Abstract: At least one embodiment of the present invention provides preparation methods and compositions for nanoarchitectured multi-component materials based on carbon-coated iron-molybdenum mixed oxide as the electrode material for energy storage devices. A sol-gel process containing soluble organics is a preferred method. The soluble organics could become a carbon coating for the mixed oxide after thermal decomposition. The existence of the carbon coating provides the mixed oxide with an advantage in cycling stability over the corresponding carbon-free mixed oxide. For the carbon-coated mixed oxide, a stable cycling stability at high charge/discharge rate (3A/g) can be obtained with Mo/Fe molar ratios ?1/3. The cycling stability and rate capability could be tuned by incorporating a structural additive such as Al2O3 and a conductive additive such as carbon nanotubes. The high rate performance of the multi-component material has been demonstrated in a full device with porous carbons as the positive electrode material.

Abstract: Various embodiments include a method of producing chemically pure and stably dispersed metal and metal-alloy nanoparticle colloids with ultrafast pulsed laser ablation. A method comprises irradiating a metal or metal alloy target submerged in a liquid with ultrashort laser pulses at a high repetition rate, cooling a portion of the liquid that includes an irradiated region, and collecting nanoparticles produced with the laser irradiation and liquid cooling. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beams, a metal or metal alloy target submerged in a liquid, and a liquid circulating system to cool the laser focal volume and collect the nanoparticle products. By controlling various laser parameters, and with optional liquid flow movement, the method provides stable colloids of dispersed metal and metal-alloy nanoparticles. In various embodiments additional stabilizing chemical agents are not required.

Abstract: A rechargeable energy storage device is disclosed. In at least one embodiment the energy storage device includes an air electrode providing an electrochemical process comprising reduction and evolution of oxygen and a capacitive electrode enables an electrode process consisting of non-faradic reactions based on ion absorption/desorption and/or faradic reactions. This rechargeable energy storage device is a hybrid system of fuel cells and ultracapacitors, pseudocapacitors, and/or secondary batteries.

Abstract: A method of fabricating a multi-layered thin film electrochemical device is provided. The method comprises: providing a first target material in a chamber; providing a substrate in the chamber; emitting a first intermittent laser beam directed at the first target material to generate a first plasma, wherein each pulse of the first intermittent laser beam has a pulse duration of about 20 fs to about 500 ps; depositing the first plasma on the substrate to form a first thin film; providing a second target material in the chamber; emitting a second intermittent laser beam directed at the second target material to generate a second plasma, wherein each pulse of the second intermittent laser beam has a pulse duration of about 20 fs to about 500 ps; and depositing the second plasma on or above the first thin film to form a second thin film.

Abstract: Disclosed is a method of producing a chemically pure and stably dispersed organic nanoparticle colloidal suspension using an ultrafast pulsed laser ablation process. The method comprises irradiating a target of an organic compound material in contact with a poor solvent with ultrashort laser pulses at a high repetition rate and collecting the nanoparticles of the organic compound produced. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beam, an organic compound target in contact with a poor solvent, and a solvent circulating system to cool the laser focal volume and collect the produced nanoparticle products. By controlling various laser parameters, and with optional poor solvent flow movement, the method provides stable colloids of dispersed organic nanoparticles in the poor solvent in the absence of any stabilizing agents.

Abstract: A method for generating nanoparticles in a liquid comprises generating groups of ultrafast laser pulses, each pulse in a group having a pulse duration of from 10 femtoseconds to 200 picoseconds, and each group containing a plurality of pulses with a pulse separation of 1 to 100 nanoseconds and directing the groups of pulses at a target material in a liquid to ablate it. The multiple pulse group ablation produces nanoparticles with a reduced average size, a narrow size distribution, and improved production efficiency compared to prior pulsed ablation systems.

Abstract: A method of tuning thin film properties using pulsed laser deposition (PLD) by tuning laser parameters is provided. Various embodiments may be utilized to tune magnetic properties, conductivity or other physical properties. Some embodiments may improve performance of electrochemical devices, for example a thin film electrode may be fabricated resulting in improved reaction speed of a Li ion battery. By way of example, a material property of thin film is tuned by setting a pulse duration. In some embodiments the numbers of laser pulses and laser pulse energy are other laser parameters which may be utilized to tune the film properties. The materials that can be synthesized using various embodiments of the invention include, but are not limited to, metals and metal oxides.

Abstract: A method of fabricating a multi-layered thin film electrochemical device is provided. The method comprises: providing a first target material in a chamber; providing a substrate in the chamber; emitting a first intermittent laser beam directed at the first target material to generate a first plasma, wherein each pulse of the first intermittent laser beam has a pulse duration of about 20 fs to about 500 ps; depositing the first plasma on the substrate to form a first thin film; providing a second target material in the chamber; emitting a second intermittent laser beam directed at the second target material to generate a second plasma, wherein each pulse of the second intermittent laser beam has a pulse duration of about 20 fs to about 500 ps; and depositing the second plasma on or above the first thin film to form a second thin film.

Abstract: A method of forming patterns on transparent substrates using a pulsed laser is disclosed. Various embodiments include an ultrashort pulsed laser, a substrate that is transparent to the laser wavelength, and a target plate. The laser beam is guided through the transparent substrate and focused on the target surface. The target material is ablated by the laser and is deposited on the opposite substrate surface. A pattern, for example a gray scale image, is formed by scanning the laser beam relative to the target. Variations of the laser beam scan speed and scan line density control the material deposition and change the optical properties of the deposited patterns, creating a visual effect of gray scale. In some embodiments patterns may be formed on a portion of a microelectronic device during a fabrication process. In some embodiments high repetition rate picoseconds and nanosecond sources are configured to produce the patterns.

Abstract: Various embodiments include a method of producing chemically pure and stably dispersed metal and metal-alloy nanoparticle colloids with ultrafast pulsed laser ablation. A method comprises irradiating a metal or metal alloy target submerged in a liquid with ultrashort laser pulses at a high repetition rate, cooling a portion of the liquid that includes an irradiated region, and collecting nanoparticles produced with the laser irradiation and liquid cooling. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beams, a metal or metal alloy target submerged in a liquid, and a liquid circulating system to cool the laser focal volume and collect the nanoparticle products. By controlling various laser parameters, and with optional liquid flow movement, the method provides stable colloids of dispersed metal and metal-alloy nanoparticles. In various embodiments additional stabilizing chemical agents are not required.

Abstract: A method of producing compound nanorods and thin films under a controlled growth mode is described. The method involves ablating compound targets using an ultrafast pulsed laser and depositing the ablated materials onto a substrate. When producing compound nanorods, external catalysts such as pre-deposited metal nanoparticles are not involved. Instead, at the beginning of deposition, simply by varying the fluence at the focal spot on the target, a self-formed seed layer can be introduced for nanorods growth. This provides a simple method of producing high purity nanorods and controlling the growth mode. Three growth modes are covered by the present invention, including nanorod growth, thin film growth, and nano-porous film growth.

Abstract: A p-type semiconductor zinc oxide (ZnO) film and a process for preparing the film are disclosed. The film is co-doped with phosphorous (P) and lithium (Li). A pulsed laser deposition scheme is described for use in growing the film. Further described is a process of pulsed laser deposition using transparent substrates which includes a pulsed laser source, a substrate that is transparent at the wavelength of the pulsed laser, and a multi-target system. The optical path of the pulsed laser is arranged in such a way that the pulsed laser is incident from the back of the substrate, passes through the substrate, and then focuses on the target. By translating the substrate towards the target, this geometric arrangement enables deposition of small features utilizing the root of the ablation plume, which can exist in a one-dimensional transition stage along the target surface normal, before the angular width of the plume is broadened by three-dimensional adiabatic expansion.

Abstract: A one-step and room-temperature process for depositing nanoparticles or nanocomposite (nanoparticle-assembled) films of metal oxides such as crystalline titanium dioxide (TiO2) onto a substrate surface using ultrafast pulsed laser ablation of Titania or metal titanium target. The system includes a pulsed laser with a pulse duration ranging from a few femtoseconds to a few tens of picoseconds, an optical setup for processing the laser beam such that the beam is focused onto the target surface with an appropriate average energy density and an appropriate energy density distribution, and a vacuum chamber in which the target and the substrate are installed and background gases and their pressures are appropriately adjusted.

Abstract: A p-type semiconductor zinc oxide (ZnO) film and a process for preparing the film are disclosed. The film is co-doped with phosphorous (P) and lithium (Li). A pulsed laser deposition scheme is described for use in growing the film. Further described is a process of pulsed laser deposition using transparent substrates which includes a pulsed laser source, a substrate that is transparent at the wavelength of the pulsed laser, and a multi-target system. The optical path of the pulsed laser is arranged in such a way that the pulsed laser is incident from the back of the substrate, passes through the substrate, and then focuses on the target. By translating the substrate towards the target, this geometric arrangement enables deposition of small features utilizing the root of the ablation plume, which can exist in a one-dimensional transition stage along the target surface normal, before the angular width of the plume is broadened by three-dimensional adiabatic expansion.

Abstract: A method of ultrashort pulsed laser deposition (PLD) capable of continuously tuning formed-film morphology from that of a nanoparticle aggregate to a smooth thin film completely free of particles and droplets. The materials that can be synthesized using various embodiments of the invention include, but are not limited to, metals, alloys, metal oxides, and semiconductors. A ‘burst’ mode of ultrashort pulsed laser ablation and deposition is provided, where each ‘burst’ contains a train of laser pulses. Tuning of the film morphology is achieved by controlling the burst-mode parameters such as the number of pulses and the time-spacing between the pulses within each burst, the burst repetition rate, and the laser fluence.

Abstract: A method of pulsed laser deposition (PLD) capable of continuously tuning formed-film morphology from that of a nanoparticle aggregate to a smooth thin film free of particles and droplets. The materials that can be synthesized using various embodiments of the invention include, but are not limited to, metals, alloys, metal oxides, and semiconductors. In various embodiments a ‘burst’ mode of ultrashort pulsed laser ablation and deposition is provided. Tuning of the film morphology is achieved by controlling the burst-mode parameters such as the number of pulses and the time-spacing between the pulses within each burst, the burst repetition rate, and the laser fluence. The system includes an ultrashort pulsed laser, an optical system for delivering a focused onto the target surface with an appropriate energy density, and a vacuum chamber in which the target and the substrate are installed and background gases and their pressures are appropriately adjusted.

Abstract: A method of producing compound nanorods and thin films under a controlled growth mode is described. The method involves ablating compound targets using an ultrafast pulsed laser and depositing the ablated materials onto a substrate. When producing compound nanorods, external catalysts such as pre-deposited metal nanoparticles are not involved. Instead, at the beginning of deposition, simply by varying the fluence at the focal spot on the target, a self-formed seed layer can be introduced for nanorods growth. This provides a simple method of producing high purity nanorods and controlling the growth mode. Three growth modes are covered by the present invention, including nanorod growth, thin film growth, and nano-porous film growth.

Abstract: The present invention provides a one-step and room-temperature process for depositing nanoparticles or nanocomposite (nanoparticle-assembled) films of crystalline titanium dioxide (TiO2) onto a substrate surface using ultrafast pulsed laser ablation of Titania or metal titanium target. The system includes a pulsed laser with a pulse duration ranging from a few femtoseconds to a few tens of picoseconds, an optical setup for processing the laser beam such that the beam is focused onto the target surface with an appropriate average energy density and an appropriate energy density distribution, and a vacuum chamber in which the target and the substrate are installed and background gases and their pressures are appropriately adjusted.

Abstract: The present invention provides a one-step process for producing and depositing size-selected nanoparticles onto a substrate surface using ultrafast pulsed laser ablation of solid target materials. The system includes a pulsed laser with a pulse duration ranging from a few femtoseconds to a few tens of picoseconds, an optical setup for processing the laser beam such that the beam is focused onto the target surface with an appropriate average energy density and an appropriate energy density distribution, and a vacuum chamber in which the target and the substrate are installed and the background gases and their pressures are appropriately adjusted.

Abstract: A p-type semiconductor zinc oxide (ZnO) film and a process for preparing the film are disclosed. The film is co-doped with phosphorous (P) and lithium (Li). A pulsed laser deposition scheme is described for use in growing the film. Further described is a process of pulsed laser deposition using transparent substrates which includes a pulsed laser source, a substrate that is transparent at the wavelength of the pulsed laser, and a multi-target system. The optical path of the pulsed laser is arranged in such a way that the pulsed laser is incident from the back of the substrate, passes through the substrate, and then focuses on the target. By translating the substrate towards the target, this geometric arrangement enables deposition of small features utilizing the root of the ablation plume, which can exist in a one-dimensional transition stage along the target surface normal, before the angular width of the plume is broadened by three-dimensional adiabatic expansion.