Phosphine Oxide Monolayers on SiO₂ Surfaces

A comprehensive study on the physicochemical and electrical properties of Si doped with the molecular doping method

“…c). The height of the step formed, corresponding to the thickness of the deposited layer, was measured and resulted to be less than 2 nm, which coincides with the value of the expected thickness of a monolayer of diethyl‐1‐propylphosphonate . In order to further investigate the formation of the self‐assembled monolayer and its chemical bonding with the substrate, XPS measurements were performed on the as‐deposited samples with a base pressure of 2 × 10 −10 torr.…”

“…Another method recently proposed in literature for the doping of semiconductors is the molecular doping (MD) process [10][11][12][13][14][15]. It is based on the formation of selfassembled layers of dopant-containing molecules on the surface to be doped.…”

Structures and Unexpected Dynamic Properties of Phosphine Oxides Adsorbed on Silica Surfaces

“…They are by‐products of phosphine chemistry, and are generated as stoichiometric co‐products of the Wittig, Appel, and other reactions. They are also indispensable probes for surface acidities of oxides2 and recently received attention in the decomposition of warfare agents 3. Another long‐standing question in the field of immobilized catalysts4 is whether adsorbed phosphine oxides mimic the 31 P MAS (magic angle spinning) NMR signals of phosphine linkers quaternized to form phosphonium salts 5.…”

“…Regarding how phosphine oxides attach to the SiO 2 surface, the PO groups could either bind covalently, or interact with the protons of surface silanol groups 2. 3 The mobility of the adsorbed phosphine oxides on the surface excludes a covalent bond, but we have demonstrated recently that phosphine oxides form rather stable hydrogen‐bonded adducts with H 2 O 2 1.…”

Structures and Dynamics of Secondary and Tertiary Alkylphosphine Oxides Adsorbed on Silica

“…[24] Phosphine oxides are important for many different reasons. [21][22][23][25][26][27][28][29][30] For one, they are unwanted byproducts of phosphine chemistry, for example, in the field of immobilizedc atalysts. [25][26][27][28] They are encountered when Rh catalysts are tethered to as upport by monodentate or chelating phosphine linkers incorporating alkyl chains, [25] and by tetraphosphines with a rigid tetraphenylelement scaffold [26] because Rh catalyzes phosphine oxidation.…”