Few layer 2D pnictogens catalyze the alkylation of soft nucleophiles with esters
Group 15 elements in zero oxidation state (P, As, Sb and Bi), also called pnictogens, are rarely used in catalysis due to the difficulties associated in preparing well–structured and stable materials. Here, we report on the synthesis of highly exfoliated, few layer 2D phosphorene and antimonene in zero oxidation state, suspended in an ionic liquid, with the native atoms ready to interact with external reagents while avoiding aerobic or aqueous decomposition pathways, and on their use as efficient catalysts for the alkylation of nucleophiles with esters. The few layer pnictogen material circumvents the extremely harsh reaction conditions associated to previous superacid–catalyzed alkylations…
Gitteröffnung durch reduktive kovalente Volumen‐Funktionalisierung von schwarzem Phosphor
Eine chemisch-reduktive Volumen-Funktionalisierung von dünnlagigem schwarzem Phosphor (BP) gelang unter Verwendung von BP-Interkalationsverbindungen. Durch eine effektive reduktive Aktivierung wurde die kovalente Funktionalisierung des geladenen BP mit Alkylhalogeniden erzielt, wobei eine Öffnung des BP-Gitters und ein höherer Funktionalisierungsgrad als bei neutralen Reaktionsrouten resultieren.
Lattice Opening upon Bulk Reductive Covalent Functionalization of Black Phosphorus
The chemical bulk reductive covalent functionalization of thin-layer black phosphorus (BP) using BP intercalation compounds has been developed. Through effective reductive activation, covalent functionalization of the charged BP by reaction with organic alkyl halides is achieved. Functionalization was extensively demonstrated by means of several spectroscopic techniques and DFT calculations; the products showed higher functionalization degrees than those obtained by neutral routes.
Fabrication of layered nanostructures by successive electron beam induced deposition with two precursors: protective capping of metallic iron structures
We report on the stepwise generation of layered nanostructures via electron beam induced deposition (EBID) using organometallic precursor molecules in ultra-high vacuum (UHV). In a first step a metallic iron line structure was produced using iron pentacarbonyl; in a second step this nanostructure was then locally capped with a 2-3 nm thin titanium oxide-containing film fabricated from titanium tetraisopropoxide. The chemical composition of the deposited layers was analyzed by spatially resolved Auger electron spectroscopy. With spatially resolved x-ray absorption spectroscopy at the Fe L₃ edge, it was demonstrated that the thin capping layer prevents the iron structure from oxidation upon e…