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: Semitransparent chalcogen solar cells and techniques for fabrication thereof are provided. In one aspect, a method of forming a solar cell includes: forming a first transparent contact on a substrate; depositing an n-type layer on the first transparent contact; depositing a p-type chalcogen absorber layer on the n-type layer, wherein a p-n junction is formed between the p-type chalcogen absorber layer and the n-type layer; depositing a protective interlayer onto the p-type chalcogen absorber layer, wherein the protective interlayer fully covers the p-type chalcogen absorber layer; and forming a second transparent contact on the interlayer, wherein the interlayer being disposed between the p-type chalcogen absorber layer and the second transparent contact serves to protect the p-n junction during the forming of the second transparent contact. Solar cells and other methods for formation thereof are also provided.

Abstract: Selenium-fullerene heterojunction solar cells and techniques for fabrication thereof are provided. In one aspect, a method of forming a solar cell includes: forming a front contact on a substrate; depositing an n-type semiconducting layer on the front contact, wherein the n-type semiconducting layer comprises a fullerene or fullerene derivative; forming a p-type chalcogen absorber layer on the n-type semiconducting layer; depositing a high workfunction material onto the p-type chalcogen absorber layer, wherein the high workfunction material has a workfunction of greater than about 5.2 electron volts; and forming a back contact on the high workfunction material. Solar cells and other methods for formation thereof are also provided.

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: Techniques for precisely controlling the composition of volatile components (such as sulfur (S), selenium (Se), and tin (Sn)) of chalcogenide semiconductors in real-time—during production of the material are provided. In one aspect, a method for forming a chalcogenide semiconductor material includes providing a S source(s) and a Se source(s); heating the S source(s) to form a S-containing vapor; heating the Se source(s) to form a Se-containing vapor; passing a carrier gas first through the S-containing vapor and then through the Se-containing vapor, wherein the S-containing vapor and the Se-containing vapor are transported via the carrier gas to a sample; and contacting the S-containing vapor and the Se-containing vapor with the sample under conditions sufficient to form the chalcogenide semiconductor material. A multi-chamber processing apparatus is also provided.

Abstract: Shell-structured particles for sunscreen applications are provided herein. A method includes selecting one or more particles to serve as a core material in a sunscreen composition, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said selecting is based on a desired absorption spectrum of the sunscreen composition; coating the one or more particles with at least one layer of zinc oxide.

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.

Abstract: Shell-structured particles for sunscreen applications are provided herein. A method includes selecting one or more particles to serve as a core material in a sunscreen composition, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said selecting is based on a desired absorption spectrum of the sunscreen composition; coating the one or more particles with at least one layer of zinc oxide.

Abstract: Semitransparent chalcogen solar cells and techniques for fabrication thereof are provided. In one aspect, a method of forming a solar cell includes: forming a first transparent contact on a substrate; depositing an n-type layer on the first transparent contact; depositing a p-type chalcogen absorber layer on the n-type layer, wherein a p-n junction is formed between the p-type chalcogen absorber layer and the n-type layer; depositing a protective interlayer onto the p-type chalcogen absorber layer, wherein the protective interlayer fully covers the p-type chalcogen absorber layer; and forming a second transparent contact on the interlayer, wherein the interlayer being disposed between the p-type chalcogen absorber layer and the second transparent contact serves to protect the p-n junction during the forming of the second transparent contact. Solar cells and other methods for formation thereof are also provided.

Abstract: Selenium-fullerene heterojunction solar cells and techniques for fabrication thereof are provided. In one aspect, a method of forming a solar cell includes: forming a front contact on a substrate; depositing an n-type semiconducting layer on the front contact, wherein the n-type semiconducting layer comprises a fullerene or fullerene derivative; forming a p-type chalcogen absorber layer on the n-type semiconducting layer; depositing a high workfunction material onto the p-type chalcogen absorber layer, wherein the high workfunction material has a workfunction of greater than about 5.2 electron volts; and forming a back contact on the high workfunction material. Solar cells and other methods for formation thereof are also provided.

Abstract: A method of fabricating a memristive structure for symmetric modulation between resistance states is presented. The method includes forming a first electrode and a second electrode over an insulating substrate, forming an anode contacting the first and second electrodes, forming an ionic conductor over the anode, forming a cathode of the same material as the anode over the ionic conductor, forming a third electrode over the cathode, and enabling bidirectional transport of ions between the anode and cathode resulting in a resistance adjustment of the memristive structure, the anode and the cathode being formed from metastable mixed conducting materials with ion concentration dependent conductivity.

Abstract: Shell-structured particles for sunscreen applications are provided herein. A method includes selecting one or more particles to serve as a core material in a sunscreen composition, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said selecting is based on a desired absorption spectrum of the sunscreen composition; coating the one or more particles with at least one layer of zinc oxide. A composition includes selecting one or more particles to serve as a coating layer in a sunscreen composition, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said selecting is based on a desired absorption spectrum of the sunscreen composition; and coating one or more zinc oxide particles with the one or more selected particles.

Abstract: Variable-resistance devices and methods of forming the same include a variable-resistance layer, formed between a first terminal and a second terminal, that varies in resistance based on an oxygen concentration in the variable-resistance layer. An electrolyte layer that is stable at room temperature and that conducts oxygen ions in accordance with an applied voltage is positioned over the variable-resistance layer. A gate layer is configured to apply a voltage on the electrolyte layer and the variable-resistance layer and is positioned over the electrolyte layer.

Abstract: Kesterite-based photovoltaic devices formed on flexible ceramic substrates are provided. In one aspect, a method of forming a photovoltaic device includes the steps of: forming a back contact on a flexible ceramic substrate; forming a kesterite absorber layer on a side of the back contact opposite the flexible ceramic substrate; annealing the kesterite absorber layer; forming a buffer layer on a side of the kesterite absorber layer opposite the back contact; and forming a transparent front contact on a side of the buffer layer opposite the kesterite absorber layer. A roll-to-roll-based method of forming a photovoltaic device and a photovoltaic device are also provided.

Abstract: Techniques for minimizing loss of volatile components during thermal processing of kesterite films are provided. In one aspect, a method for annealing a kesterite film is provided. The method includes: placing a cover over the kesterite film; and annealing the cover and the kesterite film such that, for an entire duration of the annealing, the cover is at a temperature T1 and the kesterite film is at a temperature T2, wherein the temperature T1 is greater than or equal to the temperature T2. Optionally, during a cool down segment of the annealing, conditions can be reversed to have the temperature T1 be less than the temperature T2. A solar cell and method for formation thereof using the present annealing techniques are also provided.

Abstract: Vacuum annealing-based techniques for forming perovskite materials are provided. In one aspect, a method of forming a perovskite material is provided. The method includes the steps of: depositing a metal halide layer on a sample substrate; and vacuum annealing the metal halide layer and methylammonium halide under conditions sufficient to form methylammonium halide vapor which reacts with the metal halide layer and forms the perovskite material on the sample substrate. A perovskite-based photovoltaic device and method of formation thereof are also provided.

Abstract: A neuromorphic device includes a first electrode layer arranged on a substrate, and an electrolyte layer arranged on the first electrode layer. The electrolyte layer includes a solid electrolyte material. The neuromorphic device further includes an ion permeable, electrically conductive membrane arranged on the electrolyte layer and an ion intercalation layer arranged on the ion permeable, electrically conductive membrane. The neuromorphic device includes a second electrode layer arranged on the ion intercalation layer.

Abstract: A neuromorphic device includes a first electrode layer arranged on a substrate, and an electrolyte layer arranged on the first electrode layer. The electrolyte layer includes a solid electrolyte material. The neuromorphic device further includes an ion permeable, electrically conductive membrane arranged on the electrolyte layer and an ion intercalation layer arranged on the ion permeable, electrically conductive membrane. The neuromorphic device includes a second electrode layer arranged on the ion intercalation layer.

Abstract: An integrated kesterite (e.g., CZT(S,Se)) photovoltaic device and battery is provided. In one aspect, a method of forming an integrated photovoltaic device and battery includes: forming a photovoltaic device having a substrate, an electrically conductive layer, an absorber layer, a buffer layer, a transparent front contact, and a metal grid; removing the substrate and the electrically conductive layer from the photovoltaic device to expose a backside surface of the absorber layer; forming at least one back contact on the backside surface of the absorber layer; and integrating the photovoltaic device with a battery, wherein the integrating includes connecting i) a positive contact of the battery with the back contact on the backside surface of the absorber layer and ii) a negative contact of the battery with the metal grid on the transparent front contact. An integrated photovoltaic device and battery is also provided.