- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Symmetry and Topology Code of Cluster Crystal Structure Self-Assembly for Metal Oxides: Cs11O3-mP56, Rb(Cs11O3)-oP30, Cs(Cs11O3)-oP60, Rb3(Rb4)(Cs11O3)-oP84, (Cs4)(Cs6)(Cs11O3)-hP24, Rb9O2-mP22, (Rb3)(Rb9O2)-hP28, and (Rb2O)3(Rb13)-cF176
摘要： Geometric and topologic analysis was carried out for metal oxides Cs11O3-mP56, Rb(Cs11O3)-oP30, Cs(Cs11O3)-oP60, Rb3(Rb4)(Cs11O3)-oP84, (Cs4)(Cs6)(Cs11O3)-hP24, Rb9O2-mP22, (Rb3)(Rb9O2)-hP28, and (Rb2O)3(Rb13)-cF176, which are formed from oxygen-containing metal melts. Special algorithms of partitioning structural graphs into cluster structures (the TOPOS program package) were used to identify the precursor clusters of crystal structures. The precursor clusters participating in crystal structure self-assembly were identified to be three-octahedral Cs11O3, two-octahedral Rb9O2, octahedral Cs6, tetrahedral Cs4 and Rb4, and icosahedral Rb13. The symmetry and topology code of crystal structure self-assembly from precursor clusters was reconstituted as: primary chain → microlayer → microframework. The Cs11O3 and Rb9O2 crystal structures were found to be self-assembled from three-octahedral clusters Cs11O3 and two-octahedral clusters Rb9O2, respectively. The Rb(Cs11O3) and Cs(Cs11O3) framework structures are assembled from clusters Cs11O3 and accommodate Rb and Cs atoms in their voids. The Rb3(Rb4)(Cs11O3) framework structure is assembled from clusters Cs11O3 and Rb4 and accommodates Rb atoms in its voids. The (Cs6)(Cs4)(Cs11O3) framework structure is self-assembled from clusters Cs11O3, Cs6, and Cs4. The Rb3(Rb9O2)-hP28 framework structure is assembled from clusters Rb9O2 and atoms Rb; the (Rb2O)3(Rb13) framework structure is assembled from icosahedra Rb13 and clusters Rb2O.
关键词： octahedral,and icosahedral precursor clusters,crystal structure self-assembly,and Rb metal oxides,Cs,tetrahedral,Rb-,Cs-
更新于2025-09-19 17:15:36
-
[IEEE 2018 IEEE SENSORS - New Delhi, India (2018.10.28-2018.10.31)] 2018 IEEE SENSORS - Single-Crystalline Metal Oxide, Resistive Gas Sensors Advances and Perspectives
摘要： Here we review recent results on the synthesis of single-crystalline metal oxide nanomaterials and their integration in resistive gas sensing devices. Emphasis is put on the integration of such nanomaterials in a wide spectrum of transducing platforms, ranging from standard ceramic to silicon MEMS or flexible polymeric. Some strategies for achieving higher selectivity are discussed, which are followed by a discussion on the development of advanced operation techniques for achieving more stable and faster response to gases. Finally, some aspects that remain open for research are identified.
关键词： surface potential control,nanowires,nanoparticles,chemoresistors,metal oxides,UV light excitation
更新于2025-09-19 17:15:36
-
Eighteen functional monolayer metal oxides: wide bandgap semiconductors with superior oxidation resistance and ultrahigh carrier mobility
摘要： Layered metal oxides have emerged as an up-and-comer in the family of two-dimensional materials due to their natural abundance, intrinsic bandgap, and chemical inertness. Based on first-principles calculations, we systematically investigated the atomic structures, energetic stability, and electronic properties of 18 monolayer metal oxides. All these monolayer metal oxides are predicted to be energetically favorable with negative formation energies in the range of -4.27 to -0.47 eV per atom, suggesting good experimental feasibility for synthesis of these monolayer metal oxides. Monolayer metal oxides exhibit superior oxidation resistance, and possess modest to wide bandgaps (1.22–6.48 eV) and high carrier mobility (especially up to 8540 cm2 V?1 s?1 for the InO monolayer), thereby rendering these low-dimensional materials promising candidates for carrier transport. Also, a pronounced in-plane anisotropy for the carrier mobility with a longitudinal/horizontal ratio as large as 115 is revealed for the monolayer metal oxides. These 2D metal oxides exhibit notable absorption in the ultraviolet range with the absorption coefficient >10? cm?1. The combined novel properties of these monolayer metal oxides offer a wide range of opportunities for advanced electronic and optoelectronic applications.
关键词： two-dimensional materials,optoelectronics,monolayer metal oxides,bandgap,carrier mobility,oxidation resistance
更新于2025-09-19 17:15:36
-
Ultrafast Laser Manufacture of Stable, Efficient Ultrafine Noble Metal Catalysts Mediated with MOF Derived High Density Defective Metal Oxides
摘要： Supported metal nanoparticles (MNPs) undergo severe aggregation, especially when the interaction between MNPs and their supports are limited and weak where their performance deteriorates dramatically. This becomes more severe when catalysts are operated under high temperature. Here, it is reported that MNPs including Pt, Au, Rh, and Ru, with sub-2 nm size can be stabilized on densely packed defective CeO2 nanoparticles with sub-5 nm size via strong coupling by direct laser conversion of corresponding metal ions encapsulated cerous metal–organic frameworks (Ce-MOFs). Ce-MOF serves as an ideal dispersion precursor to uniformly encapsulate noble metal ions in their orderly arranged pores. Ultrafast laser vaporization and cooling forms uniform, ultra-small, well-mixed, and exceptionally dense nanoparticles of metal and metal oxide concurrently. The laser-induced ultrafast reaction (within tens of nanoseconds) facilitates the precipitation of CeO2 nanoparticles with abundant surficial defects. Due to the well-mixed ultrasmall Pt and CeO2 components with strong coupling, this catalyst exhibits exceptionally high stability and activity both at low and high temperatures (170–1100 °C) for CO oxidation in long-term operation, significantly exceeding catalysts prepared by traditional methods. The scalable feature of laser and huge MOF family make it a versatile method for the production of MNP-based nanocomposites in wide applications.
关键词： noble metal catalysts,lasers,metal oxides,defects,metal–organic frameworks
更新于2025-09-19 17:13:59
-
Functional TiO2 interlayer for all-transparent metal-oxide photovoltaics
摘要： Metal oxide has a high energy bandgap and passes the visible light to enlighten the vision to human eyes. However, the strong and harmful UV light is easily captured by large bandgap metal oxide materials. One of the promising applications of metal oxide manipulation would be the transparent solar cells for the transparent window, to guarantee the view of visible light and generate electric power from the invisible UV radiation. Herein, we demonstrate the all-transparent photovoltaics for see-through applications with the functional deployment of TiO2 layer. P-type NiO and n-type ZnO form a heterojunction to establish a photovoltage. TiO2 layer with donor concentration >1019 cm-3 has flat-band potential of 0.4 V vs reversible hydrogen electrode (RHE) and is significantly higher than that of the photoactive ZnO layer, TiO2 layer insertion enables the multifunctions of giving a back surface field and also serving as a carrier selective transport layer. The ultrathin TiO2 embedded ZnO/NiO device has Ag nanowire top electrode and is highly transparent (>50%) in the visible range. This transparent solar cell provides power conversion efficiency of 6.1% and incident photon to charge carrier efficiency of 79.5% under UV light illumination. Mott-Schottky analysis showed the flat band potential to be 0.9 V by using the TiO2 layer insertion to induce the significant higher photovoltage and photocurrent on/off ratio of higher than 5×105 and played a vital role in the enhanced performance of ZnO/NiO heterostructure. We demonstrated the enhancement of the minority carrier lifetime for a broadband of light illumination via back surface field formation and proposed the energy band-diagram. We may suggest that this high transparent photovoltaic device can be functionally applied on-demands of power generation windows of electronic devices, vehicles and building.
关键词： back surface field,interface engineering,all-metal oxides,Transparent photovoltaics,transient spectroscopy
更新于2025-09-19 17:13:59
-
Laser induced ultrafast combustion synthesis of solution-based AlO <sub/>x</sub> for thin film transistors
摘要： Solution processing of amorphous metal oxides using excimer laser annealing (ELA) has been lately used as a viable option to implement large-area electronics, offering high quality materials at a reduced associated cost and process time. However, the research has been focused on semiconductor and transparent conductive oxide layers rather than on the insulator layer. In this work we present amorphous aluminum oxide (AlOx) thin films produced at low temperature (≤150 °C) via combustion synthesis triggered by ELA, for oxide thin film transistors (TFTs) suitable for manufacturing flexible electronics. The study showed that combining ELA and combustion synthesis leads to an improvement in the dielectric thin film’s densification in a shorter time (≤15 min). Optimized dielectric layers were obtained combining a short drying cycle at 150 °C followed by ELA treatment. High breakdown voltage (4 MV cm?1) and optimal dielectric constant (9) was attained. In general, TFT devices comprising the AlOx fabricated with a drying cycle of 15 min followed by ELA presented great TFT properties, a high saturation mobility (20.4 ± 0.9 cm2 V?1 s?1), a small subthreshold slope (0.10 ± 0.01 V dec?1) and a turn-on voltage ≈0 V. ELA is shown to provide excellent quality solution-based high-k AlOx dielectric, that surpass other methods, like hot plate annealing and deep ultraviolet (DUV) curing. The results achieved are promising and expected to be of high value to the printed electronic industry due to the ultra-fast film densification and the surface/area selective nature of ELA.
关键词： thin film transistors,excimer laser annealing,solution processing,amorphous metal oxides,combustion synthesis,flexible electronics
更新于2025-09-19 17:13:59
-
Impact of the Plasmonic Metal Oxide-Induced Photocatalytic Processes on the Interaction of Quantum Dots with Metallic Nanoparticles
摘要： We study plasmonic control of photocatalytic properties of metal oxides and the ways they influence interaction of quantum dots with metallic nanostructures. For this, gold nanostructures are coated with ultrathin layers of metal oxides (Al, Cu, Cr, or Ti oxide) and then covered with CdSe/ZnS quantum dots. The results show how the photocatalytic properties of such metal oxides are renormalized by plasmon near fields. In the cases of Al, Cr, and Ti oxides, the results mostly indicate the direct impact of plasmon fields via enhancement of optical excitations of the quantum dots. For the case of Cu oxide, however, the outcomes are found to be quite unique. In the absence of the plasmonic structures, such an oxide (CuO) presents highly active photocatalytic processes, leading to complete annihilation of the quantum dot emission. In the presence of the metallic nanostructures, the emission of such quantum dots is revived, offering an ultrafast decay process (～112 ps). These results indicate that in the case of CuO, the plasmonic metal oxide-induced photocatalytic processes include not only direct impact of plasmon near fields on the optical excitations of quantum dots but also the enhancement of interband transitions in CuO nanoparticles. The effects of energy transfer from quantum dots to metallic nanostructures and its equalization with Purcell effects on such processes are discussed.
关键词： ultrafast decay process,photocatalytic properties,plasmonic control,metallic nanostructures,Purcell effects,plasmon near fields,energy transfer,quantum dots,metal oxides
更新于2025-09-19 17:13:59
-
Effect of nanostructured metal oxides (CdO, Al2O3, Cu2O) embedded in PVA via Nd:YAG pulsed laser ablation on their optical and structural properties
摘要： The physiochemical properties of Polyvinyl Alcohol (PVA) film was enhanced by embedding with nanostructured metal oxides (CdO, Al2O3, and Cu2O) via one-pot and green method, nanosecond Nd:YAG pulsed laser ablation in liquids technique (PLAL). This process was carried by ablation of metal targets (cadmium, copper, and aluminum) immersed in PVA solution by high intensity pulsed laser in the focusing condition. The enhancing of the PVA properties were appeared by studying the structure, optical and morphology of the prepared films before and after embedding by several technique as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV–Visible, Photoluminescence (PL), Scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX). From structural investigation, the XRD patterns showed a reduction of CdO, Al2O3, and Cu2O nanoparticles within PVA chain. From optical investigation, the interaction and the structural modifications occurred between PVA chains and each metal oxide nanoparticles appeared in stretching vibration bands, the optical energy band gap (Eg) values by using Tauc equation equaled to 2.33, 3.63, and 3.54 eV for the oxide of Cd, Al, and Cu, respectively, are a good agreement with previous work, and the Photoluminescence spectra showed decreasing in emission intensity in the case of embedding with metal oxides. From morphological investigation, the FE-SEM images showed a homogeneous distribution with spherical shape of metal oxides through the polymer of PVA. The qualitative and semi-quantitative elemental analysis of the prepared samples via EDX technique confirmed the embedding of the metal oxide in the PVA structure. This work helps to open the route to produce various properties of PVA by embedded with different nanostructured metal oxides.
关键词： Laser ablation,Al2O3,Nd:YAG,Metal oxides,nanosecond,PVA,Nanomaterials,CdO,Cu2O
更新于2025-09-16 10:30:52
-
Ultrafast fabrication of Cu oxide micro/nano-structures via laser ablation to promote oxygen evolution reaction
摘要： Despite the tremendous efforts on the preparation of efficient oxygen evolution reaction (OER) electrocatalysts, it is still a challenge to fabricate stable OER electrocatalysts with good performance on a large scale in a simple, fast, green, and environment-friendly way. Herein, we report a simple way via femtosecond laser ablation to fabricate Cu oxide micro/nano-structures on Cu foams by fine-tuning of the laser parameters. The present method is ultrafast, non-contact, high efficiency, easy control, sustainable, and environment-friendly. The fabricated catalysts exhibit remarkable OER activity and excellent durability in 1 M KOH.
关键词： Water splitting,Laser ablation,Metal oxides,Oxygen evolution reaction
更新于2025-09-16 10:30:52
-
Interfacial engineering to boost photoresponse performance and stability of V2O5/n-Si heterojunction photodetectors
摘要： Transitional metal oxides (TMOs) have demonstrated as a promising alternative to doped layers in high-efficient crystalline silicon heterojunction solar cells. However, the unintentional oxidation causes serious carrier recombination at the interface, which accounts for the low photoelectric conversion efficiency and poor stability. Herein, a self-powered, broad-band, fast-response V2O5/n-Si heterojunction photodetectors (PDs) are fabricated by thermal evaporation of an ultrathin V2O5 thin films on nanoporous pyramid silicon structures. By interfacial engineering with structural optimization and surface methyl passivation, the photodetection performance and stability of V2O5/n-Si PDs can be significantly enhanced. The V2O5/n-Si heterojunction PDs demonstrate a high on/off ratio of 1.4×104, fast-response speed of 9.5 μs, high responsivity of 185 mA·W-1 (@940 nm) and high specific detectivity (1.34×1012 Jones). Based on the energy band alignment analysis, the excellent photoresponse performance is mainly attributed to the efficient carrier separation after surface passivation by methyl group. Additionally, the built-in electric field at the interface also accelerates the charge carrier separation. Our work would contribute to the fabrications of other TMOs-based heterojunctions, and give some enlightening insights into the understanding of carrier transportation in heterojunctions.
关键词： Carrier selective contact,Heterojunction photodetectors,Transition metal oxides,Interface engineering
更新于2025-09-16 10:30:52