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Results for “nitridation”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Selective CO2 Reduction Catalyzed by Single Cobalt Sites on Carbon Nitride under Visible-Light Irradiation
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Unveiling the Pockels coefficient of ferroelectric nitride ScAlN
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Moiré band structure engineering using a twisted boron nitride substrate
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Tunable crystal symmetry in graphene–boron nitride heterostructures with coexisting moiré superlattices
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Wafer-scale single-crystal hexagonal boron nitride monolayers on Cu (111)
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Intrinsic toughening and stable crack propagation in hexagonal boron nitride
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Effect of Auger recombination on transient optical properties in XUV and soft X-ray irradiated silicon nitride
Spatially encoded measurements of transient optical transmissivity became a standard tool for temporal diagnostics of free-electron-laser (FEL) pulses, as well as for the arrival time measurements in X-ray pump and optical probe experiments. The modern experimental techniques can measure changes in optical coefficients with a temporal resolution better than 10 fs. This, in an ideal case, would imply a similar resolution for the temporal pulse properties and the arrival time jitter between the FEL and optical laser pulses. However, carrier transport within the material and out of its surface, as well as carrier recombination may, in addition, significantly decrease the number of carriers. This would strongly affect the transient optical properties, making the diagnostic measurement inaccurate. Below we analyze in detail the effects of those processes on the optical properties of XUV and soft X-ray irradiated Si 3 N 4 , on sub-picosecond timescales. Si 3 N 4 is a wide-gap insulating material widely used for FEL pulse diagnostics. Theoretical predictions are compared with the published results of two experiments at FERMI and LCLS facilities, and with our own recent measurement. The comparison indicates that three body Auger recombination strongly affects the optical response of Si 3 N 4 after its collisional ionization stops. By deconvolving the contribution of Auger recombination, in future applications one could regain a high temporal resolution for the reconstruction of the FEL pulse properties measured with a Si 3 N 4 -based diagnostics tool.
Interfacial charge transfer enhancement via formation of binary molecular assemblies on electronically corrugated boron nitride
Using scanning tunneling microscopy/spectroscopy (STM/STS) in conjunction with finite element simulation, we investigate the interfacial behaviors in single-component zinc phthalocyanine (ZnPc) and hexadecafluorinated zinc phthalocyanine (F 16 ZnPc) molecular overlayers as well as their 1 : 1 mixedphase superstructures on h-BN/Cu(111). We show herein that the formation of the binary molecular superstructure drastically increases the charge transfer between F 16 ZnPc molecules and the substrate, which is attributed to the greater electrostatic stability of the binary assembly compared to that of the pure phase. This study highlights the significant complication in the design of donor–acceptor molecular thin films as the presence of the substrate, even a weakly interacting one, such as h-BN/metal, can still perturb the intermolecular charge transfer and thereby the physical behaviors of the hybrid system via interfacial processes.
Syngas molecules as probes for defects in 2D hexagonal boron nitride: their adsorption and vibrations
Through insights from first-principles calculations, we predict defect-laden h -BN, particularly with N vacancy, to have good propensity toward CO and CO 2 hydrogenation. Vibrational frequencies of CO and CO 2 are proposed as identifiers of defect type.
Synthesis and chemical stability of technetium nitrides
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Anharmonic lattice dynamics of superionic lithium nitride
We explore the crystal vibrations of Li 3 N and their connection to the high-temperature superionic transition.
Magnetism and interlayer bonding in pores of Bernal-stacked hexagonal boron nitride
When single-layer h-BN is subjected to a high-energy electron beam, triangular pores with nitrogen edges are formed. Because of the broken sp 2 bonds, these pores are known to possess magnetic states. Here, we report on the magnetism and electronic structure of triangular pores as a function of their size. Moreover, in the Bernal-stacked h-BN (AB-h-BN), multilayer pores with parallel edges can be created, which is not possible in the commonly fabricated multilayer AA'-h-BN. Given that these pores can be manufactured in a well-controlled fashion using an electron beam, it is important to understand the interactions of pores in neighboring layers. We find that in certain configurations, the edges of the neighboring pores remain open and retain their magnetism, and in others, they form interlayer bonds. We present a comprehensive report on these configurations for small nanopores. We find that at low temperatures, these pores have near degenerate magnetic configurations, and may be utilized in magnetoresistance and spintronics applications. In the process of forming larger multilayer nanopores, interlayer bonds can form, reducing the magnetization. Yet, unbonded parallel multilayer edges remain available at all sizes. Understanding these pores is also helpful in a multitude of applications such as DNA sequencing and quantum emission.
Novel boron nitride MXenes as promising energy storage materials
MXenes are promising materials for rechargeable metal ion batteries and supercapacitors due to their high energy storage capacities, high electrical and ionic conductivities, and ease of synthesis.
Electrochemically engineered domain: nickel–hydroxide/nickel nitride composite for alkaline HER electrocatalysis
The impact ofin situelectrooxidation in a Ni 3 N electrocatalyst on its hydrogen evolution activity and electrochemical stability was investigated in alkaline media.
Chemical vapor deposition of hexagonal boron nitride on germanium from borazine
hBN is deposited onto semiconducting substrates with control over the domain alignment (including close-to-unidirectional alignment) and monolayer quality.