Patent ID: 9567680
Date: 2017-02-14
CPC Classifications: C01B,C25B,Y02E,Y02P,Y10T

Claim:
1. A composite protective layer for a photoelectrode structure, the composite protective layer comprising: a chemical protective layer, wherein the chemical protective layer is a metal and comprises at least one metal selected from Group 4, Group 5, Group 11, Group 13, and Group 14 of the Periodic Table of the Elements, and an alloy thereof; and a physical protective layer, wherein the physical protective layer comprises carbon or a metal comprising at least one selected from at least one metal selected from Group 5, Group 11, and Group 13, an alloy thereof, and stainless steel, wherein the chemical protective layer has a corrosion rate of 0.1 Coulombs per square centimeter per 10 hours or less when evaluated at a water decomposition potential, and wherein the physical protective layer has moisture transmittance rate of 0.001 grams per square meter per day or less and has an electrical conductivity, wherein the chemical protective layer comprises at least one metal selected from tantalum, niobium, titanium, gallium, zirconium, copper, hafnium, aluminum, and indium, and an alloy thereof, and the metal of the physical protective layer comprises at least one selected from copper, stainless steel, tantalum, niobium, and titanium, an alloy thereof, and stainless steel.