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Phase-change memory is an emerging type of nonvolatile memory that shows a strong presence in the data-storage market. This technology has also recently attracted significant research interest in the development of non-Von Neumann computing architectures such as in-memory and neuromorphic computing. Research in these areas has been primarily motivated by the scalability potential of phase-change materials in crossbar architectures and their compatibility with industrial nanofabrication processes. In this work, we have developed crossbar phase-change memory arrays through the electrodeposition of GeSbTe (GST). We show that GST can be electrodeposited in nanofabricated TiN crossbar arrays using a scalable process. Various characterization techniques, such as atomic force microscopy (AFM), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX) were used to study electrodeposited materials in these arrays. Phase-switching tests of electrodeposited materials have shown a resistance switching ratio of 2 orders of magnitude with an endurance of around 80 cycles. Demonstrating crossbar phase-change memories via electrodeposition paves the way toward using this technique for developing scalable memory arrays involving electrodeposited materials for passive selectors and phase-switching devices.

in Wiley InterScience (www.interscience.wiley.com).The synthesis of two NiMo/Al 2 O 3 catalysts by the supercritical carbon dioxide/methanol deposition (NiMo-SCF) and the conventional method of wet coimpregnation (NiMo-IMP) were conducted. The results of the physical and chemical characterization techniques (adsorption-desorption of nitrogen, oxygen chemisorption, XRD, TPR, TEM, and EDAX) for the NiMo-SCF and NiMo-IMP demonstrated high and uniform dispersed deposition of Ni and Mo on the Al 2 O 3 support for the newly developed catalyst. The hydrodesulfurization (HDS) of fuel model compound, dibenzothiophene, was used in the evaluation of the NiMo-SCF catalyst vs. the commercial catalyst (NiMo-COM). Higher conversion for the NiMo-SCF catalyst was obtained. The kinetic analysis of the reaction data was carried out to calculate the reaction rate constant of the synthesized and commercial catalysts in the temperature rang of 543-603 K. Analysis of the experimental data using Arrhenius' law resulted in the calculation of frequency factor and activation energy of the HDS for the two catalysts. V

The synthesis of NiMo/Al-HMS nanocatalyst (2.3 wt % Ni and 9.4 wt % Mo) via supercritical CO2−methanol deposition and conventional wet coimpregnation was investigated. The characterization of both catalysts by adsorption−desorption of nitrogen, oxygen chemisorptions, XRD, TPR, and TEM indicated that Ni and Mo highly and uniformly dispersed on the Al-HMS support. The results of activity of the NiMo/Al-HMS nanocatalyst in the hydrodesulfurization of dibenzothiophene demonstrated higher conversion for the NiMo/Al-HMS nanocatalyst in contrast to conventional catalyst. The reaction rate constants at 330 °C for the NiMo/Al-HMS nanocatalyst and the conventional one were calculated to be 3.65 × 10−5 and 2.20 × 10−5 (mol /g cat. min), respectively. Moreover, the newly developed nanocatalyst is less inhibited than the conventional catalyst by aromatics such as toluene.

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