Patent ID: 7750234

Claim:
A photoelectrochemical (PEC) cell, comprising: a) at least one integrated photovoltaic electrode that generates voltage under radiation, the photovoltaic electrode being comprised of: i) a multilayer photovoltaic cell having a stack of semiconductor layers deposited on a conducting substrate, and ii) a transparent, conducting and corrosion-resistant (TCCR) layer on an opposing side of the multilayer material; wherein a first side of the photovoltaic electrode serves as an anode and a second side of the photovoltaic electrode serves as a cathode, the polarity depending on the sequence of p-type and n-type doped layers in the semiconductor layers; b) at least one electrolyte; c) a container that confines electrolyte and the photovoltaic electrode; d) top cover that is substantially transparent to radiation; and, e) at least one membrane that separates the container into two compartments for separate oxidation and reduction reactions, the membrane conducting ions and separating generated oxygen and hydrogen gases, the membrane being installed in a generally perpendicular orientation relative to the photovoltaic cell in order to allow for maximum radiation to reach the photovoltaic electrode, wherein the PEC cell facilitates the interaction of gravity and fluid flow, and wherein gravity drives gas bubbles out of the PEC cell and circulates the electrolyte.