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Titanium nitride and vanadium nitride–carbon-based composite systems, TiN/C and VN/C, were prepared using a new synthesis method based on the thermal decomposition of titanyl tetraphenyl porphyrin (TiOTPP) and vanadyl tetraphenyl porphyrin (VOTPP), respectively. The structure of the TiN/C and VN/C composite materials, as well as their precursors, were characterized using Fourier Transformed Infrared Spectroscopy, X-Ray diffraction (XRD), X-Ray energy dispersive (EDS) and X-Ray photoelectron spectroscopy (XPS). Morphologies of the TiN/C and VN/C composites were examined by means of scanning electron (SEM) and transmission electron (TEM) microscopy. The synthesis of the non-metalated tetraphenyl porphyrin, the titanium, and vanadium tetraphenyl porphyrin complexes were confirmed using FTIR. The thermal decomposition of the titanium and vanadium tetraphenyl porphyrin complexes produced the respective metal nitride encapsulated in a carbon matrix; this was confirmed by XRD, SEM, TEM, and XPS. From the XRD patterns, it was determined that the TiN and VN were presented in cubic form with expected space group FM-3M and 1:1 (metal:N) stoichiometry. The XPS results confirmed the presence of both TiN and VN in the carbon matrix without metal carbides. The SEM and TEM results showed that both TiN and VN nanoparticles formed small clusters throughout the carbon matrix; the EDS results revealed a uniform composition. The synthesis method presented in this work is novel and serves as an effective means to produce TiN and VN NPs with good structure and morphology embedded in a carbon matrix.
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Atomic Layer Deposition of Nickel Using Ni(dmamb)2 and ZnO Adhesion Layer Without Plasma
Abstract In this study, a novel deposition technique that utilizes diethylzinc (C4H10ZnO) with H2O to form a ZnO adhesion layer was proposed. This technique was followed by the deposition of vaporized nickel(II) 1-dimethylamino-2-methyl-2-butoxide (Ni(dmamb)2) and H2gas to facilitate the deposit of uniform layers of nickel on the ZnO adhesion layer using atomic layer deposition. Deposition temperatures ranged from 220 to 300 °C. Thickness, composition, and crystallographic structure results were analyzed using spectroscopic ellipsometry, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD), respectively. An average growth rate of approximately 0.0105 angstroms per cycle at 260 °C was observed via ellipsometry. Uniform deposition of ZnO with less than 1% of Ni was displayed by utilizing the elemental analysis function via SEM, thereby providing high-quality images. XPS revealed ionizations consistent with nickel and ZnO through the kinetic and binding energies of each detected electron. XRD provided supplemental information regarding the validity of ZnO by exhibiting crystalline attributes, revealing the presence of its hexagonal wurtzite structure.
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- Award ID(s):
- 1914751
- PAR ID:
- 10543192
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Nanomanufacturing and Metrology
- Volume:
- 7
- Issue:
- 1
- ISSN:
- 2520-811X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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