removal of fingerprints from electrical and optical components. Hydrocarbon production from conversion of into gaseous hydrocarbons. The proposed reaction mechanisms involve the creation of a highly reactive carbon radical from carbon monoxide and carbon dioxide which then reacts with photogenerated protons to ultimately form methane. Efficiencies of -based photocatalysts are low, although nanostructures such as carbon nanotubes and metallic nanoparticles help. Paints ePaint is a less-toxic alternative to conventional antifouling marine paints that generates hydrogen peroxide. Photocatalysis of organic reactions by polypyridyl complexes, porphyrins, or other dyes can produce materials inaccessible by classical approaches. Most photocatalytic dye degradation studies have employed . The anatase form of has higher photon absorption characteristics. Filtration membranes Antifouling coatings for filtration membranes, can act as a separation layer for contaminant degradation. or Cr(VI) removal. Construction Light2CAT was a project funded by the European Commission from 2012 to 2015. It aimed to develop a modified that can absorb visible light and include this modified into construction concrete. The degrades harmful pollutants such as NOx into NO3−. The modified was utilized in Copenhagen and Holbæk, Denmark, and Valencia, Spain. This “self-cleaning” concrete led to a 5-20% reduction in NOx over the course of a year. Quantification ISO 22197-1:2007 specifies a test method for the measurement of removal for materials that contain a photocatalyst or have superficial photocatalytic films. Specific FTIR systems are used to characterize photocatalytic activity or passivity, especially with respect to volatile organic compounds, and representative binder matrices. Mass spectrometry allows measurement of photocatalytic activity by tracking the decomposition of gaseous pollutants such as nitrogen NOx or See also Light harvesting materials Photoelectrochemical cell Photolysis Photocatalytic water splitting Photoredox catalysis Photoelectrochemical oxidation Photosensitizer References Photochemistry Catalysis