide confined diffusion paths for metal ions filtration (from the electrodes), resulting in reliable resistive switching (RS) due to conductive filament confinement. As a result, the polycrystalline 2H‐MoTe2 memristors shows improvement in the RS uniformity and stable multilevel resistance states, small cycle‐to‐cycle variation (<8.3%), high yield (>83.7%), and long retention times (>104 s). Finally, 2H‐MoTe2 memristors show linear analog synaptic plasticity under more than 2500 repeatable pulses and a simulation‐based learning accuracy of 96.05% for image classification, which is the first analog synapse behavior reported for 2D MoTe2 based memristors. [ABSTRACT FROM AUTHOR]

The more sluggish kinetics of hydrogen evolution catalysts in base as compare to that in acid to some degree restricts hydrogen production performance of hydroxide exchange membrane electrolyzers, especially when using earth‐abundant catalysts. Here a ternary nickel–copper–molybdenum hydrogen evolution catalyst is reported that exhibits ≈5 times higher turnover frequency than without copper doping. The X‐ray absorption near‐edge structure and valence band spectrum demonstrate that the light doping of copper into nickel–molybdenum alloy modulates the electronic structure and downshifts the d‐band center, resulting in accelerated hydrogen desorption, as consolidated by H2 temperature programmed desorption and theoretical calculation. An electrolyzer employing this cathode catalyst and a nickel–iron anode, gives a current density of 1.7 A cm−2 at 2.0 V with a pure‐water feed through the anode, which outperforms the 2025 target proposed by the United States Department of Energy, and even is operated continuously for over 1000 h with a decay rate of as low as 0.5 mV h−1. Post‐mortem analysis discloses that hydroxide exchange ionomer migration is one of the key factors affecting long‐term durability. This work demonstrates the feasibility of a low‐cost, water‐fed hydroxide exchange membrane electrolyzer achieving industrial‐level performance and lifetime. [ABSTRACT FROM AUTHOR]

With the persistent downscaling of integrated circuits, molybdenum (Mo) is currently considered a potential replacement for copper (Cu) as a material for metal interconnects. However, fabricating metal nanostructures with critical dimensions of the order of 10 nm and below is challenging. This is because the very high density of grain boundaries (GBs) results in highly non‐uniform surface profiles during direct wet etching. Moreover, wet etching of Mo with conventional aqueous solutions is problematic, as products of Mo oxidation have different solubility in water, which leads to increased surface roughness. Here, a process is shown for achieving a stable and uniform soluble surface layer of Mo oxide by wet oxidation with H2O2 dissolved in IPA at −20 °C. The oxide layer is then selectively dissolved, and by repeating the oxidation and dissolution multiple times, a uniform etch profile is demonstrated with a fine control over the metal recess. Ultimately, this presents a method of precise and uniform wet etching for Mo and other metals needed to fabricate complex nanostructures that are critical in developing next‐generation electronic devices. [ABSTRACT FROM AUTHOR]

Solution‐processed chalcopyrite thin film solar cells have made great progress but still lag behind the vacuum‐based ones due to inferior absorber quality and non‐ideal interfaces. Here, plasma treatment of the molybdenum (Mo) substrate is reported to modify the back interface and improve the efficiency of solution‐processed copper indium sulfoselenide (CuIn(S,Se)2, CISSe) solar cells. The results show plasma treatment oxides the surface Mo/MoO2 to high oxidation oxides MoO3‐x (0 ≤ x < 1). The higher surface polarity greatly improves the wettability of the substrate to the precursor solution and results in formation of more compact and uniform precursor film, which grows to void‐free larger grains absorber film with better adhesion to the substrate. In addition, the much higher chemical stability of MoO3‐x than Mo significantly reduces the thickness of high resistive MoSe2 layer. The improved absorber quality and back interface property decreases charge carrier recombination in the absorber and back contact interface, resulting in 14.53% efficiency solution‐processed CISSe solar cell, which is improved by 13% compared to device without plasma treatment. [ABSTRACT FROM AUTHOR]

In crystalline silicon (c‐Si) solar cells, the hole transport layer (HTL) made of high oxygen content MoOx (x > 2.85, H‐MoOx) evaporating from molybdenum trioxide is not ideal due to low optical bandgap and interface reaction effects. This limits the power conversion efficiency (PCE) and stability of c‐Si solar cells. To improve this, low oxygen content MoOx (x < 2.85, L‐MoOx) with a wide bandgap of 3.87 eV, deposited using molybdenum dioxide (MoO2), is explored and implemented. The c‐Si/SiOx (FGA, forming gas annealing)/L‐MoOx heterojunction has a low contact resistivity of ≈15.06 mΩ cm2, which is almost one order of magnitude lower than that of c‐Si/SiOx(FGA)/H‐MoOx heterojunction. Using L‐MoOx as the HTL, a c‐Si solar cell based on the SiOx passivation layer shows a fill factor of 84.38% and PCE of 21.75%, representing the highest efficiency for MoOx‐based p‐type c‐Si solar cells. Scanning transmission electron microscopy results show that the L‐MoOx HTL effectively enhances the stability of c‐Si solar cells when exposed to air by reducing Ag and Si element diffusion into MoOx. This successful preparation of efficient and stable MoOx HTL films, while preserving their field‐effect passivation ability, provides valuable insights into the development of high‐performance HTL. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium–sulfur (RT Na–S) batteries have emerged as a promising candidate for next‐generation scalable energy storage systems, due to their high theoretical energy density, low cost, and natural abundance. However, the practical applications of these batteries are hindered by the notorious shuttle effect of soluble sodium polysulfides (NaPSs) and sluggish reaction kinetics, which result in fast performance loss. To address this issue, recent studies have reported impressive achievements of transition metal nanoparticles/single atoms/cluster/compounds (TM)‐based host materials with strong adsorption and catalyzation to NaPSs. These materials can significantly improve the electrochemical performance of RT Na–S batteries. In this review, the recent progress on TM‐based host materials for RT Na–S batteries, including iron (Fe)‐, cobalt (Co)‐, nickel (Ni)‐, molybdenum (Mo)‐, titanium (Ti)‐, vanadium (V)‐, manganese (Mn)‐, and other TM‐based materials are summarized. The design, fabrication, and properties of these host materials are comprehensively summarized and systematically analyzed the underlying chemical inhibition and electrocatalysis mechanism between NaPSs and TM‐based catalytic materials. At last, the challenges and prospects for designing efficient TM‐based catalytic materials for high‐performance RT Na–S batteries are discussed. [ABSTRACT FROM AUTHOR]

Advancing green hydrogen production technologies relies heavily on the development of highly efficient and durable bifunctional catalysts for overall water splitting. Herein, this study reports the ruthenium‐modified hollow cubic molybdenum‐cobalt phosphide (Ru‐MoCoP) as exceptional performance electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Theoretical calculations and experimental results indicate that the incorporation of Ru not only serves as an efficient active site, but also adjusts the electronic structure and improves the reactivity of the original sites, as well as generates more phosphorus vacancies, which improves the electrical conductivity and exposes more active sites. Benefiting from the advantages triggered by the incorporation of Ru mentioned above, the Ru‐MoCoP delivers low overpotentials of 55 and 240 mV at 10 mA cm−2 for HER and OER, respectively. Furthermore, the electrolyzer assembled with Ru‐MoCoP achieves a current density of 50 mA cm−2 at 1.6 V and can be operated stably for 150 h. Notably, the assembled two‐electrode system can be powered by a single commercial AA battery, accompanied with evident gas bubble evolution. This research proposes a promising strategy for the development of highly efficient bifunctional phosphide catalysts, aiming to achieve efficient energy conversion in a wide range of industrial applications. [ABSTRACT FROM AUTHOR]

Lithium–iodine (Li–I2) batteries with ideal discharge potential plateau and abundant iodine resources have attracted considerable attention. However, the poor electrical conductivity of iodine with high solubility in organic electrolytes, and the Li dendrite issue have severely limited the practical application of Li–I2 batteries. Herein, this work demonstrates that the bifunctionalization of polypropylene (PP) separator with molybdenum clusters on N, O codoped graphene nanosheets (Mo‐rGO@PP) is efficient to promote the reversible redox reactions of polyiodides to suppress the shuttle effect, and enhance the Li affinity for the uniform Li plating/stripping. Typically, the Li symmetric battery assembled with Mo‐rGO@PP separator exhibits an ultralong lifespan of >2000 h with a low overpotential of <25 mV at 10 mA cm−2. With such a separation effect to effectively suppress the polyiodide shuttle and dendrite growth, the Li–I2 battery delivers a long cycle life of over 6000 cycles with a reversible capacity of 170 mAh g−1 at 10 C. With deep insights into the ion flux and redox regulation, this work demonstrates the promising advances via the separation effect for developing high‐performance redox batteries. [ABSTRACT FROM AUTHOR]

0D nanomaterials with high efficiency of atom utilization possess extraordinary tunability over bulk materials. Precise reconstruction of atoms in a 0D nanoparticle toward tuning of crystalline phases and defects is highly desirable but remains a grand challenge. In this study, a crystallization rate‐controlled strategy is reported to achieve controllable reconstruction of atoms in situ, which inducts a series of monodisperse 0D molybdenum carbide nanoparticles (MoxC NP) that anchor on a carbon matrix with adjustable crystalline phases and atom vacancies. Aberration‐corrected transmission electron microscopy, electron paramagnetic resonance technique, density functional theory calculation, and electron holography jointly reveal the atomic reconstruction process and confirm its remarkable effects of optimizing the local electronic states and enhancing the heterointerface interactions. As a result, the optimized MoC/Mo2C heterostructure on the carbon matrix is shown to enable the promoted dielectric response and generate more than 90% absorption of lower‐frequency microwaves (the current 5th‐generation communication band). The control of atomic reconstruction may provide an effective pathway for unlocking tunable dielectric properties of 0D nanomaterials toward various technological applications. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenide (TMDC) nanotubes complement the field of low‐dimensional materials with their quasi‐1D morphology and a wide set of intriguing properties. By introducing different transition metals into the crystal structure, their properties can be tailored for specific purpose and applications. Herein, the characterization and a subsequent preparation of single‐nanotube field emission devices of MoxWx‐1S2 nanotubes prepared via the chemical vapor transport reaction is presented. Energy‐dispersive X‐ray spectroscopy, Raman spectroscopy, and X‐ray diffraction indicate that the molybdenum and tungsten atoms are randomly distributed within the crystal structure and that the material is highly crystalline. High resolution transmission electron microscopy and electron diffraction (ED) patterns further corroborate these findings. A detailed analysis of the ED patterns from an eight‐layer nanotube reveal that the nanotubes grow in the 2H structure, with each shell consists of one bilayer. The work function of the nanotubes is comparable to that of pure MoS2 and lower of pure WS2 NTs, making them ideal candidates for field emission applications. Two devices with different geometrical setup are prepared and tested as field emitters, showing promising results for single nanotube field emission applications. [ABSTRACT FROM AUTHOR]

Sodium‐based dual‐ion batteries (SDIBs) have attracted increasing research interests in energy storage systems because of their advantages of high operating voltage and low cost. However, exploring desirable anode materials with high capacity and stable structures remains a great challenge. Here, an elaborate design is reported, starting from well‐organized MoSe2 nanorods and introducing metal‐organic frameworks, which simultaneously forms a bimetallic selenide/carbon composite with coaxial structure via electronegativity induction. By rationally adjusting the vacancy concentration and combining heterostructure engineering, the optimized MoSe2‐x/ZnSe@C as anode material for Na‐ion batteries achieves rapid electrochemical kinetics and satisfactory reversible capacities. The systematic electrochemical kinetic analyses combined with theoretical calculations further unveil the synergistic effect of Se‐vacancies and heterostructure for the enhanced sodium storage, which not only induces more reversible Na+ storage sites but also improves the pseudocapacitance and reduce charge transfer resistance, thereby providing a great contribution to accelerating reaction kinetics. Furthermore, the as‐constructed SDIB full cell based on the MoSe2‐x/ZnSe@C anode and the expanded graphite cathode demonstrates impressively excellent rate performance (131 mAh g−1 at 4.0 A g−1) and ultralong cycling life over 1000 cycles (100 mAh g−1 at 1.0 A g−1), demonstrating its practical applicability in a wide range of sodium‐based energy storage devices. [ABSTRACT FROM AUTHOR]

The development of advanced nanomaterials is urgent for electrocatalytic energy conversion applications. Recently, 2D nanomaterial‐derived heterogeneous electrocatalysts have shown great promise for both fundamental research and practical applications owing to their extremely high surface‐to‐volume ratio and tunable geometric and electronic properties. Because of their unique electronic structure and physicochemical properties, molybdenum (Mo)‐based 2D nanomaterials are emerging as one of the most attractive candidates among the nonprecious materials for electrocatalysts. This review provides a comprehensive overview of the recent advances in the synthesis and modulation of 2D Mo compounds for applications in electrocatalytic energy conversion. The categories based on different compositions and corresponding synthetic approaches of 2D Mo compounds are first introduced. Subsequently, various atomic/plane/synergistic engineering strategies, along with catalytic optimization in the electrochemical process that involves the cycles of water, carbon, and nitrogen, are discussed in detail. Finally, the current challenges and future opportunities for the development of 2D Mo‐based electrocatalysts are proposed with the goal of shedding light on these promising 2D nanomaterials for electrocatalytic energy conversion. [ABSTRACT FROM AUTHOR]

When it is asked, "where can refractory metals be used?," the possible shortest answer is, "where cannot they be used?" The uses of refractory‐metal‐based compounds in research and industry are too many to be enumerated; nevertheless, some outstanding examples are briefly mentioned here. Essentially, chalcogenide forms of refractory metals are preferred in the fabrication of high‐performance structures. Therefore, expanding the current studies that usually focus on tungsten‐ and molybdenum‐based structures to other materials may open new opportunities. Moreover, research on ternary and quaternary structures can also be a keystone in creating high‐performance products. The rationale of the present review is to give a brief overview of the recent history of refractory‐metal‐based chalcogenides (RMCs). Initially, the framework is confined to the general design and approaches for the synthesis of refractory metal chalcogenides. The assay is continued by extending with characteristic features of materials from crystalline properties to thermoelectric attributes and examining device fabrication processes. Taken together, the device fabrication part where RMCs are mainly used is extensively focused upon. Finally, outlook and future perspectives are given on the design and construction of RMCs to enable future inspiration and innovation. [ABSTRACT FROM AUTHOR]

Semiconducting 2D transition metal dichalcogenides (2D TMDs) with tunable electronic properties are a fundamental prerequisite for the development of next generation advanced electronic/optoelectronic devices. However, controllable and quasi‐continuous tuning carrier polarity of monolayered MoS2 ranging from intrinsic n‐type to p‐type via ambipolarity still remains a challenge. Herein, quasi‐continuous tailoring of carrier polarity of monolayered MoS2 through substitutional doping of molybdenum (Mo) with vanadium (V) atoms is presented. Atomic distribution in real space characterized by spherical aberration‐corrected scanning transmission electron microscopy (Cs‐STEM) reveals that the V atoms randomly substitute Mo in monolayered MoS2, and its doping concentration can be tuned in a wide range from 0.7 to ≈10 at.%. Electrical measurements confirm that the carrier polarity of the monolayered MoS2 can be tuned from intrinsic n‐type to p‐type via ambipolarity depending on the V doping degree, consistent with the density functional theory calculations. Moreover, this doping strategy is demonstrated to extend to other monolayered 2D TMDs by using MoSe2 as a model material, owing to a good universality. [ABSTRACT FROM AUTHOR]

Layered transition metal dichalcogenides (TMDs) are promising candidates for aqueous zinc‐based batteries owing to the large interlayer distance. Nevertheless, the low specific capacity of unmodified TMDs due to the high binding energy between host materials and carriers in electrolytes hinder their further development. Herein, a simple method to incorporate oxygen is reported to enhance the specific capacity of MoSe2. The in situ and ex situ characterization results confirm that the oxygen incorporated MoSe2 experiences proton‐dominated insertion electrochemistry during cycling. In addition, the theoretical calculation results demonstrate that the oxygen atoms with high electronegativity can effectively reduce the binding energy of adsorbing H+ and change charge distribution in the interlayer. As a result, incorporating oxygen significantly promotes H+ adsorption and diffusion, and thus greatly increases the specific capacity of MoSe2. This study provides an effective strategy to facilitate the kinetics of TMDs, and thus achieve high‐performance aqueous zinc‐based batteries. [ABSTRACT FROM AUTHOR]

Establishing local built‐in electric field of 2D semiconductors is one of the promising strategies to regulate the oriented charge delivery to active centers for enhancing photocatalytic performance. Herein, a novel heptamolybdate polyanions‐intercalated porous g‐C3N4 ([Mo7O24]6−‐pCN) catalyst with integrating highly desirable visible‐light photocatalytic features is reported. After intercalation, the apparent reaction rate constants (kapp) of [Mo7O24]6−‐pCN for bisphenol A (BPA) and 4‐chlorophenol (4‐CP) photodegradation are remarkably enhanced, which are 9.0 and 6.4 times faster than those of pCN, respectively. Analogously, the kapp values of [Mo7O24]6–‐CN for BPA and 4‐CP removal are also improved by contrast with CN. The experimental results and density functional theory calculations indicate that a local built‐in electric field is formed in [Mo7O24]6−‐pCN with a polarization direction from aromatic rings of g‐C3N4 to the inserted [Mo7O24]6− clusters. Driven by the electric field, photogenerated carriers can be efficiently separated for better reactive oxidative species (ROSs) production. These O atoms are also proved as adsorption sites for phenols, greatly reducing the migration distance of ROSs and thus improving photocatalytic performances. This work offers a reliable strategy to construct local built‐in electric field via polyoxometalates intercalation for effective solar energy conversion and phenolic wastewater remediation. [ABSTRACT FROM AUTHOR]

Ultrasound (US)‐mediated sonodynamic therapy (SDT) has the advantages of non‐invasiveness and deep tissue penetration. Nanosystems are prominently used in sonosensitization; however, most nano‐sonosensitizers have a low reactive oxygen species (ROS) yield, thus restraining the application of SDT. Sodium molybdenum bronze nanoparticles (SMB NPs) with rich oxygen vacancies are developed and interlayer gaps of molybdenum trioxide nanobelts are expanded. Owing to the increased oxygen vacancy density and wide interlayer gap‐induced narrower band gap of SMB NPs, the electrons (e–) and holes (h+) generated by US are separated more rapidly, and oxygen vacancies prevent electrons–holes recombination under US irradiation. SMB NPs exhibit a second near‐infrared (NIR‐II) photothermal effect to promote the generation of ROS by the sonosensitizer. The SMB NPs system is successfully realized to eliminate Staphylococcus aureus (S. aureus) and dissipate biofilm. Therefore, multimodal therapy using SMB NPs serves as an effective and promising regimen for deep‐seated bacterial infections. The newly developed Mo‐based sonosensitizer is presented for the first time to demonstrate excellent antimicrobial activity through hyperthermia‐promoting SDT therapeutics. This work proposes a novel strategy in the field of NIR‐II photo‐amplified SDT with Mo‐based materials for bacterial eradication and other important biomedical applications. [ABSTRACT FROM AUTHOR]

The technological barriers of the dimensional engineering and interfacial instability seriously hinder the scalable production of metallic (1T) transition metal dichalcogenides (TMD) monolayers. In this article, a facile and fast electron injection strategy is developed to modulate the d orbits of Mo center in trigonal prismatic 2H phases (MoS2 and MoSe2); meanwhile various cations (Li+, Na+, and K+) reinforce the in‐plane 1T‐atomic arrangement and expand the out‐of‐plane spacing for easy exfoliation. Theoretical and experimental evaluations further elucidate the decisive electron‐donating capability and suitable ionic radius in stabilizing 1T coordination. The as‐tailored 1T‐MoS2/MoSe2 anodes can achieve the robust Na+ storage in the half cells (5000 cycles at 5 A g–1) and extreme power output of 3134.9 W kg–1 in the full cell. This phase‐engineering approach enables the precise dimensional manipulation of the 1T TMDs, which further extends their application horizons as the cation host for the power‐oriented battery systems. [ABSTRACT FROM AUTHOR]

Solution‐processed transition metal oxides (TMOs) prepared from complex ion precursors are developed as promising scalable interfacial layers for non‐fullerene organic photovoltaics (OPVs); however, challenges remain in achieving defect‐free and highly oriented metal‐oxygen networks without post‐deposition treatments due to the presence of residual organic metal‐binding ligands in films. Herein, the novel strategy that the problematic organic metal‐binding ligands in TMO precursors can be successfully eliminated by an anion‐induced catalytic reaction (ACR) at room temperature is demonstrated, in which the low‐level anions induce electron redistribution and instability of TMO precursors, expediting binding ligand removal during the hydrolysis reaction. The subsequent condensation process facilitates a dimensionally confined and continuous metal‐oxygen network with a 20‐fold increase in electrical conductivity (from 8.4 × 10−4 to 1.8 × 10−2 S m−1) and superior work function tunability (from 5.1 to 5.3 eV) compared to the pristine film. The ACR‐derived TMO thin film on top of a ternary PBDB‐TF:Y6:PC71BM photoactive layer enables an inverted device configuration with improved efficiency of 17.6%, as well as enhanced stability over 70% of the initial efficiency for up to 100 h AM 1.5G illumination. [ABSTRACT FROM AUTHOR]

Although the hydrogenation of aromatics is important for the processing of fossil fuels and biofuels, it typically requires costly (e.g., noble metal‐based) catalysts and exhibits unsatisfactory selectivity. Herein, flake‐like nanocrystalline molybdenum carbide (α‐MoC) is surface‐engineered via Pd doping, and the synergy between the in‐situ generated Mo vacancies and doped Pd species is shown to promote the selective hydrogenation of naphthalene to decalin. Experimental and theoretical evidence reveal that this enhanced performance is due to the optimization of naphthalene adsorption energy and the establishment of a unique surface structure due to (i) surface environment modulation, (ii) the adjustment of electron density around Mo atoms, and (iii) the change in the strength of Mo‐H bonding caused by d‐band center optimization. Benefiting from the unique surface structure, the obtained optimum 0.5% Pd‐α‐MoC catalyst exhibits excellent performance. The developed strategy is successfully used to fabricate other noble metal (Pt, Ru)‐doped α‐MoC catalysts, thus holding promise as a universal method for the rational design of high‐performance metal carbide‐based hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Recently, a 2D metal boride – boridene – has been experimentally realized in the form of single‐layer molybdenum boride sheets with ordered metal vacancies, through selective etching of the nanolaminated 3D parent borides (Mo2/3Y1/3)2AlB2 and (Mo2/3Sc1/3)2AlB2. The chemical formula of the boridene was suggested to be Mo4/3B2‐xTz, where Tz denotes surface terminations. Here, the termination composition and material properties of Mo4/3B2‐xTz from both theoretical and experimental perspectives are investigated. Termination sites are considered theoretically for termination species T = O, OH, and F, and the energetically favored termination configuration is identified at z = 2 for both single species terminations and binary termination mixes of different stoichiometries in ordered and disordered configurations. Mo4/3B2‐xTz is shown to be dynamically stable for multiple termination stoichiometries, displaying semiconducting, semimetallic, or metallic behavior depending on how different terminations are combined. The approximate chemical formula of a freestanding film of boridene is attained as Mo1.33B1.9O0.3(OH)1.5F0.7 from X‐ray photoelectron spectroscopy (XPS) analysis which, within error margins, is consistent with the theoretical results. Finally, metallic and additive‐free Mo4/3B2‐xTz shows high catalytic performance for the hydrogen evolution reaction, with an onset potential of 0.15 V versus the reversible hydrogen electrode. [ABSTRACT FROM AUTHOR]

Sluggish water dissociation kinetics in the Volmer step on platinum‐free electrocatalysts limits the development of hydrogen evolution from economical water‐alkali electrolyser. Herein, an unusual nanosheets electrocatalyst of molybdenum‐doped cobalt selenide with selenium vacancy encapsulated within N‐doped carbon matrix (Mo‐Co0.85SeVSe/NC) for efficient hydrogen evolution reaction (HER) is reported. Benefiting from the optimized electronic structure, this Mo‐Co0.85SeVSe/NC nanosheet exhibits a high catalytic activity for alkaline HER, achieving the current densities of 10 and 200 mA cm−2 at low overpotentials of 151 and 275 mV, respectively. These results are among the highest catalytic activities in respect with all previously reported transition‐metal‐selenide based HER electrocatalysts. The combined in situ spectroscopic and theoretical studies reveal that the incorporation of Mo‐dopant and Se vacancies into Co0.85Se efficiently enhances electron transfer from Mo to Co atom through the bridging Se atom, leading to the formation of enriched electronic Co site to accelerate water dissociation, eventually facilitating the overall alkaline HER process. An integrated Zn‐H2O battery with a Mo‐Co0.85SeVSe/NC cathode is developed to further demonstrate the potential applications of the newly developed HER catalyst. [ABSTRACT FROM AUTHOR]

Eutectic gallium‐indium (EGaIn) liquid metal droplets have been considered as a suitable platform for producing customized 3D composites with functional nanomaterials owing to their soft and highly reductive surface. Herein, the synthesis of a 3D plasmonic oxide framework (POF) is reported by incorporating the ultra‐thin angstrom‐scale‐porous hexagonal molybdenum oxide (h‐MoO3) onto the spherical EGaIn nanodroplets through ultrasonication. Simultaneously, a large number of oxygen vacancies form in h‐MoO3, boosting its free charge carrier concentration and therefore generating a broad surface plasmon resonance across the whole visible light spectrum. The plasmonic chemical sensing properties of the POF is investigated by the surface‐enhanced Raman scattering detection of rhodamine 6G (R6G) at 532 nm, in which the minimum detectable concentration is 10−8m and the enhancement factor reached up to 6.14 × 106. The extended optical absorption of the POF also allowed the efficient degradation of the R6G dye under the excitation of ultraviolet‐filtered simulated solar light. Furthermore, the POF exhibits remarkable photocurrent responses towards the entire visible light region with the maximum response of ≈1588 A W−1 at 455 nm. This work demonstrates the great potential of the liquid metal‐based POFs for high‐performance sensing, catalytic, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Carbon laser‐patterning (CLaP) is emerging as a new tool for the precise and selective synthesis of functional carbon‐based materials for on‐chip applications. The aim of this work is to demonstrate the applicability of laser‐patterned nitrogen‐doped carbon (LP‐NC) for resistive gas‐sensing applications. Films of pre‐carbonized organic nanoparticles on polyethylenetherephthalate are carbonized with a CO2‐laser. Upon laser‐irradiation a compositional and morphological gradient in the films is generated with a carbon content of 92% near the top surface. The specific surface areas of the LP‐NC are increased by introducing sodium iodide (NaI) as a porogen. Electronic conductivity and surface area measurements corroborate the deeper penetration of the laser‐energy into the film in the presence of NaI. Furthermore, impregnation of LP‐NC with MoC1−x (<10 nm) nanoparticles is achieved by addition of ammonium heptamolybdate into the precursor film. The resulting doping‐sensitive nano‐grain boundaries between p‐type carbon and metallic MoC1−x lead to an improvement of the volatile organic compounds sensing response of ΔR/R0 = −3.7% or −0.8% for 1250 ppm acetone or 900 ppm toluene at room temperature, respectively, which is competitive with carbon‐based sensor materials. Further advances in sensitivity and in situ functionalization are expected to make CLaP a useful method for printing selective sensor arrays. [ABSTRACT FROM AUTHOR]

To couple hydrogen evolution reaction (HER) with urea oxidation reaction (UOR) is a promising approach to produce H2 with reduced energy consumption. However, the development of a low‐cost and high‐performance bifunctional electrocatalyst toward HER and UOR is still a challenge. In this work, oxygen‐incorporated nickel molybdenum phosphide nanotube arrays are synthesized on nickel foam (O‐NiMoP/NF) via electrodeposition accompanied with in‐situ template etching. Benefiting from the modulated electronic structure and the nanotube array architecture of O‐NiMoP, the self‐supporting O‐NiMoP/NF electrodes demonstrate highly efficient bifunctional catalytic activity toward HER and UOR. Particularly, in the HER and UOR (HER||UOR) coupled system for H2 production, a significantly reduced cell voltage of 1.55 V is obtained at the current density of 50 mA cm–2, which is about 300 mV lower than that of the conventional water electrolysis. Density functional theory calculations reveal that the remarkable HER and UOR activities originated from the Ni sites with the modulated electronic environment induced by Mo, P and O atoms, which facilitate the water dissociation during HER and balance the adsorption/desorption of the intermediates during UOR. The development of Ni‐based phosphides nanotube arrays as a bifunctional electrocatalyst in HER||OER system provides a new approach enabling energy‐saving H2 production. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) have attracted significant attention due to their intrinsic safety, cost‐effectiveness, and environmental friendliness. However, the common zinc metal anode suffers from zinc dendrite formation, self‐corrosion, and surface passivation, which impede the further application of aqueous ZIBs. Herein, carbon‐inserted molybdenum dioxide (MoO2) materials with laminated structure are designed as novel intercalation‐type anodes for ZIBs by combination of interlayer engineering and in situ carbonization of aniline guest in molybdenum trioxide interlayers. The uniform dispersion of carbon layers in laminated MoO2 not only provide fast transportation paths for electron but also strengthen the framework of MoO2, leading to high structural integration during high‐rate cycling. Benefiting from the unique structural design, the carbon‐inserted MoO2 electrode exhibits high initial Coulombic efficiency, excellent cycling stability, and outstanding rate capability. Multiple ex situ characterizations reveal its excellent electrochemical stability is derived from reversible intercalation mechanism and ultrastable structural framework. Furthermore, the rocking‐chair zinc‐ion full battery assembled with the zinc pre‐intercalated Na3V2(PO4)2O2F cathode presents excellent stability and ultralong lifespan with a high capacity retention of 91% over 8000 cycles. [ABSTRACT FROM AUTHOR]

Electron transfer between metal‐oxides and supports considerably affects the oxidative desulfurization (ODS) performance of catalysts, while this is far from being well understood. Herein, molybdenum dioxide with oxygen vacancies (VO‐MoO2) catalysts derived from Mo‐based metal‐organic frameworks are anchored on electron‐rich nitrogen‐doped carbon nanotubes (NC) to obtain excellent ODS activity and reusability. Results show that either dibenzothiophene (DBT) or 4,6‐dimethyldibenzothiophene (4,6‐DMDBT) is removed 100% on the composite catalyst (VO‐MoO2@NC) within 40 min of reaction when cumene hydroperoxide is chosen as an oxidant. After five cycles of reaction, DBT and 4,6‐DMDBT removal still exceeded 99.5 and 95.0%, respectively. Results from density functional theory calculations and characterizations confirm that the strong electron‐donating effect of NC on VO‐MoO2 can promote the dispersion of VO‐MoO2 and reduce the bond energy of the MoO bond, leading to exposure of active sites and enrichment of oxygen vacancies (VO). Furthermore, the strong interfacial electrostatic interaction caused by the electron transfer from NC to VO‐MoO2 can reduce the leaching of active sites of the catalyst. This study provides a versatile strategy of constructing strong electronic interaction between metal‐oxide and support via anchoring on NC for the design of high‐performance ODS catalysts. [ABSTRACT FROM AUTHOR]

The ever‐rising concerns with regards to energy shortages and climate change have made the search for clean and renewable energy sources a pressing priority for the sustainable development of societies. Although, conventional precious metal‐based catalysts such as platinum, iridium, and ruthenium are able to efficiently catalyze the conversion of chemical to electrical energy, they are often very costly, scarce, and suffer from poor stability, hence impeding their widespread applications. The limitations of the current state‐of art catalysts have propelled tremendous efforts in search for alternative catalysts. Notably, transition metal dichalcogenides (TMDs) have spurred much enthusiasm because of their natural abundance, low cost, and remarkable catalytic activity. Numerous studies have recounted that doping can tune the properties of TMDs and that vanadium dopants reportedly improve the electrical properties of Group 6 TMDs. Herein, the authors aspire to investigate the effects of doping varying amounts of vanadium on molybdenum dichalcogenides on their electrocatalytic activities toward hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction. Despite previous studies bespeaking promising effects, the results here demonstrate both improvements and worsening of electrocatalytic performances from varying the stoichiometry of vanadium dopants in molybdenum dichalcogenides, depending on the type of materials and intended electrochemical applications. [ABSTRACT FROM AUTHOR]

An ecofriendly and robust strategy is developed to construct a self‐supported monolithic electrode composed of N‐doped carbon hybridized with bimetallic molybdenum‐tungsten carbide (MoxW2−xC) to form composite nanowires for hydrogen evolution reaction (HER). The hybridization of MoxW2−xC with N‐doped carbon enables effective regulation of the electrocatalytic performance of the composite nanowires, endowing abundant accessible active sites derived from N‐doping and MoxW2−xC incorporation, outstanding conductivity resulting from the N‐doped carbon matrix, and appropriate positioning of the d‐band center with a thermodynamically favorable hydrogen adsorption free energy (ΔGH*) for efficient hydrogen evolution catalysis, which forms a binder‐free 3D self‐supported monolithic electrode with accessible nanopores, desirable chemical compositions and stable composite structure. By modulating the Mo/W ratio, the optimal Mo1.33W0.67C @ NC nanowires on carbon cloth achieve a low overpotential (at a geometric current density of 10 mA cm−2) of 115 and 108 mV and a small Tafel slope of 58.5 and 55.4 mV dec−1 in acidic and alkaline environments, respectively, which can maintain 40 h of stable performance, outperforming most of the reported metal‐carbide‐based HER electrocatalysts. [ABSTRACT FROM AUTHOR]

The necessity for better water splitting requires speedy development of efficient catalysts with high activity, long‐term stability, and cost effectiveness. In this work, a bifunctional catalyst originating from the interfacial assembly of a thin Mo,P‐codoped Co layer (≈50 nm) shelled Co nanowire (Co‐Mo‐P/CoNWs) network is fabricated via a facile approach. The catalyst exhibits low overpotentials of 0.08 and 0.27 V to reach a current response of 20 mA cm−2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively, together with long‐term stability in 1.0 m KOH medium. The outstanding performance is further demonstrated by a Co‐Mo‐P/CoNWs‐based electrolyzer, which enables a cell voltage of only 1.495 V to reach 10 mA cm−2, superior to one derived from commercial (Pt/C + RuO2/C) as well as to various reports recently published elsewhere. It is recognized that the formation of multiactive centers together with the increased active site number caused by Mo and P dual doping synergistically promote both hydrogen and oxygen evolution performance. Such a hybrid material opens a new approach for developing efficient and cost‐effective catalysts for water splitting application. [ABSTRACT FROM AUTHOR]

Orthorhombic molybdenum trioxide (MoO3) is one of the most promising anode materials for sodium‐ion batteries because of its rich chemistry associated with multiple valence states and intriguing layered structure. However, MoO3 still suffers from the low rate capability and poor cycle induced by pulverization during de/sodiation. An ingenious two‐step synthesis strategy to fine tune the layer structure of MoO3 targeting stable and fast sodium ionic diffusion channels is reported here. By integrating partially reduction and organic molecule intercalation methodologies, the interlayer spacing of MoO3 is remarkably enlarged to 10.40 Å and the layer structural integration are reinforced by dimercapto groups of bismuththiol molecules. Comprehensive characterizations and density functional theory calculations prove that the intercalated bismuththiol (DMcT) molecules substantially enhanced electronic conductivity and effectively shield the electrostatic interaction between Na+ and the MoO3 host by conjugated double bond, resulting in improved Na+ insertion/extraction kinetics. Benefiting from these features, the newly devised layered MoO3 electrode achieves excellent long‐term cycling stability and outstanding rate performance. These achievements are of vital significance for the preparation of sodium‐ion battery anode materials with high‐rate capability and long cycling life using intercalation chemistry. [ABSTRACT FROM AUTHOR]

The emergence of nanomaterials in the past decades has greatly advanced modern energy storage devices. Nanomaterials can offer high capacity and fast kinetics yet are prone to rapid morphological evolution and degradation. As a result, they are often hybridized with a stable framework in order to gain stability and fully utilize its advantages. However, candidates for such framework materials are rather limited, with carbon, conductive polymers, and Ti‐based oxides being the only choices; note these are all inactive or intercalation compounds. Conventionally, alloying‐/conversion‐type electrodes, which are thought to be electrochemically unstable by themselves, have never been considered as framework materials. This concept is challenged. Successful application of conversion‐type MnO nanorod as a anode framework for high‐capacity Mo2C/MoOx nanoparticles has been demonstrated in sodium‐ion batteries. Surprisingly, it can stably deliver 110 mAh g−1 under extremely high rate of 8000 mA g−1 (≈70 C) over 40 000 cycles with no capacity decay. More generally, this is considered as a proof of concept and much more alloying‐/conversion‐type materials are expected to be explored for such applications. [ABSTRACT FROM AUTHOR]

Abstract: Telluride molybdenum (MoTe2) nanosheets with wide near‐infrared (NIR) absorbance are functionalized with polyethylene glycol‐cyclic arginine‐glycine‐aspartic acid tripeptide (PEG‐cRGD). After loading a chemotherapeutic drug (doxorubicin, DOX), MoTe2‐PEG‐cRGD/DOX is used for combined photothermal therapy and chemotherapy. With the high photothermal conversion efficiency, MoTe2‐PEG‐cRGD/DOX exhibits favorable cells killing ability under NIR irradiation. Owing to the cRGD‐mediated specific tumor targeting, MoTe2‐PEG‐cRGD/DOX shows efficient accumulation in tumors to induce a strong tumor ablation effect. MoTe2‐PEG‐cRGD nanosheets, which are relatively stable in the circulation, could be degraded under NIR ray. The in vitro and in vivo experimental results demonstrate that this theranostic nanoagent, which could accumulate in tumors to allow photothermal imaging and combined therapy, is readily degradable in normal organs to enable rapid excretion and avoid long‐term retention/toxicity, holding great potential to treat tumor effectively. [ABSTRACT FROM AUTHOR]

Abstract: Highly efficient platinum‐alternative bifunctional catalysts by using abundant non‐noble metal species are of critical importance to the future sustainable energy reserves. Unfortunately, current electrocatalysts toward hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) are far from satisfactory because of lacking reasonable design and assembly protocols. A type of 1‐nm molybdenum carbide nanoparticles confined in mesh‐like nitrogen‐doped carbon (Mo2C@NC nanomesh) with high specific surface area is reported here. In addition to the superior ORR performance comparable to platinum, the catalyst offers a high HER activity with small Tafel slope of 33.7 mV dec−1 and low overpotential of 36 mV to reach −10 mA cm−2. Theoretical calculations indicate that the active sites of the catalyst are mainly located at Mo atoms adjacent to the N‐doped carbon layer, which contributes the high HER activity. These findings show the great potential of Mo2C species in wide electrocatalysis applications. [ABSTRACT FROM AUTHOR]

Abstract: MXenes, a young family of 2D transition metal carbides/nitrides, show great potential in electrochemical energy storage applications. Herein, a high performance ultrathin flexible solid‐state supercapacitor is demonstrated based on a Mo1.33C MXene with vacancy ordering in an aligned layer structure MXene/poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) composite film posttreated with concentrated H2SO4. The flexible solid‐state supercapacitor delivers a maximum capacitance of 568 F cm−3, an ultrahigh energy density of 33.2 mWh cm−3 and a power density of 19 470 mW cm−3. The Mo1.33C MXene/PEDOT:PSS composite film shows a reduction in resistance upon H2SO4 treatment, a higher capacitance (1310 F cm−3) and improved rate capabilities than both pristine Mo1.33C MXene and the nontreated Mo1.33C/PEDOT:PSS composite films. The enhanced capacitance and stability are attributed to the synergistic effect of increased interlayer spacing between Mo1.33C MXene layers due to insertion of conductive PEDOT, and surface redox processes of the PEDOT and the MXene. [ABSTRACT FROM AUTHOR]

A table of content for the April 19, 2016 issue of the periodical "Advanced Functional Materials" is presented.

In this paper, a technique using mixed transition-metal oxides as contact interlayers to modulate both the electron- and hole-injections in ambipolar organic field-effect transistors (OFETs) is presented. The cesium carbonate (Cs2CO3) and vanadium pentoixide (V2O5) are found to greatly and independently improve the charge injection properties for electrons and holes in the ambipolar OFETs using organic semiconductor of diketopyrrolopyrrolethieno[3,2-b]thiophene copolymer (DPPT-TT) and contact electrodes of molybdenum (Mo). When Cs2CO3 and V2O5 are blended at various mixing ratios, they are observed to very finely and constantly regulate the Mo's work function from −4.2 eV to −4.8 eV, leading to high electron- and hole-mobilities as high as 2.6 and 2.98 cm2 V−1 s−1, respectively. The most remarkable finding is that the device characteristics and device performance can be gradually controlled by adjusting the composition of mixed-oxide interlayers, which is highly desired for such applications as complementary circuitry that requires well matched n-channel and p-channel device operations. Therefore, such simple interface engineering in conjunction with utilization of ambipolar semiconductors can truly enable the promising low-cost and soft organic electronics for extensive applications. [ABSTRACT FROM AUTHOR]

Poly(3-hexylthiophene) (P3HT) is p-doped by the new soluble dopant molybdenum tris[1-(methoxycarbonyl)-2-(trifluoromethyl)-ethane-1,2-dithiolene] and investigated via photoemission spectroscopy and transport measurements. Soft-contact transfer lamination of thin layers of the doped P3HT on undoped polymer layers is used to create spatially-confined doped regions, which serve as hole-injection contacts on P3HT diodes. This strategy is then used to create efficient hole-collecting contacts on solution-processed inverted polymer solar cells. [ABSTRACT FROM AUTHOR]

Luminescent hybrid copolymers are obtained by copolymerizing in bulk methylmethacrylate with a methacrylic acid (MAC) solution containing [ n-Bu4N]2[Mo6Br8(MAC)6], and aliquots of an Er(TMHD)3 complex (TMHD for 2,2,6,6-tetramethyl-3,5-heptanedione) solution. This leads to novel homogeneous and transparent hybrid materials in which the Er3+ infrared luminescence at 1.55 μm, a standard wavelength for telecommunication applications, is up to six time more intense in the presence of Mo6 clusters when samples are irradiated at 476.5 nm. This work demonstrates the outstanding potential of Mo6 clusters, compounds obtained by high-temperature solid-state synthesis, in the design of functional hybrid materials via soft chemistry routes. [ABSTRACT FROM AUTHOR]

Reactive dissolution and its effects on electrical conduction, morphological change and chemical transformation in thin films of Mg, AZ31B Mg alloy, Zn, Fe, W, and Mo in de-ionized (DI) water and simulated body fluids (Hanks' solution pH 5-8) are systematically studied, to assess the potential for use of these metals in water-soluble, that is, physically "transient", electronics. The results indicate that the electrical dissolution rates in thin films can be much different that traditionally reported corrosion rates in corresponding bulk materials. Silicon metal oxide field effect transistors (MOSFETs) built with these metals demonstrate feasibility for use in transient electronics. [ABSTRACT FROM AUTHOR]

The article presents abstracts related to functional materials, that include two-dimensional semiconductors molybdenum trioxide and dichalcogenides, polarization switching dynamics in ferroelectric capacitors, and nematic liquid crystals present inside cubic microlattices.

In the quest to discover the properties of planar semiconductors, two-dimensional molybdenum trioxide and dichalcogenides have recently attracted a large amount of interest. This family, which includes molybdenum trioxide (MoO3), disulphide (MoS2), diselenide (MoSe2) and ditelluride (MoTe2), possesses many unique properties that make its compounds appealing for a wide range of applications. These properties can be thickness dependent and may be manipulated via a large number of physical and chemical processes. In this Feature Article, a comprehensive review is delivered of the fundamental properties, synthesis techniques and applications of layered and planar MoO3, MoS2, MoSe2, and MoTe2 along with their future prospects. [ABSTRACT FROM AUTHOR]

Molybdenum Carbide Electrocatalysts: Synergistically Tuning Electronic Structure of Porous -Mo2C Spheres by Co Doping and Mo-Vacancies Defect Engineering for Optimizing Hydrogen Evolution Reaction Activity (Adv. Funct. Keywords: Co doping; hydrogen evolution reaction; Mo vacancies; molybdenum carbide electrocatalysts; electronic structures EN Co doping hydrogen evolution reaction Mo vacancies molybdenum carbide electrocatalysts electronic structures 1 1 1 05/13/20 20200511 NES 200511 In article number 2000561, Tiejun Wang and co-workers show that cobalt-doping and Mo vacancies on the molybdenum carbide ( -Mo SB 2 sb C) surface synergistically tune the electron density and d-band center, which effectively enhance the hydrogen evolution reaction (HER) performance over the sphere-type porous -Mo SB 2 sb C-based catalysts. Co doping, hydrogen evolution reaction, Mo vacancies, molybdenum carbide electrocatalysts, electronic structures. [Extracted from the article]

Two‐dimensional (2D) van der Waals materials with in‐plane anisotropy are of great interest for directional transport of charge and energy, as exemplified by recent studies on black phosphorus and α‐phase molybdenum trioxide (α‐MO3). Here, a layered van der Waals semiconductor with in‐plane anisotropy built upon the superatomic units of Mo6S3Br6 is reported. This material possesses robust 2D characteristics with a direct gap of 1.64 eV, as determined by scanning tunneling spectroscopy and first‐principles calculations. Polarization‐dependent Raman spectroscopy measurement and density functional theory calculation reveal strong in‐plane anisotropy. These results suggest an effective strategy to explore anisotropic 2D electronic and optoelectronic properties from superatomic building blocks with multifunctionality, emergent properties, and hierarchical control. [ABSTRACT FROM AUTHOR]