Abstract: A photovoltaic device that includes a p-n junction of first type III-V semiconductor material layers, and a window layer of a second type III-V semiconductor material on the light receiving end of the p-n junction, wherein the second type III-V semiconductor material has a greater band gap than the first type III-V semiconductor material, and the window layer of the photovoltaic device has a cross-sectional area of microscale.

Abstract: Methods for setting a resistance include applying a voltage across a memristive device, that exceeds a threshold based on a difference in chemical potential between a first material and a second material, to change a resistance of the memristive device. The memristive device includes a barrier layer of the second material that is formed between two metastable layers of the first material.

Abstract: A photovoltaic device that includes a p-n junction of first type III-V semiconductor material layers, and a window layer of a second type III-V semiconductor material on the light receiving end of the p-n junction, wherein the second type III-V semiconductor material has a greater band gap than the first type III-V semiconductor material, and the window layer of the photovoltaic device has a cross-sectional area of microscale.

Abstract: Memristive devices and methods for setting the resistance of a memristive device include a first mixed conducting layer formed from a first material having a resistance that changes depending on an ion concentration and having multiple coexisting phases from concentration-dependent metastability. A second metastable, mixed conducting layer is formed from the first material. A barrier layer between the first conductor layer and the second conductor layer is formed from a second mixed conducting material having a chemical potential that prevents thermal ion diffusion between the first and second layer. The barrier layer provides an electrical threshold, above which ions are transferred between the first and second layer and below which the resistance of the device is read.

Abstract: A method for fabricating a photovoltaic device includes forming a polycrystalline absorber layer including Cu—Zn—Sn—S(Se) (CZTSSe) over a substrate. The absorber layer is rapid thermal annealed in a sealed chamber having elemental sulfur within the chamber. A sulfur content profile is graded in the absorber layer in accordance with a size of the elemental sulfur and an anneal temperature to provide a graduated bandgap profile for the absorber layer. Additional layers are formed on the absorber layer to complete the photovoltaic device.

Abstract: Zinc oxide compositions as well as techniques for plasmonic enhancement of zinc oxide light absorption for sunscreen applications are provided herein. One example method includes selecting one or more metal particles to be used in conjunction with one or more zinc oxide particles in a sunscreen composition, wherein said selecting is based on the plasmon resonance frequency associated with each of the metal particles, and blending the metal particles and the zinc oxide particles within a medium to create the sunscreen composition.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A composition includes multiple zinc oxide particles suspended within a medium forming sunscreen composition, and coating materials applied to each of the multiple zinc oxide particles in distinct layers via a gradation based on refractive index, wherein each of the coating materials has a refractive index that is between the refractive index of air and the refractive index of zinc oxide, and wherein the coating materials comprise a combination of (i) silicon dioxide, (ii) magnesium fluoride, (iii) one or more fluoropolymers, (iv) aluminum oxide, (v) zinc sulfide, and (vi) titanium dioxide.

Abstract: Zinc oxide compositions as well as techniques for plasmonic enhancement of zinc oxide light absorption for sunscreen applications are provided herein. One example method includes selecting one or more metal particles to be used in conjunction with one or more zinc oxide particles in a sunscreen composition, wherein said selecting is based on the plasmon resonance frequency associated with each of the metal particles; and coating at least one portion of the surface of each of the one or more zinc oxide particles with the metal particles. Another example method includes selecting one or more metal particles to be used in conjunction with one or more zinc oxide particles in a sunscreen composition, wherein said selecting is based on the plasmon resonance frequency associated with each of the metal particles; and blending the metal particles and the zinc oxide particles within a medium to create the sunscreen composition.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A composition includes multiple zinc oxide particles suspended within a medium forming sunscreen composition, and two or more coating materials applied to each of the multiple zinc oxide particles in distinct layers via a gradation based on refractive index, wherein each of the coating materials has a refractive index that is between the refractive index of air and the refractive index of zinc oxide, and wherein the two or more coating materials comprise zinc sulfide and titanium dioxide.

Abstract: Low power combustible gas sensors using a thermocouple design are provided. In one aspect, a combustible gas sensor includes: at least one first electrode; at least one second electrode formed from a dissimilar material from the first electrode; and a catalytic material at an active reaction junction between the first electrode and the second electrode, wherein the active reaction junction between the first electrode and the second electrode forms a thermocouple. A sensing device is including, e.g., multiple sensors, and a method for sensing combustible gas using the present sensors are also provided.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A composition includes multiple zinc oxide particles suspended within a medium forming sunscreen composition, and two or more coating materials applied to each of the multiple zinc oxide particles in distinct layers via a gradation based on refractive index, wherein each of the coating materials has a refractive index that is between the refractive index of air and the refractive index of zinc oxide, and wherein the two or more coating materials comprise one or more fluoropolymers and aluminum oxide.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A composition includes multiple zinc oxide particles suspended within a medium forming sunscreen composition, and two or more coating materials applied to each of the multiple zinc oxide particles in distinct layers via a gradation based on refractive index, wherein each of the coating materials has a refractive index that is between the refractive index of air and the refractive index of zinc oxide.

Abstract: Silver-containing absorbers for photovoltaic devices and techniques for fabrication thereof are provided. In one aspect, a method of forming an ink includes: mixing a silver halide and a solvent to form a first solution; mixing a metal, sulfur, and the solvent to form a second solution; combining the first solution and the second solution to form a precursor solution; and adding constituent components for an absorber material to the precursor solution to form the ink. Methods of forming an absorber film, a photovoltaic device, and the resulting photovoltaic device are also provided.

Abstract: Techniques for solar thermal water purification by recycling photovoltaic reflection losses are provided. In one aspect, a solar thermal water purification system includes: a water purification component for desalinating salt water, the water purification component having multiple stages through which the salt water passes, and condensers in each of the stages; and a photovoltaic component configured to heat the salt water prior to the salt water entering a first stage of the water purification component, wherein desalinated water evaporates and condenses in each of the stages to be collected as pure water. A system using reverse osmosis and a heat-driven water pump is also provided. Methods for water purification are also provided.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A method includes selecting one or more coating materials to be applied to zinc oxide particles in a sunscreen composition, wherein said selecting is based on optical properties of the coating materials, wherein the optical properties comprises at least the refractive index of each of the coating materials, and applying the selected coating materials to the zinc oxide particles to create the sunscreen composition. A composition includes multiple zinc oxide particles suspended within a medium forming sunscreen composition, and one or more coating materials applied to each of the zinc oxide particles, wherein each of the coating materials has a refractive index that is between the refractive index of air and the refractive index of zinc oxide, and wherein at least one of the coating materials incorporates a textured surface.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A method includes selecting one or more coating materials to be applied to zinc oxide particles in a sunscreen composition, wherein selecting is based on optical properties of the coating materials, wherein the optical properties comprises at least the refractive index of each of the coating materials, and applying the selected coating materials to the zinc oxide particles to create the sunscreen composition.

Abstract: Zinc oxide compositions and methods for applying anti-reflective coating on oxide particles for sunscreen applications are provided herein. A method includes selecting two or more coating materials to be applied to zinc oxide particles in a sunscreen composition, wherein selecting is based on optical properties of the coating materials, wherein the optical properties comprises at least the refractive index of each of the coating materials, and applying the selected coating materials to the zinc oxide particles to create the sunscreen composition.

Abstract: Zinc oxide compositions and methods for controlling zinc oxide particle size for sunscreen applications are provided herein. An example composition includes multiple zinc oxide particles, wherein each of the zinc oxide particles is (i) coated with an optical coating material and (ii) of a size that is below a maximum threshold; and a medium layer within which the zinc oxide particles are suspended, wherein the medium layer comprises a mixture of one or more media, and wherein each of the media has a refractive index below a predetermined threshold.

Abstract: Zinc oxide compositions and methods for controlling zinc oxide particle size for sunscreen applications are provided herein. A method includes manipulating the size of multiple zinc oxide particles to be below a maximum threshold; selecting one or more media to be used in a sunscreen composition, wherein said selecting is based on the refractive index of each of the media; and integrating the manipulated zinc oxide particles into the selected media to create the sunscreen composition. A composition includes multiple zinc oxide particles, wherein each of the zinc oxide particles is (i) coated with an optical coating material and (ii) of a size that is below a maximum threshold; and a medium layer within which the zinc oxide particles are suspended, wherein the medium layer comprises a mixture of one or more media, and wherein each of the media has a refractive index below a predetermined threshold.

Abstract: Shell-structured particles for sunscreen applications are provided herein. A composition includes one or more zinc oxide particles constituting a core material in a sunscreen composition, one or more particles coating the one or more zinc oxide particles, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said one or more particles are selected based on a desired absorption spectrum of the sunscreen composition, and an anti-reflective coating applied to the surface of the one or more particles coating the one or more zinc oxide particles.