Abrégé

A method comprising irradiating ultraviolet light on at least one solid composite electrode comprising at least one semiconductor material which is in contact with at least one liquid solution comprising carbon dioxide; wherein at least one proton source is also present in the electrode and/or in the liquid solution comprising carbon dioxide; wherein the irradiating step results in conversion of at least some carbon dioxide into at least one reaction product. High efficiency conversion of carbon dioxide to ethanol can be achieved. The liquid solution can be aqueous, the proton source can be hydroquinone, and the semiconductor material can be zinc sulfide. The solid composite electrode can be a working electrode and used in conjunction with a counter electrode in a photoelectrochemical system. The system can be operated in alternating closed and open circuit mode.

Classes IPC  ?

• C25B 3/04 - Production électrolytique de composés organiques par réduction

Abrégé

A method comprising: irradiating ultraviolet light on at least one solid composite electrode comprising at least one semiconductor material which is in contact with at least one liquid solution comprising carbon dioxide; switching the state of the solid composite electrode between an open circuit mode and a closed circuit mode during the irradiating step; wherein the carbon dioxide is reduced to form an elemental carbon-containing reaction product. Carbon dioxide is photoelectrochemically converted to an elemental carbon-containing reaction product including a carbon rich material which is at least 90 wt.% carbon. The form of the carbon material can be controlled by the time period in the switching step.

Classes IPC  ?

• C25B 3/04 - Production électrolytique de composés organiques par réduction

Abrégé

A method comprising: irradiating ultraviolet light on at least one solid composite electrode comprising at least one semiconductor material (or a colloidal form of the material) which is in contact with at least one liquid solution (e.g., water-based liquid solution) comprising carbon dioxide and at least one polymerization monomer; wherein the carbon dioxide and the polymerization monomer participate in an oligomerization and/or polymerization reaction. Carbon dioxide is photochemically converted at or near a semiconductor material to an oligomer and/or polymer reaction product such as urea-formaldehyde, phenol formaldehyde, or melamine-formaldehyde resin. The semiconductor material can include ZnS and binders can be used such as polytetrafluoroethylene. Acidic or basic conditions can be used. The chain reaction provides for efficient use of the carbon dioxide.

Classes IPC  ?

• C08G 12/12 - UréesThiourées
• C07C 273/04 - Préparation d'urée ou de ses dérivés, c.-à-d. de composés contenant l'un des groupes les atomes d'azote ne faisant pas partie de groupes nitro ou nitroso d'urée, de ses sels, de ses complexes ou de ses composés d'addition à partir de dioxyde de carbone et d'ammoniac
• C08F 2/48 - Polymérisation amorcée par énergie ondulatoire ou par rayonnement corpusculaire par la lumière ultraviolette ou visible