Novel Quinone-Based Couples for Flow Batteries

Flow batteries are of interest for low-cost grid-scale electrical energy storage in the face of rising electricity production from intermittent renewables like wind and solar. We report on investigations of redox couples based on the reversible protonation of small organic molecules called quinones. These molecules can be very inexpensive and may therefore offer a low cost per kWh of electrical energy storage. Furthermore they are known to rapidly undergo oxidation and reduction with high reversibility under some conditions, suggesting the possibility of high current density operation, which could lead to low cost per kW. We report cyclic voltammetry measurements for 1,4-parabenzoquinone in neutral pH aqueous solution using a three-electrode setup. We report full fuel cell measurements as well, utilizing p-benzoquinone in an acidic solution as a positive electrode material and a hydrogen negative electrode, where current densities in excess of 240 mA $cm^{-2}$ have been achieved to date. These initial results indicate that the quinone/hydroquinone redox couple is a promising candidate for use in redox flow batteries.Engineering and Applied Science

Benzoquinone-Hydroquinone Couple for Flow Battery

At present, there is an ongoing search for approaches toward the storage of energy from intermittent renewable sources like wind and solar. Flow batteries have gained attention due to their potential viability for inexpensive storage of large amounts of energy. While the quinone/hydroquinone redox couple is a widely studied redox pair, its application in energy storage has not been widely explored. Because of its high reversibility, low toxicity, and low component costs, we propose the quinone/hydroquinone redox couple as a viable candidate for use in a grid-scale storage device. We have performed single-electrode tests on several quinone/hydroquinone redox couples, achieving current densities exceeding 500 mA/cm2, which is acceptable for use in energy applications. We fabricated a full cell using para-benzoquinone at the positive electrode against a commercial fuel cell hydrogen electrode separated by a Nafion membrane. We evaluated its performance in galvanic mode, where it reached current densities as high as 150 mA/cm2. The results from these studies indicate that the quinone/hydroquinone redox couple is a promising candidate for use in redox flow batteries.Physic

Hydrogel Microcapsules with Dynamic pH-Responsive Properties from Methacrylic Anhydride

Dynamic microcapsules are a highly sought-after class of encapsulant for advanced delivery applications with dynamically tunable release profiles, as actively manipulatable microreactors, or as selective microtraps for molecular separation and purification. Such dynamic microcapsules can only be realized with a nondestructive trigger-response mechanism that changes the permeability of the shell membrane reversibly, as found in hydrogels. However, the direct synthesis of a trigger-responsive hydrogel membrane around a water drop without the use of sacrificial templates remains elusive due to the incompatibility of the synthesis chemistry with aqueous emulsion processing. Here, we report on a facile approach to fabricate reversibly responsive hydrogel microcapsules utilizing reactive anhydride chemistry. Cross-linked and hydrophobic poly­(methacrylic anhydride) microcapsules are obtained from microfluidic double emulsion drop templating that enables direct encapsulation of hydrophilic, water-suspended cargo within the aqueous core. Hydrolysis in aqueous environment yields microcapsules with a poly­(acid) hydrogel shell that exhibit high mechanical and chemical stability for repeated cycling between its swollen and nonswollen states without rupture or fatigue. The permeability of the microcapsules is strongly dependent on the degree of swelling and hence can be actively and dynamically modified, enabling repeated capture, trap, and release of aqueous cargo over numerous cycles

Fluorocarbon Oil Reinforced Triple Emulsion Drops for Encapsulation and Retention of Small Molecules

2

Hydrogel Microcapsules with Dynamic pH-Responsive Properties from Methacrylic Anhydride

Dynamic microcapsules are a highly sought-after class of encapsulant for advanced delivery applications with dynamically tunable release profiles, as actively manipulatable microreactors, or as selective microtraps for molecular separation and purification. Such dynamic microcapsules can only be realized with a nondestructive trigger-response mechanism that changes the permeability of the shell membrane reversibly, as found in hydrogels. However, the direct synthesis of a trigger-responsive hydrogel membrane around a water drop without the use of sacrificial templates remains elusive due to the incompatibility of the synthesis chemistry with aqueous emulsion processing. Here, we report on a facile approach to fabricate reversibly responsive hydrogel microcapsules utilizing reactive anhydride chemistry. Cross-linked and hydrophobic poly­(methacrylic anhydride) microcapsules are obtained from microfluidic double emulsion drop templating that enables direct encapsulation of hydrophilic, water-suspended cargo within the aqueous core. Hydrolysis in aqueous environment yields microcapsules with a poly­(acid) hydrogel shell that exhibit high mechanical and chemical stability for repeated cycling between its swollen and nonswollen states without rupture or fatigue. The permeability of the microcapsules is strongly dependent on the degree of swelling and hence can be actively and dynamically modified, enabling repeated capture, trap, and release of aqueous cargo over numerous cycles

Hydrogel Microcapsules with Dynamic pH-Responsive Properties from Methacrylic Anhydride

Dynamic microcapsules are a highly sought-after class of encapsulant for advanced delivery applications with dynamically tunable release profiles, as actively manipulatable microreactors, or as selective microtraps for molecular separation and purification. Such dynamic microcapsules can only be realized with a nondestructive trigger-response mechanism that changes the permeability of the shell membrane reversibly, as found in hydrogels. However, the direct synthesis of a trigger-responsive hydrogel membrane around a water drop without the use of sacrificial templates remains elusive due to the incompatibility of the synthesis chemistry with aqueous emulsion processing. Here, we report on a facile approach to fabricate reversibly responsive hydrogel microcapsules utilizing reactive anhydride chemistry. Cross-linked and hydrophobic poly­(methacrylic anhydride) microcapsules are obtained from microfluidic double emulsion drop templating that enables direct encapsulation of hydrophilic, water-suspended cargo within the aqueous core. Hydrolysis in aqueous environment yields microcapsules with a poly­(acid) hydrogel shell that exhibit high mechanical and chemical stability for repeated cycling between its swollen and nonswollen states without rupture or fatigue. The permeability of the microcapsules is strongly dependent on the degree of swelling and hence can be actively and dynamically modified, enabling repeated capture, trap, and release of aqueous cargo over numerous cycles

Hydrogel Microcapsules with Dynamic pH-Responsive Properties from Methacrylic Anhydride

Dynamic microcapsules are a highly sought-after class of encapsulant for advanced delivery applications with dynamically tunable release profiles, as actively manipulatable microreactors, or as selective microtraps for molecular separation and purification. Such dynamic microcapsules can only be realized with a nondestructive trigger-response mechanism that changes the permeability of the shell membrane reversibly, as found in hydrogels. However, the direct synthesis of a trigger-responsive hydrogel membrane around a water drop without the use of sacrificial templates remains elusive due to the incompatibility of the synthesis chemistry with aqueous emulsion processing. Here, we report on a facile approach to fabricate reversibly responsive hydrogel microcapsules utilizing reactive anhydride chemistry. Cross-linked and hydrophobic poly­(methacrylic anhydride) microcapsules are obtained from microfluidic double emulsion drop templating that enables direct encapsulation of hydrophilic, water-suspended cargo within the aqueous core. Hydrolysis in aqueous environment yields microcapsules with a poly­(acid) hydrogel shell that exhibit high mechanical and chemical stability for repeated cycling between its swollen and nonswollen states without rupture or fatigue. The permeability of the microcapsules is strongly dependent on the degree of swelling and hence can be actively and dynamically modified, enabling repeated capture, trap, and release of aqueous cargo over numerous cycles

Fluorocarbon Oil Reinforced Triple Emulsion Drops

Fluorocarbon oil reinforced triple emulsion drops are prepared to encapsulate a broad range of polar and non-polar cargoes in a single platform. In addition, it is demonstrated that the fluorocarbon oil within the emulsion drop acts as an effective diffusion barrier, as well as a non-adhesive layer, enabling highly efficient encapsulation and retention of small molecules and active biomolecules in microcapsules.1111Nsciescopu

3D printed hollow microneedles for treating skin wrinkles using different anti-wrinkle agents: a possible futuristic approach

Skin wrinkles are an inevitable phenomenon that is brought about by aging due to the degradation of scleroprotein fibers and significant collagen reduction, which is the fundamental basis of anti-wrinkle technology in use today. Conventional treatments such as lasering and Botulinum toxin have some drawbacks including allergic skin reactions, cumbersome treatment procedures, and inefficient penetration of the anti-wrinkle products into the skin due to the high resistance of stratum corneum. Bearing this in mind, the cosmetic industry has exploited the patient-compliant technology of microneedles (MNs) to treat skin wrinkles, developing several products based on solid and dissolvable MNs incorporated with antiwrinkle formulations. However, drug administration via these MNs is limited by the high molecular weight of the drugs. Hollow MNs (HMNs) can deliver a wider array of active agents, but that is a relatively unexplored area in the context of antiwrinkle technology. To address this gap, we discuss the possibility of bioinspired 3D printed HMNs in treating skin wrinkles in this paper. We compare the previous and current anti-wrinkling treatment options, as well as the techniques and challenges involved with its manufacture and commercialization.</p