A gradient energy system includes a membrane module including a first section, a second section, and a membrane separating the first section and the second section. A first gas may be provided within the first section. A second gas may be provided within the second section. The membrane module may be configured such that a differential associated with the first gas and the second gas generates a fluid pressure force or an electrical current. A method of recovering energy from gradients of gas mixtures may include providing a first gas to a first section of a membrane module, providing a second gas to a second section of the membrane module, which may be separated from the first section by a membrane, and/or recovering energy generated via a differential between the first gas and the second gas.

The present disclosure relates to nanocomposites of CuO/Cu.sub.2O and continuous flow solar reactors. The nanocomposites can be utilized as a photocatalyst and can be incorporated into photoelectrochemical devices. The described devices, systems, and methods can be used for converting CO.sub.2 into one or more alcohols and other small organics with the use of solar energy and electricity. Other embodiments are described.

A sample concentrator includes a lower frame and an upper frame coupled to overlap each other, wherein the lower frame includes a first electrode buffer channel and a second electrode buffer channel spaced apart from each other, a main channel formed in the lower frame and connecting the first electrode buffer channel to the second buffer channel, a first ion exchange membrane located between the first electrode buffer channel and the main channel, a second ion exchange membrane located between the second electrode buffer channel and the main channel, a first electrode electrically connected to the main channel with the first electrode buffer channel interposed therebetween, and a second electrode electrically connected to the main channel with the second electrode buffer channel interposed therebetween.

The present disclosure relates to a conjugated polyelectrolyte-grafted membrane, which is obtained by fixing a conjugated polyelectrolyte (CPE) capable of generating active oxygen under visible light irradiation to a membrane through crosslinking, and can remove contaminants in water, while reducing bio-fouling on the surface of the membrane, by generating active oxygen through a photocatalytic reaction of the conjugated polyelectrolyte (CPE), as well as to a method for manufacturing the same. The method for manufacturing a conjugated polyelectrolyte-grafted membrane includes the steps of: preparing a conjugated polyelectrolyte (CPE); coating a conjugated polyelectrolyte (CPE) on the surface of a membrane; and carrying out crosslinking of the conjugated polyelectrolyte (CPE) with the surface of the membrane.

A boron-containing proton-exchange solid support may include a proton-exchange solid support comprising an oxygen atom and a tetravalent boron-based acid group comprising a boron atom covalently bonded to the oxygen atom.

A proton exchange membrane includes a porous structural framework and a boron-based acid group bonded to the porous structural framework. The porous structural framework may be formed of an amorphous or crystalline inorganic material and/or a synthetic or natural polymer. The boron-based acid group may be a tetravalent boric acid derivative, such as a cyclic boric acid derivative, borospiranic acid, or a borospiranic acid derivative. The boron-based acid group may be the reaction product of boric acid or a boric acid derivative and a poly-hydroxy compound.

An ionically conductive thin film composite (TFC) membrane is described. The low cost, high performance TFC membrane comprises a micropous support membrane, and a hydrophilic ionomeric polymer coating layer on a surface of the microporous support membrane. The hydrophilic ionomeric polymer coating layer is ionically conductive. The ionomeric polymer can also be present in the micropores of the support membrane. Methods of making the membrane and redox flow battery system incorporating the TFC membrane are also described.

Dye-sensitized ion-pumping membranes and methods of preparing said membranes are described herein. A regenerative and reversible photoactive dye is covalently-bonded to membrane or separator for ion-pumping. The photoactive dye-functionalized membranes can be arranged with other ion-exchange membranes, which serve as selective contacts to afford photovoltaic action and therefore form a power-producing membrane that pumps ions for use in driving an ion-exchange or ion-transport process, such as desalination and electrodialysis.

A crosslinkable copolymer is provided. The crosslinkable copolymer has pendant cationic nitrogen-containing groups with some, but not all, of these pendant groups further including a (meth)acryloyl group. The (meth)acryloyl groups can react to form a crosslinked copolymer that is ionically conductive. The crosslinked copolymer can be used to provide an anion exchange membrane that can be used in electrochemical cells such as fuel cells, electrolyzers, batteries, and electrodialysis cells.

A method for separating ionic species from an analyte solution to form a fractionated sample, the method comprising contacting the analyte solution with an ion-exchanger that is selectively permeable to ionic species of either a positive or negative charge, contacting an opposing side of the ion-exchanger with a draw solution, wherein the draw solution comprises adsorber particles dispersed in a liquid carrier, establishing a concentration gradient across the ion-exchanger to allow at least some ionic species from the analyte solution to permeate through the ion-exchanger to the draw solution, adsorbing ionic species that permeate from the analyte solution onto the adsorber particles, separating adsorber particles having the ionic species adsorbed thereto from at least part of the draw solution, and eluting the ionic species from the separated adsorber particles to form a fractionated analyte sample comprising eluted ionic species.