Abstract: The ready availability and cheapness of azo compounds have increased their use as intermediary products in organic synthesis. In addition, they are widely applied in dye and pharmaceutical industries. However, they have been found to be toxic and in some cases mutagenic. Due to the large degree of aromatics present in azo dye molecules and their biologicalpersistence, conventional biological and physical methods areineffective for their discoloration, degradation, or removal.Electrochemical methods, such as electrocoagulation (EC), have been used in recent times for the most effective removal of orange II azo dye from wastewaters using iron, aluminum and combination of them as electrodes. Photo-oxidative methods might be another option for the photo-degradation of azo dyes. In this paper, we present our results on EC and photo-oxidative treatment of orange II azo dye. A cyclic voltammetric study on it was performed followed by a discussion on mechanisms of these processes.

Abstract: Electrocoagulation (EC) has been known for more than a century. Applications in industries as a water and wastewater treatment process have been adapted for the removal of metals, non metals, suspended solids, organic compounds, COD and BOD. Iron electrodes have been preferred over aluminum due to their durability and cost. However, the electrochemical reactions occurring with EC using iron electrodes have not been systematically studied. For a better understanding of the mechanism and reactions for EC using iron electrodes, we present a review of the concept of green rust (GR) and its relationship to the current theory of EC. Experimental results obtained by measuring pH at different zones near the iron electrodes during the EC process are detailed, and are used to illustrate the mechanism and reactions that occur at both, the anode and cathode. Mechanism and reactions presented explain phenomena associated with EC and are congruent with solubility and Pourbaix diagrams.

Abstract: Green rusts are unstable compounds containing a mixture of ferrous and ferric hydroxides that belong to a family of minerals known as layered double hydroxides (LDH). They can be represented with the general formula [FeII(6-x) FeIIIx (OH)12] x+[Ax/n-*yH2O] x-, where A is an n-valent anion mainly Cl-, CO3-2 and SO4-2, and in which either the bivalent or the trivalent iron can be replaced for other trivalent or bivalent metal ions. Green rust was first identified and studied as a corrosion product later it was identified in soils and related to interactions between microbes and metals in soils. Green rusts have been shown to be highly reactive compounds that are useful in the reduction of organic compounds such as methachlor, of inorganic elements such as Chromium, Selenium and Uranium; Arsenic removal, and in the treatment of Acid mine drainage (AMD). Green rust has been synthesized combining Fe(II) and Fe(III), by air oxidation of FeCl2 and other methods. In this paper, the electrochemical generation of green rust, its characterization by X-ray Diffraction (XRD), and implications to electrocoagulation will be discussed

Abstract: HydroGEN (https://www.h2awsm.org/) Energy Materials Network (EMN) a Fuel Cell Technologies Office (FCTO) consortium that aims to accelerate the discovery and development of advanced water splitting materials (AWSM) for sustainable, large-scale hydrogen production, and to more effectively enable the widespread commercialization of hydrogen and fuel cell technologies, in line with the H2@Scale initiative (https://www.energy.gov/eere/fuelcells/h2-scale), and meet the ultimate cost target for production set by the U.S. Department of Energy (DOE) at $2/kg H 2 . HydroGEN EMN is a six national laboratories consortium comprises National Renewable Energy Laboratory (NREL) - lead, Lawrence Berkeley National Laboratory (LBNL), Sandia National Laboratory (SNL), Lawrence Livermore National Laboratory (LLNL), Idaho National Laboratory (INL), and Savannah River National Laboratory (SRNL). With the rollouts of fuel cell electric vehicles (FCEVs) by major automotive manufacturers underway, enabling AWS technologies for the widespread production of affordable, sustainable hydrogen becomes increasingly important. The HydroGEN Consortium offers more than 80 materials capabilities nodes to help address RD & D challenges in efficiency, durability and cost. The capabilities span computational tools and modeling, materials synthesis, characterization, process manufacturing and scale-up, and analysis. Detailed descriptions of all the HydroGEN nodes are available in a searchable format on the HydrogGEN website (https://www.h2awsm.org/capabilities), including information such as the host National Lab, the capability experts, and a synopsis of the node’s unique aspects and capability bounds. By design, the nodes are cross-cutting, and any given node may be useful for one or several advanced water splitting (AWS) technologies. Leveraging the HydroGEN consortium’s staff of technical experts and broad collection of resource capabilities is expected to advance the maturity and technology readiness levels in all the AWS technologies, including low- and high-temperature electrolysis, photoelectrochecmical (PEC) and solar thermochemical (STCH) routes, which includes hybridized thermochemical and electrolysis approaches to water splitting. Currently, there are 20 HydroGEN seedling projects, and one project focused on benchmarking advanced water splitting technologies. These 21 new projects utilized over 40 unique capabilities across the six HydroGEN core labs. HydroGEN is indeed a national innovation ecosystem that comprises 11 national labs, 7 companies, and 30 universities. The experimental and computational data generated within HydroGEN are stored and shared within and across projects within the secured HydroGEN Data Hub (https://datahub.h2awsm.org/), which currently comprises 128 users and 3889 data files. The goal is to make the digital data generated within HydroGEN accessible, so the data can be shared and leveraged throughout the EMNs and in future programs. This presentation will provide an overview of the HydroGEN EMN consortium and highlight some low temperature water electrolysis projects. Proton Onsite met and exceeded near-term performance targets of 1.85V (achieved 1.8 V) at 2.0 A/cm 2 , using Proton-synthesized high activity IrRu oxide catalysts of different compositions. The Proton PEM water electrolysis cell also demonstrated 800 hours of durability at 2 A/cm 2 , operating at 80°C and 30 bar. This project utilized NREL’s ex-situ characterization node towards a better understanding of IrRu oxide catalysts stability. Proton’s improved cell efficiency is a step towards achieving its PEM water electrolysis cell efficiency goal of 43 kWh/kg (1.7 V at 90°C) and at a cost of $2/kg H 2 . Collaboratively, LANL, SNL, and NREL demonstrated promising alkaline exchange membrane water electrolysis performance, comparable to iridium oxide, using SNL Anion Exchange Membrane node, LANL-developed PGM-free oxygen evolution reaction perovskite catalyst, and NREL’s expertise in membrane electrode assembly fabrication (Multicomponent Ink Development, High-Throughput Fabrication, and Scaling Studies node) and cell electrolysis testing (In-Situ Testing Capabilities for Hydrogen Generation node). ANL, together with the LLNL Ab Initio Modeling of Electrochemical Interfaces and LBNL Density Functional Theory and Ab Initio Calculations nodes, investigated the factors that may alter the transport property of a cobalt-based oxygen evolution reaction catalyst, developed by ANL for proton exchange membrane electrolysis. The LLNL team found the origin of the discrepancy between the reported experimental and theory-derived electronic structure of cobalt oxide. This resulted in the confidence to choose a specific theory that can provide reliable information about the electronic structure of the cobalt oxide materials family. This is crucial to reliably identify the factors that determine the transport property of this material, which affects the overall catalytic activity. HydroGEN looks forward to growing its membership of industry, university and laboratory collaborators that can partner with member-laboratory experts by way of CRADAs and potential future FOAs. Moving forward, HydroGEN will expand its presence in the AWS community through working group meetings and participation at relevant professional meetings.

Abstract: The U.S. Department of Energy is supporting the research, development, and deployment of all types of fuel cells for transportation, material handling, portable power, back-up power, stationary power, and combined heat and power applications. A major focus of this support is polymer electrolyte membrane fuel cells. Key issues inhibiting their widespread penetration and commercialization of fuel cells are performance, durability, and cost and a key component is electrode technology including supports and catalysts. The approaches to improvement in electrode technology include alloys, core/shell structures, thin continuous catalyst films, non-precious metal catalysts, and alternative supports. Major progress has been realized recently. This paper provides an overview of DOE-funded advances and status.

Abstract: Harnessing the power of the sun to produce energy-rich chemicals from abundant resources offers the promise of providing a plentiful supply of sustainable solar fuels to meet future U.S. energy needs. Opportunities for producing strategically-important solar fuels include hydrogen from water, hydrocarbon fuels from carbon dioxide and hydrogen/water, and ammonia from di-nitrogen and hydrogen/water. Most fuels are currently produced from fossil resources using energy-intense high temperature processes, but advanced processes for fuel synthesis utilizing sunlight in conjunction with air and water can provide critical supplements to help meet near- and longer-term energy demands. Most pathways for solar fuels rely heavily on the availability of an abundant and sustainable hydrogen supply. More generally, synthetic fuels production is an important end-use sector supported by the U.S. Department of Energy’s (DOE) H2@scale initiative. Specific challenges and opportunities for a new generation of solar fuels production will be discussed in the context of H2@Scale as well as other DOE efforts including the Fuels from Sunlight Energy Innovation Hub and the HydroGEN Energy Materials Network Consortium on Advanced Water Splitting Materials.

Abstract: Accelerating the discovery and development of novel materials is essential for the U.S. to compete globally in key energy sectors throughout the 21st century and beyond. In support of its priorities in energy-materials innovation, the U.S. Department of Energy (DOE) established the Energy Materials Network (EMN) as a network of application-specific consortia that facilitate industry and academia access to the unique and world-class resources at the national laboratories in materials theory, computation, experimentation, analysis, and data informatics. EMN consortia have been established to address a broad range of materials challenges in specific energy-related applications such as platinum-group-free catalysts for fuel cells, advanced water-splitting materials, breakthrough materials for hydrogen storage materials and carriers, next-generation catalysts for bio-fuels and products, light-weight materials to revolutionize the transportation sector, and new module materials to support and enable the large-scale deployment of photovoltaics. The EMN model along with recent scientific accomplishments from individual EMN consortia will be discussed.

Abstract: The U.S. Department of Energy (DOE) is supporting a wide range of research and development efforts that fall under the umbrella of low temperature electrolysis (LTE). These efforts range from early stage R & D on cell components to demonstrating the effectiveness of integrating MW-scale electrolyzer systems with the electric grid to provide ancillary services. LTE is included in multiple initiatives led by the Fuel Cell Technologies Office (FCTO) at DOE’s Office of Energy Efficiency and Renewable Energy (EERE). Low temperature electrolysis is one of four pathways being supported under DOE’s HydroGEN Energy Materials Network (EMN) Consortium on Advanced Water Splitting Materials (AWSM) for H 2 production. The HydroGEN EMN offers an extensive collection of materials research capabilities at 6 core national laboratories for addressing AWSM R & D challenges in efficiency, durability, and cost. The LTE work supported under HydroGEN includes early stage R & D in membranes and catalysts for both PEM and AEM electrolysis. Low temperature electrolysis also has a role in DOE’s H2@Scale energy system vision. This initiative is bringing together diverse stakeholders to advance affordable wide-scale hydrogen production, transport, storage, and utilization to unlock revenue potential and value across multiple sectors. The use of low-cost electricity to affordably split water into hydrogen and oxygen is central to implementation of the H2@Scale concept. Work is also being carried out on electrolyzer manufacturing, benchmarking, protocol development, and technoeconomic analysis. An overview of FCTO-supported activities related to these initiatives and topics, and the role of LTE in them, will be provided.