All articles starting with P
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Photocatalytic hydrogen evolution
Photocatalytic hydrogen evolution is the production of hydrogen from water using light-activated semiconductor particles or electrodes, a field begun with Fujishima and Honda's 1972 TiO₂ work.
Photocatalytic hydrogen peroxide production from water and oxygen
Photocatalytic hydrogen peroxide production from water and oxygen is an artificial photosynthesis process that uses sunlight and a semiconductor photocatalyst to make hydrogen peroxide, a sustainable alternative to the anthraquinone process.
Photocatalytic lignin depolymerization
Photocatalytic lignin depolymerization uses light-activated catalysts to break the bonds of lignin, the aromatic polymer in plant cell walls, into aromatic compounds under mild conditions.
Photocatalytic methane conversion
Photocatalytic methane conversion uses light-activated semiconductor photocatalysts to turn methane directly into methanol, ethane, and hydrogen under mild conditions instead of high temperatures, first reported in 1978.
Photocatalytic methane oxidation
Photocatalytic methane oxidation is the light-driven conversion of methane chiefly to methanol, using semiconductor catalysts at ambient conditions to avoid the heat and pressure of thermal routes.
Photocatalytic nitrogen deletion of indoles
Photocatalytic nitrogen deletion of indoles is a skeletal editing reaction, reported by Richmond Sarpong's group in 2021, that removes an indole's nitrogen with blue light.
Photocatalytic nitrogen reduction
Photocatalytic nitrogen reduction (PNR) is a light-driven method in which semiconductor catalysts convert atmospheric nitrogen into ammonia under ambient conditions, pursued as a milder alternative to the Haber-Bosch process.
Photocatalytic olefin isomerization via energy transfer
Photocatalytic olefin isomerization via energy transfer is a synthetic method in which a visible-light photocatalist transfers triplet energy to an alkene, enabling contra-thermodynamic E-to-Z conversion.
Photocatalytic overall water splitting by Al-doped SrTiO3
Al-doped SrTiO3 (SrTiO3:Al, also written Al:STO) is a benchmark photocatalyst powder that splits water into hydrogen and oxygen under ultraviolet light without any applied bias.
Photocatalytic oxidation
Photocatalytic oxidation, or selective photocatalytic oxidation, is a method in which light-activated TiO2 generates radicals that mineralize pollutants or selectively oxidize organics to value-added products.
Photocatalytic oxidative coupling
Photocatalytic oxidative coupling is a photochemical method that uses light and a photocatalyst to join two molecules, forming new carbon-carbon or carbon-heteroatom bonds under mild conditions.
Photocatalytic plastic reforming
Photocatalytic plastic reforming, also called plastic photoreforming, uses sunlight and a photocatalyst to convert plastic waste into hydrogen fuel and value-added chemicals at ambient temperature and pressure.
Photocatalytic plastic upcycling
Photocatalytic plastic upcycling is the use of light-activated catalysts, typically driven by sunlight, to convert plastic waste into value-added chemicals and fuels at ambient temperature and pressure.
Photocatalytic reduction
Photocatalytic reduction is a class of light-driven chemical reactions in which a photocatalyst absorbs photons and uses excited electrons to reduce CO2, water, or protons, mainly for solar fuel production.
Photocatalytic reforming
Photocatalytic reforming, or photoreforming, is a sunlight-driven process in which a semiconductor photocatalyst oxidizes biomass or organic waste to produce hydrogen fuel at ambient temperature and pressure.
Photocatalytic selective oxidation
Photocatalytic selective oxidation is a light-activated catalytic method that oxidizes a specific functional group or C–H bond of an organic substrate, typically using oxygen as the oxidant.
Photocatalytic synthesis
Photocatalytic synthesis is a method of making organic compounds and materials in which a photocatalyst absorbs light and uses that energy to drive bond-forming reactions under mild conditions.
Photocatalytic water oxidation
Photocatalytic water oxidation is the light-driven conversion of water to oxygen by a photocatalyst, the oxidative half-reaction of artificial photosynthesis and the rate-determining step of overall water splitting.
Photocatalytic water purification
Photocatalytic water purification is a water treatment method in which light-activated semiconductor catalysts, usually titanium dioxide, degrade organic pollutants and inactivate pathogens, often using sunlight.
Photocatalytic water splitting
Photocatalytic water splitting uses light-activated semiconductor catalysts to split water into hydrogen and oxygen, storing solar energy as fuel; the record efficiency is 9.2% under concentrated light, and commercialization is thought to require 10%.
Photocatalytic β-scission of alcohols
Photocatalytic β-scission of alcohols is a light-driven reaction in which an alcohol forms an alkoxy radical that cleaves a carbon–carbon bond, yielding a carbonyl compound and a carbon radical.
Photocathode
A photocathode is a photoemissive surface, usually of alkali metals or semiconductors in a vacuum device, that converts photons into electrons via the photoelectric effect.
Photochemical alkene isomerization
Photochemical alkene isomerization is a photochemical process in which light changes a carbon–carbon double bond between E and Z configurations, chiefly to reach the less stable Z isomer.
Photochemical aziridination
Photochemical aziridination is the synthesis of aziridines, three-membered nitrogen-containing heterocycles, by light-driven generation of nitrenes that add to alkenes; a landmark 2016 method used visible light and an iridium photocatalyst.
Photochemical C–H functionalization
Photochemical C–H functionalization uses light-driven chemistry to convert carbon–hydrogen bonds directly into carbon–heteroatom or carbon–carbon bonds, typically via radical intermediates under mild conditions, enabling late-stage modification of drugs and natural products.
Photochemical C–H functionalization of peptides
Photochemical C–H functionalization of peptides is a set of light-driven methods that convert unreactive carbon–hydrogen bonds in peptides into new bonds, without pre-installed functional groups.
Photochemical carbene transfer
Photochemical carbene transfer is a family of metal-free organic reactions in which light generates a carbene from a diazo compound or diazirine, enabling cyclopropanation and C–H or X–H insertion.
Photochemical carboazidation
Photochemical carboazidation is a light-driven alkene difunctionalization reaction that installs a carbon group and an azido group across a carbon–carbon double bond, typically combining alkene, radical precursor, and azide source.
Photochemical curing
Photochemical curing is a manufacturing method that uses light, typically ultraviolet, to polymerize liquid resins, adhesives, coatings, and hydrogels into solids, curing most materials fully in 1 to 30 seconds and enabling high-build-rate 3D printing.
Photochemical etching
Photochemical etching, also called photochemical machining or photochemical milling, patterns thin metal sheets by printing a photoresist mask and chemically dissolving exposed areas, producing burr-free, stress-free flat parts used for IC leadframes, screens, and shims.