Abstract: A photoelectrosynthetically active heterostructure (PAH) is manufactured by forming or providing cavities in an electrically insulating material; forming or providing an electrically conductive layer on a side of the electrically insulating material; depositing an electrocatalyst cathode layer in the cavities; depositing one or more layers of light-absorbing semiconductor material in the cavities; depositing an electrocatalyst anode layer in the cavities; removing the layer of electrically conductive metal; and forming a hydrogen permeable layer over the electrocatalyst cathode layer. The one or more layers of light-absorbing semiconductor material can form a p-n junction or Schottky junction. The PAH can be used in photoelectrosynthetic processes to produce desired products, such as reduction product (e.g., methane gas, methanol, or carbon monoxide) from carbon dioxide and liquid waste streams.

Abstract: A photoelectrosynthetically active heterostructure (PAH) is manufactured by forming or providing cavities in an electrically insulating material; forming or providing an electrically conductive layer on a side of the electrically insulating material; depositing an electrocatalyst cathode layer in the cavities; depositing one or more layers of light-absorbing semiconductor material in the cavities; depositing an electrocatalyst anode layer in the cavities; removing the layer of electrically conductive metal; and forming a hydrogen permeable layer over the electrocatalyst cathode layer. The one or more layers of light-absorbing semiconductor material can form a p-n junction or Schottky junction. The PAH can be used in photoelectrosynthetic processes to produce desired products, such as reduction product (e.g., methane gas, methanol, or carbon monoxide) from carbon dioxide and liquid waste streams.

Abstract: A two-step process, consisting of a photoelectrosynthetic process combined with a thermochemical process, is configured to produce a reduction product (e.g., methane gas, methanol, or carbon monoxide) from carbon dioxide and liquid waste streams. In a first step, photoelectrosynthetically active heterostructures (PAHs) and sunlight are used to drive oxidation/reduction reactions in which one primary product is hydrogen gas. In the second step, hydrogen generated in the first step is thermally catalytically reacted with carbon dioxide to form a reduction product from carbon dioxide (e.g., CO, formaldehyde, methane, or methanol). Synthesis gas (CO and H2) can be further reacted to form alkanes. The methods and systems may employ PAHs known in the art or improved PAHs having lower costs, improved stability, solar energy conversion efficiency, and/or other desired attributes as disclosed herein.

Abstract: Disclosed is a polymer coating that can be used to stabilize the operation of electroactive devices. The coating can be electrically conductive and optically transparent. The coating can be a polymer such as PEDOT:PSS, and the polymer can be doped or undoped. The coating can help facilitate PEC and PS reactions that form electrical energy or other chemicals. The coating can additionally be used for coating other electroactive devices.