Izindlela zokushiswa kwe-photochemical zokunciphisa ukungcola zifaka phakathi izinqubo ezibandakanya kokubili ukushiswa kwe-photochemical okubangela ukuvuvukala kanye nokungavimbisi. Eyokuqala ivame ukusebenzisa i-oxygen kanye ne-hydrogen peroxide njengama-oxidants futhi ithembele ekukhanyeni kwe-ultraviolet (UV) ukuqala ukushiswa kanye nokubola kokungcola. Eyokugcina, eyaziwa ngokuthi i-photocatalytic oxidation, ngokuvamile ingahlukaniswa njenge-homogeneous kanye ne-heterogeneous catalysis.
Ekuwohlokeni kwe-photocatalytic okungafani, inani elithile lezinto ze-semiconductor ezizwela ukukhanya lifakwa ohlelweni olungcolile, kuhlanganiswe nenani elithile lemisebe yokukhanya. Lokhu kuphumela ekuvuselelweni kwama-pair “e-electron-hole” ebusweni be-semiconductor ezwela ukukhanya ngaphansi kokukhanya. I-oxygen encibilikisiwe, ama-molecule amanzi, nezinye izinto ezifakwe kwi-semiconductor zixhumana nala ma-pair “e-electron-hole”, zigcina amandla amaningi. Lokhu kuvumela izinhlayiya ze-semiconductor ukuthi zinqobe izithiyo zokusabela kwe-thermodynamic futhi zisebenze njengezinto ezibangela ukusabela okuhlukahlukene, zikhiqize ama-radicals ane-oxidative amaningi njenge-•HO. Lawa ma-radical abese enza lula ukonakala kokungcola ngezinqubo ezifana nokwengezwa kwe-hydroxyl, ukufaka esikhundleni, kanye nokudluliselwa kwama-electron.
Izindlela zokushiswa kwe-photochemical zifaka phakathi ukushiswa kwe-photosensitized, ukushiswa kwe-photoexcited, kanye nokushiswa kwe-photocatalytic. Ukushiswa kwe-photochemical kuhlanganisa ukushiswa kwe-chemical kanye nemisebe ukuze kuthuthukiswe izinga kanye namandla okushiswa kwe-oxidation uma kuqhathaniswa nokushiswa kwe-chemical ngakunye noma ukwelashwa kwemisebe. Ukukhanya kwe-ultraviolet kuvame ukusetshenziswa njengomthombo wemisebe ku-photocatalytic oxidation.
Ngaphezu kwalokho, inani elinqunyiwe lama-oxidants njenge-hydrogen peroxide, i-ozone, noma ama-catalyst athile kumele afakwe emanzini. Le ndlela iphumelela kakhulu ekususweni kwama-molecule amancane e-organic, njengedayi, okunzima ukuwabhubhisa futhi abe nobuthi. Ukusabela kwe-photochemical oxidation kukhiqiza ama-radical amaningi asabela kakhulu emanzini, aphazamisa kalula isakhiwo samakhemikhali e-organic.
Isikhathi sokuthunyelwe: Septhemba-07-2023
