Self-sustainable protonic ceramic electrochemical cells using a triple conducting electrode for hydrogen and power production.

The protonic ceramic electrochemical cell (PCEC) is an emerging and attractive technology that converts energy between power and hydrogen using solid oxide proton conductors at intermediate temperatures. To achieve efficient electrochemical hydrogen and power production with stable operation, highly robust and durable electrodes are urgently desired to facilitate water oxidation and oxygen reduction reactions, which are the critical steps for both electrolysis and fuel cell operation, especially at reduced temperatures. In this study, a triple conducting oxide of PrNi0.5Co0.5O3-δ perovskite is developed as an oxygen electrode, presenting superior electrochemical performance at 400~600 °C. More importantly, the self-sustainable and reversible operation is successfully demonstrated by converting the generated hydrogen in electrolysis mode to electricity without any hydrogen addition. The excellent electrocatalytic activity is attributed to the considerable proton conduction, as confirmed by hydrogen permeation experiment, remarkable hydration behavior and computations

Suppression of MAPK11 or HIPK3 reduces mutant Huntingtin levels in Huntington's disease models.

Most neurodegenerative disorders are associated with accumulation of disease-relevant proteins. Among them, Huntington disease (HD) is of particular interest because of its monogenetic nature. HD is mainly caused by cytotoxicity of the defective protein encoded by the mutant Huntingtin gene (HTT). Thus, lowering mutant HTT protein (mHTT) levels would be a promising treatment strategy for HD. Here we report two kinases HIPK3 and MAPK11 as positive modulators of mHTT levels both in cells and in vivo. Both kinases regulate mHTT via their kinase activities, suggesting that inhibiting these kinases may have therapeutic values. Interestingly, their effects on HTT levels are mHTT-dependent, providing a feedback mechanism in which mHTT enhances its own level thus contributing to mHTT accumulation and disease progression. Importantly, knockout of MAPK11 significantly rescues disease-relevant behavioral phenotypes in a knockin HD mouse model. Collectively, our data reveal new therapeutic entry points for HD and target-discovery approaches for similar diseases

Design, Synthesis, and Characterization of Nanostructured Catalysts for Clean Energy and Environmental Applications

This thesis contains three parts: 1) electrocatalytic reduction of CO 2, 2) synthesis of useful compounds from CO2 by Fischer-Tropch synthesis, and 3) doped octahedral molecular sieve manganese oxides with enhanced catalytic activity. Heterogeneous (electro)catalytic conversion of carbon dioxide is one of the viable solutions to reduce greenhouse gas emission and simultaneous production of useful compounds. In the first part, a proof-of-concept experiment has demonstrated that CO2, water, and renewable electricity could be used for the production of transportation fuels. Nano-sized platinum has been deposited on calcia-stabilized zirconia by metal organic chemical vapor deposition. The activation of CO2 was realized by polarizing metal/metal oxide interfaces with a DC voltage or current at 600-900°C. Cryptomelane-type octahedral molecule sieve manganese oxides (K-OMS-2) exhibited excellent conductivity and some activity at a low temperature of 350°C. Real time electrochemical impedance spectra (EIS) have shown the effects of polarization. The products were analyzed by gas chromatograph, nuclear magnetic resonance (NMR) spectroscopy, and liquid chromatography–mass spectrometry (LC-MS). The high selectivity to paraformaldehyde was achieved as high as 100% and CO2 conversion was 8-33%. Ethylene and methanol were also produced using other low cost ZnO, Fe, SiC, and Co catalysts. ^ In the second part, Fe and Co catalysts supported on K-OMS-2 have proven to be efficient Fischer-Tropsch catalysts for CO2 hydrogenation with 45% CO2 conversion and for CO hydrogenation with 87% CO conversion. Valuable light olefins, carboxylic acids, jet fuel, and α-hydroxylic acids have been selectively produced under different conditions. The synergistic effects of metal carbides, potassium, and manganese oxides contribute to a high activity and selectivity. A new mechanism has been developed based on experimental data. ^ In the third part, Cu2+, CO3+, and Ce 4+ doped porous K-OMS-2 have been synthesized using one-step hydrothermal methods. Doped K-OMS-2 has shown higher catalytic activities in phenol oxidation, oxidation of tetralol, and microbial fuel cells compared with undoped K-OMS-2. This study demonstrated that increase in defects (edge dislocations and oxygen vacancies) results in enhanced catalytic reactions. The controllable edge dislocations in doped K-OMS-2 nanofibers were shown in high-resolution transmission electron microscopy (HRTEM) images.

Design, Synthesis, and Characterization of Nanostructured Catalysts for Clean Energy and Environmental Applications

This thesis contains three parts: 1) electrocatalytic reduction of CO 2, 2) synthesis of useful compounds from CO2 by Fischer-Tropch synthesis, and 3) doped octahedral molecular sieve manganese oxides with enhanced catalytic activity. Heterogeneous (electro)catalytic conversion of carbon dioxide is one of the viable solutions to reduce greenhouse gas emission and simultaneous production of useful compounds. In the first part, a proof-of-concept experiment has demonstrated that CO2, water, and renewable electricity could be used for the production of transportation fuels. Nano-sized platinum has been deposited on calcia-stabilized zirconia by metal organic chemical vapor deposition. The activation of CO2 was realized by polarizing metal/metal oxide interfaces with a DC voltage or current at 600-900°C. Cryptomelane-type octahedral molecule sieve manganese oxides (K-OMS-2) exhibited excellent conductivity and some activity at a low temperature of 350°C. Real time electrochemical impedance spectra (EIS) have shown the effects of polarization. The products were analyzed by gas chromatograph, nuclear magnetic resonance (NMR) spectroscopy, and liquid chromatography–mass spectrometry (LC-MS). The high selectivity to paraformaldehyde was achieved as high as 100% and CO2 conversion was 8-33%. Ethylene and methanol were also produced using other low cost ZnO, Fe, SiC, and Co catalysts. ^ In the second part, Fe and Co catalysts supported on K-OMS-2 have proven to be efficient Fischer-Tropsch catalysts for CO2 hydrogenation with 45% CO2 conversion and for CO hydrogenation with 87% CO conversion. Valuable light olefins, carboxylic acids, jet fuel, and α-hydroxylic acids have been selectively produced under different conditions. The synergistic effects of metal carbides, potassium, and manganese oxides contribute to a high activity and selectivity. A new mechanism has been developed based on experimental data. ^ In the third part, Cu2+, CO3+, and Ce 4+ doped porous K-OMS-2 have been synthesized using one-step hydrothermal methods. Doped K-OMS-2 has shown higher catalytic activities in phenol oxidation, oxidation of tetralol, and microbial fuel cells compared with undoped K-OMS-2. This study demonstrated that increase in defects (edge dislocations and oxygen vacancies) results in enhanced catalytic reactions. The controllable edge dislocations in doped K-OMS-2 nanofibers were shown in high-resolution transmission electron microscopy (HRTEM) images.

Enhanced Long Term Durability of Metal-Supported Solid Oxide Electrolysis Cells By Advanced Coatings

Metal-supported solid oxide electrolysis cells (MS-SOECs) with symmetric cell architecture were developed for high temperature electrolysis at Lawrence Berkeley National Laboratory (LBNL). The cell is comprised of a thin ceramic electrolyte and porous electrode backbones sandwiched between stainless steel metal supports. MS-SOECs offer a number of advantages over conventional all-ceramic SOECs due to their low-cost structural materials (e.g. stainless steel), mechanical ruggedness, excellent tolerance to redox cycling, and extremely fast start-up capability. The current density of MS-SOEC at 1.3 V and 50 vol% steam content is improved by optimizing microstructure of electrode backbone and procedure of catalyst infiltration. MS-SOEC with composite LSCF-SDC air electrode catalyst displays a degradation rate of 1.6%/100 h with current density of 0.33 A cm-2 at 700 °C in 1000 h test (Figure 1). Post-mortem analysis reveals that the degradation is caused by the primary modes of fuel electrode catalyst coarsening and Cr poisoning on air electrode catalyst, and secondary modes of metal support oxidation and local elemental accumulation of Ni. In an effort to suppress Cr migration thereby improving long term durability, advanced coatings, such as CoOx, NiFe2O4, (Co,Mn)3O4, etc., are applied to the cathode-side support by atomic layer deposition or electrodeposition. The impact of coating composition and deposition method will be reported. Figure 1. Durability of the cell with LSCF-SDC air electrode catalysts at constant current of 0.33 A cm-2 and 700 °C, with 50 vol% H2-50 vol% H2O. Figure