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(CO2)2N2O is Cyanogen Chloride-like structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of four carbon dioxide molecules and two hydroxylamine, o-amino- molecules.
(C)4CO(CCl)14CCl4 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two carbon tetrachloride molecules, twenty-eight chloromethane molecules, two formaldehyde molecules, and eight methane molecules.
NNCuCO(CO2)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four carbon dioxide molecules and two NNCuCO clusters. In each NNCuCO cluster, Cu2+ is bonded in a distorted single-bond geometry to one O2- atom. The Cu–O bond length is 2.02 Å. C4+ is bonded in a 1-coordinate geometry to two N2- and one O2- atom. Both C–N bond lengths are 1.36 Å. The C–O bond length is 1.23 Å. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a distorted single-bond geometry to one C4+ atom. In the second N2- site, N2- is bonded in a 1-coordinate geometry to one C4+ atom. O2- is bonded in a bent 120 degrees geometry to one Cu2+ and one C4+ atom.
Ti2OCl6CO2(HSeOCl2)2(SeCl)2(Cl2)2 crystallizes in the monoclinic P2/c space group. The structure is zero-dimensional and consists of two carbon dioxide molecules, four chlorine molecules, four chloroselenurane molecules, two HSeOCl2 clusters, and two Ti2OCl6 clusters. In each HSeOCl2 cluster, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. Se3+ is bonded in a distorted L-shaped geometry to one O2- and one Cl1- atom. The Se–O bond length is 1.81 Å. The Se–Cl bond length is 2.39 Å. O2- is bonded in a distorted water-like geometry to one H1+ and one Se3+ atom. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted linear geometry to two Cl1- atoms. There are one shorter (2.08 Å) and one longer (2.92 Å) Cl–Cl bond lengths. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Se3+ and one Cl1- atom. In each Ti2OCl6 cluster, Ti4+ is bonded to one O2- and three Cl1- atoms to form corner-sharing TiCl3O tetrahedra. The Ti–O bond length is 1.79 Å. There are two shorter (2.19 Å) and one longer (2.21 Å) Ti–Cl bond lengths. O2- is bonded in a linear geometry to two equivalent Ti4+ atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ti4+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ti4+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ti4+ atom.
MnO2(CO2)2 is Cyanogen Chloride-like structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight carbon dioxide molecules and four manganese hydroxide (mn(oh)2) molecules.
Fe(CO3)2 crystallizes in the orthorhombic Cccm space group. The structure is zero-dimensional and consists of sixteen carbon dioxide molecules and eight iron dihydroxide molecules.
CO2 is Cyanogen Chloride-derived structured and crystallizes in the orthorhombic Cmce space group. The structure is zero-dimensional and consists of four carbon dioxide molecules. C4+ is bonded in a linear geometry to two equivalent O2- atoms. Both C–O bond lengths are 1.17 Å. O2- is bonded in a single-bond geometry to one C4+ atom.
CuO2(N2CO)2(CO2)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four carbon dioxide molecules, two copper(ii) hydroxide molecules, and four N2CO clusters. In each N2CO cluster, C4+ is bonded in a 1-coordinate geometry to two N+0.50- and one O2- atom. Both C–N bond lengths are 1.40 Å. The C–O bond length is 1.20 Å. There are two inequivalent N+0.50- sites. In the first N+0.50- site, N+0.50- is bonded in a 1-coordinate geometry to one C4+ and one N+0.50- atom. The N–N bond length is 1.32 Å. In the second N+0.50- site, N+0.50- is bonded in a 1-coordinate geometry to one C4+ and one N+0.50- atom. O2- is bonded in a single-bond geometry to one C4+ atom.
Interconverting electrical and chemical energy efficiently and cost-effectively provides a massive opportunity to generate renewable hydrogen, create net-zero fuels and chemicals, capture and convert carbon dioxide (CO2), and create innovative sustainable industrial processes.
This presentation is being submitted as part of a sponsored session titled, "The Role of Carbon Capture & Storage in Reaching Net Zero Emissions," to the United States Association for Energy Economics (USAEE) and will be presented at the 39th USAEE/International Association for Energy Economics (IAEE) North American Conference to be held October 24–26, 2022, in Houston, Texas.
The shipping industry contributes to a substantial quantity of global carbon emissions. Reaching a “Net-Zero World” will ultimately require complete decarbonization of the existing fleet. Nuclear energy may provide a viable solution toward this end goal. To better understand the economic dynamics of relying on nuclear energy to power maritime fleets, cost targets were identified in this study. Two use cases were considered: (1) nuclear energy is used to generate synthetic fuel (termed synfuel) to power maritime propulsion, and (2) nuclear reactors for vessel propulsion. The study found that in both cases realistic cost targets for nuclear reactor costs could be reached. However, option 2 was deemed to be much more competitive overall but with higher technical risks.
M Gidden conducted this work prior to joining PNNL and no DOE OFFICE OF SCIENCE, OTHER DOE, OTHER FEDERAL, OR PNNL OVERHEAD FUNDING is being used. Stabilizing and then drawing down global temperature requires achieving net-negative CO2 emissions globally. Carbon removal is needed to offset “hard-to-abate” sectors that remain sources of emissions at net-zero and beyond. We argue the use of scarce carbon removal resources should be guided by the principles enshrined in the Paris Agreement.
The electrochemical reduction of carbon dioxide (CO 2 ) to ethylene presents a promising route for utilizing exhaust gases to produce value-added chemicals with broad manufacturing applications. While zero-gap electrolyzer architectures show great potential to enable commercial-scale CO 2 -to-ethylene conversion, their performance is often limited by failure within the first 100 hours. In this work, we demonstrate that a low-frequency electrochemical pulsing protocol effectively mitigates carbonate salt precipitation and flooding by managing water transport to and through the cathode gas diffusion electrode and associated flow fields. Operando neutron imaging further reveals the dynamics of water crossover and flooding, emphasizing the intricate interplay between electrochemical operation and ionic transport. By mitigating short-term flooding and salt precipitation failure modes, this study establishes a foundation for understanding long-term degradation mechanisms and advancing the practical viability of CO 2 electrolyzers for industrial-scale applications.
At Lawrence Livermore National Laboratory, we focus on science and technology research to ensure our nation’s security. We also apply that expertise to solve other important national problems in energy, bioscience, and the environment. Science & Technology Review is published eight times a year to communicate, to a broad audience, the Laboratory’s scientific and technological accomplishments in fulfilling its primary missions. The publication’s goal is to help readers understand these accomplishments and appreciate their value to the individual citizen, the nation, and the world. Achieving carbon neutrality requires a well-considered combination of technologies, private involvement, and public policies. As described in the article beginning on p. 4, Lawrence Livermore National Laboratory developed the Getting to Neutral: Options for Negative Carbon Emissions in California report, a three-pillared approach to bridge the gap between California’s initial plans to reduce carbon emissions and the state’s goal to achieve net zero emissions by 2045. The cover image represents the network of strategies and stakeholders involved in achieving carbon neutrality for the environment.
Currently responsible for over one fifth of carbon emissions worldwide, the transportation sector will need to undergo a substantial technological transition to ensure compatibility with global climate goals. Few studies have modeled strategies to achieve zero emissions across all transportation modes, including aviation and shipping, alongside an integrated analysis of feedbacks on other sectors and environmental systems. Here, we use a global integrated assessment model to evaluate deep decarbonization scenarios for the transportation sector consistent with maintaining end-of-century warming below 1.5 °C, considering varied timelines for fossil fuel phase-out and implementation of advanced alternative technologies. We highlight the leading low carbon technologies for each transportation mode, finding that electrification contributes most to decarbonization across the sector. Biofuels and hydrogen are particularly important for aviation and shipping. Our most ambitious scenario eliminates transportation emissions by mid-century, contributing substantially to achieving climate targets but requiring rapid technological shifts with integrated impacts on fuel demands and availability and upstream energy transitions.
Micro-tomography (μCT) and nuclear magnetic resonance (NMR) have been used to characterize porous media for decades. Here, Magnetic Resonance Imaging (MRI) enables direct visualization of pore architecture and many pulse sequences exist. In this work, we tested the MRI pulse sequence Zero Echo Time (ZTE) to study sandstone and carbonate for its ability to address short relaxation times. We aimed at resolving two fluid conduit scales, i.e. pores and fractures. In this research, we study tighter porous systems than those previously reported using ZTE. Additionally, Pore Cluster Analysis (PCA), combined with ZTE, can be used to analyze pore-fracture connectivity of relatively large core plugs. We show that ZTE can resolve two-scale pore systems simultaneously, i.e. fractures and pores. By combining Time-Domain NMR pore-size analysis and PCA, we show that careful selection of resolution is necessary to understand transport in porous media.
With companies, states, and countries targeting net-zero emissions around midcentury, there are questions about how these targets alter household welfare and finances, including distributional effects across income groups. This paper examines the distributional dimensions of technology transitions and net-zero policies with a focus on welfare impacts across household incomes. The analysis uses a model intercomparison with a range of energy-economy models using harmonized policy scenarios reaching economy-wide, net-zero CO 2 emissions across the United States in 2050. Here we employ a novel linking approach that connects output from detailed energy system models with survey microdata on energy expenditures across income classes to provide distributional analysis of net-zero policies. Although there are differences in model structure and input assumptions, we find broad agreement in qualitative trends in policy incidence and energy burdens across income groups. Models generally agree that direct energy expenditures for many households will likely decline over time with reference and net-zero policies. However, there is variation in the extent of changes relative to current levels, energy burdens relative to reference levels, and electricity expenditures. Policy design, primarily how climate policy revenues are used, has first-order impacts on distributional outcomes. Net-zero policy costs, in both absolute and relative terms, are unevenly distributed across households, and relative increases in energy expenditures are higher for lowest-income households. However, we also find that recycled revenues from climate policies have countervailing effects when rebated on a per-capita basis, offsetting higher energy burdens and potentially even leading to net progressive outcomes. Model results also show carbon Laffer curves, where revenues from net-zero policies increase but then decline with higher stringencies, which can diminish the progressive effects of climate policies. We also illustrate how using annual income deciles for distributional analysis instead of expenditure deciles can overstate the progressivity of emissions policies by overweighting revenue impacts on the lowest-income deciles.
Green superinsulation materials are essential for net-zero sustainable building envelopes. Realizing such potential is indispensable for simultaneously achieving carbon-sequestration and superinsulation performance. Here, we report the synthesis of a water glass-based silica aerogel exhibiting a thermal conductivity of 17.2 mW/m·K and a high porosity of 92%. Here, we used carbon-sequestration wheat straw fiber to create a gradient cellulose-aerogel composite to improve mechanical stability. The as-prepared gradient composite exhibits a thermal conductivity of 27.1 mW/m·K and a flexural modulus of 824 MPa, while exhibiting superhydrophobicity (water contact angle of 135.4°) for the development of green building insulation materials.