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Track II: Transportation and Biofuels ; Includes audio file (18 min.) ; A novel, robust, fuel reformation technology has been developed for portable, mobile, stationary, and on-site generation of hydrogen from a variety of feedstocks involving both renewable and nonrenewable resources. Unlike conventional steam methane reforming (SMR), this novel reforming process is carried out non-catalytically in supercritical water, where supercritical water acts both as a highly-energized reforming agent and as an extraordinary homogenizing solvent. The unparalleled merits of this technology, as demonstrated in an experimental prototype system, are quite numerous, including: (a) catalyst-free reactions; (b) capability of handling high sulfur-containing liquid fuels; (c) high once-through conversion; (d) lower temperature operation and higher energy efficiency than conventional steam reforming technology; (e) alleviation and control of coking; (f) use of unpurified, locally available water; (g) compact size and minimal space requirements; (h) great flexibility in feedstock variety; and (h) near-zero discharge. The process technology is superbly applicable to the U.S. military's need for mobile electric power (MEP) generation based on integrated fuel reformation-fuel cell systems, for purposes of stealth (reduced noise and thermal signature), increased mission endurance (higher efficiency), and reduced logistical burden (overall lower fuel consumption). The process technology is also eminently suitable for on-site hydrogen generation via energy-efficient conversion of ethanol crude beer into hydrogen, thus providing a means of seamless integration between the Hydrogen Economy and the Ethanol Economy. Scientific and technological details of the supercritical water reformation (SWR) process will be discussed, with a particular emphasis placed on process chemistry, process engineering, energy materials, and prototype design.

An economically viable and environmental friendly method of generating hydrogen for fuel cells is by the reaction of certain metals with steam, called metalsteam reforming (MSR). This technique does not generate any toxic by-products nor contributes to the undesirable greenhouse effect. From the standpoint of favorable thermodynamics, total environmental benignity, and attractive economics, iron appears to be the metal of choice for such a process. An inexpensive source of iron for the MSR is the steel industry's mill-scale waste via hydrogen and carbothermic reduction, both of which are energy-intensive processes. These have been eliminated by a novel, solution-based room temperature technique producing nanoscale iron, thus obviating the sintering of iron or iron oxide and deactivation during the cyclic operation of MSR. Some preliminary results are presented of an investigation aimed at converting the mill-scale waste into nanoscale iron, which was subsequently used in generating hydrogen for proton exchange membrane fuel cells.

AbstractGreen hydrogen generation technologies are currently the most pressing worldwide issues, offering promising alternatives to existing fossil fuels that endanger the globe with growing global warming. The current research focuses on the creation of green hydrogen in alkaline electrolytes utilizing a Ni-Co-nano-graphene thin film cathode with a low overvoltage. The recommended conditions for creating the target cathode were studied by electrodepositing a thin Ni-Co-nano-graphene film in a glycinate bath over an iron surface coated with a thin copper interlayer. Using a scanning electron microscope (SEM) and energy-dispersive X-ray (EDX) mapping analysis, the obtained electrode is physically and chemically characterized. These tests confirm that Ni, Co, and nano-graphene are homogeneously dispersed, resulting in a lower electrolysis voltage in green hydrogen generation. Tafel plots obtained to analyze electrode stability revealed that the Ni-Co-nano-graphene cathode was directed to the noble direction, with the lowest corrosion rate. The Ni-Co-nano-graphene generated was used to generate green hydrogen in a 25% KOH solution. For the production of 1 kg of green hydrogen utilizing Ni-Co-nano-graphene electrode, the electrolysis efficiency was 95.6% with a power consumption of 52 kwt h−1, whereas it was 56.212. kwt h−1 for pure nickel thin film cathode and 54. kwt h−1 for nickel cobalt thin film cathode, respectively.

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record ; To tackle the energy crisis and achieve a more sustainable development, hydrogen as a clean and renewable energy resource has attracted great interest. Searching for cheap but efficient catalysts for hydrogen production from water splitting is urgently needed. In this report, bimetallic Fe-Mo sulfide/carbon nanocomposites that derived from a polyoxometalate phosphomolybdic acid encapsulated in metal organic framework MIL-100 (PMA@MIL-100) have been generated and their applications in electrocatalytic hydrogen generation were explored. The PMA@MIL-100 precursor is formed via a simple one-pot hydrothermal synthesis method and the bimetallic Fe-Mo sulfide/carbon nanocomposites were obtained by chemical vapour sulfurization of PMA@MIL-100 at high temperatures. The nanocomposite samples were fully characterized by a series of techniques including XRD, FT-IR, TGA, N2 gas sorption, SEM, TEM, XPS, and were further investigated as electrocatalysts for hydrogen production from water splitting. The hydrogen production activity of the best performed bimetallic Fe-Mo sulfide/carbon nanocomposite exhibits an overpotential of -0.321 V at 10 mA cm-2 and a Tafel slope of 62 mV dec-1 with a 53% reduction in overpotential compared to Mo-free counterpart composite. This dramatic improvement in catalytic performance of the FeMo sulfide/carbon composite is attributed to the homogeneous distribution of the nanosized iron sulfide, MoS2 particles and the formation Fe-Mo-S phases in the S-doped porous carbon matrix. This work has demonstrated a potential approach to fabricate complex heterogeneous catalytic materials for different applications. ; Engineering and Physical Sciences Research Council (EPSRC) ; Leverhulme Trust ; European Union

The interaction strength of Au nanoparticles with pristine and nitrogen doped TiO2 nanowire surfaces was analysed using density functional theory and their significance in enhancing the solar driven photoelectrocatalytic properties was elucidated. In this article, we prepared 4-dimethylaminopyridine capped Au nanoparticle decorated TiO2 nanowire systems. The density functional theory calculations show {101} facets of TiO2 as the preferred phase for dimethylaminopyridine–Au nanoparticles anchoring with a binding energy of 8.282 kcal mol1 . Besides, the interaction strength of Au nanoparticles was enhanced nearly four-fold (35.559 kcal mol1 ) at {101} facets via nitrogen doping, which indeed amplified the Au nanoparticle density on nitrided TiO2. The Au coated nitrogen doped TiO2 (N–TiO2–Au) hybrid electrodes show higher absorbance owing to the light scattering effect of Au nanoparticles. In addition, N–TiO2–Au hybrid electrodes block the charge leakage from the electrode to the electrolyte and thus reduce the charge recombination at the electrode/electrolyte interface. Despite the beneficial band narrowing effect of nitrogen in TiO2 on the electrochemical and visible light activity in N–TiO2–Au hybrid electrodes, it results in low photocurrent generation at higher Au NP loading (3.4 107 M) due to light blocking the N–TiO2 surface. Strikingly, even with a ten-fold lower Au NP loading (0.34 107 M), the synergistic effects of nitrogen doping and Au NPs on the N–TiO2–Au hybrid system yield high photocurrent compared to TiO2 and TiO2–Au electrodes. As a result, the N–TiO2–Au electrode produces nearly 270 mmol h1 cm2 hydrogen, which is nearly two-fold higher than the pristine TiO2 counterpart. The implications of these findings for the design of efficient hybrid photoelectrocatalytic electrodes are discussed. Introduc ; Global Research Laboratory (GRL) Program through the National Research Foundation of Korea (NRF) - Ministry of Science. K20704000003TA050000310 Japan Society for the Promotion of Science (JSPS) University Jaume I. P1.1B2014-51 Government of the Russian Federation. 074-U01

This paper presents, the numerical analysis of heat and mass transfer during hydrogen generation in an array of fuel cylinder bars, each coated with a cladding and a steam current flowing outside the cylinders. The analysis considers the fuel element without mitigation effects. The system consists of a representative periodic unit cell where the initial and boundary-value problems for heat and mass transfer were solved. In this unit cell, we considered that a fuel element is coated by a cladding with steam surrounding it as a coolant. The numerical simulations allow describing the evolution of the temperature and concentration profiles inside the nuclear reactor and could be used as a basis for hybrid upscaling simulations.