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1. Distribution and Cycling of Nickel and Nickel Isotopes in the Pacific Ocean

   https://doi.org/10.1029/2024GL111115  

   Bian, X; Yang, S‐C; Raad, R J; Odendahl, C E; Lanning, N T; Sieber, M; Huang, K‐F; Fitzsimmons, J N; Conway, T M; John, S G (August 2024, Geophysical Research Letters)

   Abstract Nickel stable isotopes (δ⁶⁰Ni) provide insight to Ni biogeochemistry in the modern and past oceans. Here, we present the first Pacific Ocean high‐resolution dissolved Ni concentration and δ⁶⁰Ni data, from the US GEOTRACES GP15 cruise. As in other ocean basins, increases in δ⁶⁰Ni toward the surface ocean are observed across the entire transect, reflecting preferential biological uptake of light Ni isotopes, however the observed magnitude of fractionation is larger in the tropical Pacific than the North Pacific Subtropical Gyre. Such surface ocean fractionation by phytoplankton should accumulate isotopically lighter Ni in the deep Pacific, yet we find that North Pacific deep ocean δ⁶⁰Ni is similar to previously reported values from the deep Atlantic. Finally, we find that seawater dissolved δ⁶⁰Ni in regions with hydrothermal input can be either higher or lower than background deep ocean δ⁶⁰Ni, depending on vent geochemistry and proximity. 

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2. Decarbonylative thioetherification by nickel catalysis using air- and moisture-stable nickel precatalysts

   Liu, Chengwei; Szostak, Michal (February 2018, Chemical communications)

   A general, highly selective method for decarbonylative thioetherification of aryl thioesters by C–S cleavage is reported. These reactions are promoted by a commercially-available, userfriendly, inexpensive, air- and moisture-stable nickel precatalyst. The process occurs with broad functional group tolerance, including free anilines, cyanides, ketones, halides and aryl esters, to efficiently generate thioethers using ubiquitous carboxylic acids as ultimate cross-coupling precursors (cf. conventional aryl halides or pseudohalides). Selectivity studies and site-selective orthogonal cross-coupling/thioetherification are described. This thioester activation/coupling has been highlighted in the expedient synthesis of biorelevant drug analogues. In light of the synthetic utility of thioethers and Ni(II) precatalysts, we anticipate that this user-friendly method will be of broad interest. 

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3. Electrochemical Oxide Growth on Nickel and Commercial Nickel Alloys: Influence of Chromium and Molybdenum

   https://doi.org/10.1149/1945-7111/acd7a6  

   Kretzmer, Isaac; Stuve, Eric M. (June 2023, Journal of The Electrochemical Society)

   Nickel-chromium-molybdenum (NiCrMo) alloys are well-known for having exceptional corrosion resistance, but their electrocatalytic properties have not been extensively studied. In this paper, the development of electro-active nickel-oxyhydroxide (NiOOH) phases and kinetics of the oxygen evolution reaction (OER) have been examined on alloys G35, B3, and C276 in alkaline electrolyte at 25 °C. Reproducible oxide layers were grown by potential cycling between 0.85 and 1.52 V vs RHE up to 600 cycles, and the transition between Ni(OH) 2 and NiOOH was monitored by cyclic voltammetry throughout. Onset potentials, Tafel slopes, and turnover frequencies (TOF) were measured at OER overpotentials between 270 and 390 mV. Alloys with dissimilar Cr:Mo ratios had significantly higher electrochemical surface area and increased γ -NiOOH formation, suggesting higher metal dissolution rates. The equal Cr:Mo concentration alloy and pure Ni developed a primarily β -NiOOH surface, and had 1.8–2.0 times larger TOF values than those containing significant γ -NiOOH. The NiCrMo alloys required smaller overpotentials (54–80 mV) to produce 10 mA cm −2 of OER current, and had comparable Tafel slopes to pure Ni. The findings here indicate a β -NiOOH-developed surface to be more OER-active than a γ -NiOOH-developed surface, and suggest certain NiCrMo alloys have promise as OER electrocatalysts. 

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4. Plasma-enhanced thermal atomic layer deposition of nickel oxide and nickel carbide thin films

   https://doi.org/10.1016/j.tsf.2025.140738  

   Paulette, Holden; Hathaway, Evan; Wickramagedara, Agra; Gonzalez-Rodriguez, Roberto; Coffer, Jeffery L; Lin, Yuankun; Cui, Jingbiao (July 2025, Thin Solid Films)
5. Nickel‐containing magnetoceramics from water vapor‐assisted pyrolysis of polysiloxane and nickel 2,4‐pentanedionate

   https://doi.org/10.1111/jace.16738  

   Yang, Ni; Gao, Min; Li, Jiefang; Lu, Kathy (August 2019, Journal of the American Ceramic Society)

   Abstract In this study, novel ferromagnetic Ni‐containing silicon oxycarbide (SiOC–Ni) was successfully fabricated from a base polysiloxane (PSO) with the addition of nickel 2,4‐pentanedionate. The resultant SiOC–Ni nanocomposite consists of in situ formed Ni nanocrystallites with a small amount of NiO uniformly dispersed in the amorphous SiOC matrix, and the corresponding nanocrystallite size increases with the increase of the pyrolysis temperature. The formation of nickel silicides (Ni_xSi_y) is completely suppressed by the effect of water vapor during the pyrolysis. The fundamental phase evolution process and mechanisms are explained. In an argon atmosphere, the SiOC–Ni materials pyrolyzed at 900°C are stable up to 1000°C with less than 6 wt% weight loss; they exhibit desirable electrical conductivity up to ~900°C with the highest electrical conductivity at ~247 S/m. This series of SiOC–Ni materials also demonstrates exciting ferromagnetic behaviors. Their new semiconducting behavior with soft ferromagnetism presents promising application potentials for magnetic sensors, transformers, actuators, etc. 

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