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This document is a response to concerns raised by Reershemius and Suhrhoff regarding a study conducted by Kantola et al. The authors of the response acknowledge that Reershemius and Suhrhoff did not find any faults with the derivation in the paper, which they state are factually true. They also mention that Reershemius and Suhrhoff arrived at a similar result in their own unpublished work. The response addresses specific implementation details raised by Reershemius and Suhrhoff and argues that these concerns lack merit. The authors appreciate the constructive engagement and transparency of data. [Extracted from the article]

Concern about climate change has led to policy to reduce CO2 emissions although it is likely that policy will have differential regional impacts. While regional impacts will be politically important, very little analysis of them has been carried out. This paper contributes to the analysis of this issue by building a small model involving two regions, incorporating the right to emit CO2 as a factor of production with the level of permitted emissions set by the national government. We argue that there is likely to be pressure on governments to use other policies to offset the possible adverse regional economic consequences of the pollution-reduction policy; we also consider a range of such policies. Using numerical simulation, we find that a 10 per cent reduction has relatively small but regionally differentiated economic effects. Standard fiscal policies are generally ineffective or counterproductive while labour market policies are more useful in offsetting the adverse effects. [ABSTRACT FROM AUTHOR]

This paper extends the analysis of our proposed modification to the first model of Libyan Exploration and Production Sharing Agreement ( LEPSA I) to field applications. Four decision-making models are coded in a spreadsheet program to estimate profitability indicators for two development scenarios. These scenarios are primary and secondary recovery methods with water injection and enhanced oil recovery by injecting carbon dioxide. The paper concludes that the economic profit for the foreign investor (second party) under LEPSA I was improved compared with EPSA IV. Also, Libya increased its oil reserves with a reasonable decrease of its production share. Moreover, the results showed that the profit indicators under the current production shares (cost recovery) of the fourth model of Exploration and Production Sharing Agreement ( EPSA IV) were not favourable to the second party. Because of that, the second party would not be motivated to make a decision to invest any money for an oil development projects in Libya. Finally, the paper investigates how EPSA IV should be redesigned to maximise the Libyan National Oil Corporation (first party) oil reserves and give more attention to the economic objectives of the second party. [ABSTRACT FROM AUTHOR]

The area of dedicated energy crops is expected to increase in Sweden. This will result in direct land use changes, which may affect the carbon stocks in soil and biomass, as well as yield levels and the use of inputs. Carbon dioxide ( CO2) fluxes of biomass are often not considered when calculating the climate impact in life cycle assessments ( LCA) assuming that the CO2 released at combustion has recently been captured by the biomass in question. With the extended time lag between capture and release of CO2 inherent in many perennial bioenergy systems, the relation between carbon neutrality and climate neutrality may be questioned. In this paper, previously published methodologies and models are combined in a methodological framework that can assist LCA practitioners in interpreting the time-dependent climate impact of a bioenergy system. The treatment of carbon differs from conventional LCA practice in that no distinction is made between fossil and biogenic carbon. A time-dependent indicator is used to enable a representation of the climate impact that is not dependent on the choice of a specific characterization time horizon or time of evaluation and that does not use characterization factors, such as global warming potential and global temperature potential. The indicator used to aid in the interpretation phase of this paper is global mean surface temperature change (Δ Ts( n)). A theoretical system producing willow for district heating was used to study land use change effects depending on previous land use and variations in the standing biomass carbon stocks. When replacing annual crops with willow this system presented a cooling contribution to Δ Ts( n). However, the first years after establishing the willow plantation it presented a warming contribution to Δ Ts( n). This behavior was due mainly to soil organic carbon ( SOC) variation. A rapid initial increase in standing biomass counteracted the initial SOC loss. [ABSTRACT FROM AUTHOR]

Keywords: carbon dioxide; hydrogenation; Cu-based catalyst; hydrogen enrichment; ethylene carbonate EN carbon dioxide hydrogenation Cu-based catalyst hydrogen enrichment ethylene carbonate 3599 3599 1 07/23/20 20200721 NES 200721 The Cover Feature shows a nanoflower-like Cu/SiO SB 2 sb catalyst of H SB 2 sb -enrichment capacity used for the hydrogenation of ethylene carbonate (EC) derived from CO SB 2 sb to produce methanol and ethylene glycol. In their Full Paper, M. Zhang, Y. Yang et al. synthesized the nanoflower-like copper catalysts with open-ended fibers and well-dispersed active species via one-step hydrolysis precipitation method. Carbon dioxide, hydrogenation, Cu-based catalyst, hydrogen enrichment, ethylene carbonate. [Extracted from the article]

Abstract: Carbon dioxide capture and storage (CCS) is an effective technology to reduce carbon dioxide (CO2) emissions in China. In this paper, the authors considered storage opportunities offered by oil reservoirs and deep saline aquifers in the Jiyang Depression, in east China. Based on detailed geological analysis and assessment of CO2 storage suitability, the Dongying Sag and Linyi‐Shanghe areas of the Huimin Sag within the Jiyang Depression appear promising for CO2 storage. Following more detailed characterization, the second and third members of the Shahejie Formation located in these two areas appear the most promising for CO2 storage. Within the areas identified as having potential for storage, 55 primary and 62 secondary recommended storage units were defined, with a total theoretical capacity of 5.02 × 108 tonnes (t) CO2. This represents storage of CO2 emissions from large‐scale sources in the Jiyang Depression for more than 30 years at current emission rates. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To explore how to use the waste heat and reduce the CO2 emissions of converter flue gas, a new process is proposed in this paper, performed by injecting pulverized coal into the hot gas using its waste heat to generate CO and further to achieve a secondary recovery of flue gas. Numerical simulations and industrial investigations are conducted. By comparing the injecting rate, the particle size, and the injecting velocity of the pulverized coal, an optimized scheme was obtained. The testing results show that, with increasing the injecting rate, the O2 and CO2 contents in the flue gas are reduced, while the CO and H2 contents are increased. When the injecting rate is 20 kg min−1, the O2 and CO2 contents are decreased by 72.16% and 50%, respectively, yet the CO and H2 contents are raised by 21.08% and 171.8%, respectively. The gas recovery time is extended by 10.12% and the carbon conversion is increased as much as 55%. Thus, the new process will be of great benefit to reduce CO2 emissions and increase the energy of converter gas. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1503–1512, 2018 [ABSTRACT FROM AUTHOR]

Abstract: Carbon dioxide (CO2) reduction in aqueous solutions is an attractive strategy for carbon capture and utilization. Cuprous oxide (Cu2O) is a promising catalyst for CO2 reduction as it can convert CO2 into valuable hydrocarbons and suppress the side hydrogen evolution reaction (HER). However, the nature of the active sites in Cu2O remains under debate because of the complex surface structure of Cu2O under reducing conditions, leading to limited guidance in designing improved Cu2O catalysts. This paper describes the functionality of surface‐bonded hydroxy groups on partially reduced Cu2O(111) for the CO2 reduction reaction (CO2RR) by combined density functional theory (DFT) calculations and experimental studies. We find that the surface hydroxy groups play a crucial role in the CO2RR and HER, and a moderate coverage of hydroxy groups is optimal for promotion of the CO2RR and suppression of the HER simultaneously. Electronic structure analysis indicates that the charge transfer from hydroxy groups to coordination‐unsaturated Cu (CuCUS) sites stabilizes surface‐adsorbed COOH*, which is a key intermediate during the CO2RR. Moreover, the CO2RR was evaluated over Cu2O octahedral catalysts with {111} facets and different surface coverages of hydroxy groups, which demonstrates that Cu2O octahedra with moderate coverage of hydroxy groups can indeed enhance the CO2RR and suppress the HER. [ABSTRACT FROM AUTHOR]

Abstract: Electrochemical reduction of carbon dioxide (CO2) into value‐added chemicals is a promising strategy to reduce CO2 emission and mitigate climate change. One of the most serious problems in electrocatalytic CO2 reduction (CO2R) is the low solubility of CO2 in an aqueous electrolyte, which significantly limits the cathodic reaction rate. This paper proposes a facile method of catholyte‐free electrocatalytic CO2 reduction to avoid the solubility limitation using commercial tin nanoparticles as a cathode catalyst. Interestingly, as the reaction temperature rises from 303 K to 363 K, the partial current density (PCD) of formate improves more than two times with 52.9 mA cm−2, despite the decrease in CO2 solubility. Furthermore, a significantly high formate concentration of 41.5 g L−1 is obtained as a one‐path product at 343 K with high PCD (51.7 mA cm−2) and high Faradaic efficiency (93.3 %) via continuous operation in a full flow cell at a low cell voltage of 2.2 V. [ABSTRACT FROM AUTHOR]

In this paper, the effect of additive Fe on Ni/Al2O3 catalyst for CO2 methanation was studied. A series of bimetallic Ni–Fe catalysts with different Ni/Fe ratios were prepared by impregnation method. For comparison, monometallic Fe‐based and Ni‐based catalysts were also prepared by the same method. The characterization results showed that adding Fe to Ni catalyst on the premise of a low Ni loading(≦12 wt.%) enhanced CO2 methanation performance. However, when the Ni loading reached 12 wt.%, the catalytic activity decreased with the increase of Fe content, but still higher than the corresponding Ni‐based catalyst without Fe. Among them, the 12Ni3Fe catalyst exhibited the highest CO2 conversion of 84.3 % and nearly 100% CH4 selectivity at 50000 ml g‐1 h‐1 and 420 °C. The enhancement effect of adding Fe on CO2 methanation was attributed to the dual effect of suitable electronic environment and increased reducibility generated by Fe species. [ABSTRACT FROM AUTHOR]

Shrub encroachment is a well-documented phenomenon affecting many of the world's drylands. The alteration of vegetation structure and species composition can lead to changes in local microclimate and soil properties which in turn affect carbon cycling. The objectives of this paper were to quantify differences in air temperatures, soil carbon, nitrogen, and CO2 efflux under trees (Vachellia erioloba), shrubs (Grewia flava), and annual and perennial grasses (Schmidtia kalahariensis and Eragrostis lehmanniana) collected over three seasons at a site in Kgalagadi District, Botswana, in order to determine the vegetation-soil feedback mechanism affecting the carbon cycle. Air temperatures were logged continuously, and soil CO2 efflux was determined throughout the day and evening using closed respiration chambers and an infrared gas analyser. There were significant differences in soil carbon, total nitrogen, CO2 efflux, light, and temperatures beneath the canopies of trees, shrubs, and grasses. Daytime air temperatures beneath shrubs and trees were cooler compared with grass sites, particularly in summer months. Night-time air temperatures under shrubs and trees were, however, warmer than at the grass sites. There was also significantly more soil carbon, nitrogen, and CO2 efflux under shrubs and trees compared with grasses. Although the differences observed in soils and microclimate may reinforce the competitive dominance of shrubs and present challenges to strategies designed to manage encroachment, they should not be viewed as entirely negative. Our findings highlight some of the dichotomies and challenges to be addressed before interventions aiming to bring about more sustainable land management can be implemented. [ABSTRACT FROM AUTHOR]

Abstract: An alternative of wellbore cement system, formed through alkali‐activation of fly ashes also knows as fly ash geopolymers, provides attractive properties due to its high compressive strength and durability against acidic conditions. However, changes in microstructure and mineralogical during accelerated carbonation affected by CO2 alteration under elevated temperature and pressure have not been fully understood. This paper investigates and characterizes the alkali‐activated binders fly ash based in the acidic environment under elevated temperature and pressure. The results found that scales such a layer was formed in the gel phase at the spherical surface of fly ash after carbonation process. The effect is that the surface of the gel phase became rough and porous. Carbonate and/or bicarbonate salts were identified as major phase in the sample after immersion test. In the activated fly ash cement, both calcium aluminate silicate hydrate (C–A–S–H) and sodium aluminosilicate hydrate (N–A–S–H) gels were formed; C–A–S–H gel was decalcified, forming calcium carbonate phase in the form of calcite, aragonite or vaterite. These findings were confirmed by the analysis and identification of Fourier‐transformed infrared spectroscopy, X‐ray diffraction and scanning electron microscopy tests on the changes in the cement system. [ABSTRACT FROM AUTHOR]

Abstract: Climate change has been described as the biggest global health threat of the 21st century. The atmospheric concentrations of greenhouse gases, such as carbon dioxide, methane and nitrous oxide, have increased significantly since the start of the Industrial Era around 1750, with much of this increase occurring over just the last 50 years or so. This is resulting in warming of the climate system as well as changes in precipitation and weather and climate extremes. These changes in climate are having wide‐ranging impacts on the Earth’s physical, biological and human systems, including human health. It is these impacts of climate change on human health that are the focus of this paper, particularly the impacts on allergens and allergic diseases. Such impacts are particularly significant in many countries where the prevalence of such diseases is high and/or increasing. There is now compelling evidence that rising air temperatures and carbon dioxide concentrations are, in some plant species, resulting in increased pollen production and allergenicity and advancement and lengthening of the pollen season. Changes in extreme events, such as thunderstorms and tropical cyclones, will also have impacts on allergic diseases, with, for example, the flooding associated with tropical cyclones leading to proliferation of mould growth in damp homes. The article also considers a range of responses to these health threats, including greenhouse gas mitigation, and adaptation strategies, such as enhanced environmental monitoring and health surveillance and adequate planning for the future medical workforce. [ABSTRACT FROM AUTHOR]

This review was undertaken to draw together research on how climate change impacts sugarcane production, and to assess the implications of climate change for the sugarcane industry, as well as possible response options. Much of the extant research examines how changes in climate lead to changes in primary production; however, few studies consider how climate change translates into industry-wide impacts and economic consequences across the sugarcane value chain. Of the 90 studies we reviewed (published as journal articles, proceedings, and book chapters), 61 assess observed and/or projected impacts of climate change on sugarcane production. These studies reach largely different conclusions regarding how increases in air temperature or atmospheric carbon dioxide levels impact sugarcane production. These mixed results can be attributed to differences between the studies in terms of methods, time frames, and growing regions, which all limit cross-study comparability. A total of 17 studies focus on the adaptation to observed and/or projected impacts of climate change, such as changed management procedures or farming practices, but there is limited evidence regarding successful adaptation outcomes. In addition, a separate stream of papers discusses mitigating energy use and greenhouse gas emissions in the sugarcane production process, often with a view to reducing environmental impacts. Our review concludes by outlining the pathways for future research, highlighting that further insights are needed in particular regarding the economic consequences of climate change for the sugarcane industry. WIREs Clim Change 2018, 9:e498. doi: 10.1002/wcc.498 This article is categorized under: Future of Global Energy > Evaluating Future Impacts of Climate Change [ABSTRACT FROM AUTHOR]

The National Risk Assessment Partnership (NRAP) has developed a suite of tools to assess and manage risk at CO2 sequestration sites. The NRAP tool suite includes the Aquifer Impact Model (AIM), which evaluates the potential for groundwater impacts from leaks of CO2 and brine through abandoned wellbores. There are two aquifer reduced-order models (ROMs) included with the AIM tool, a confined alluvium aquifer, and an unconfined carbonate aquifer. The models accept aquifer parameters as a range of variable inputs so they may have broad applicability. The generic aquifer models may be used at the early stages of site selection, when site-specific data is not available. Guidelines have been developed for determining when the generic ROMs might be applicable to a new site. This paper considers the application of the AIM to predicting the impact of CO2 or brine leakage were it to occur at the Illinois Basin Decatur Project (IBDP). Results of the model sensitivity analysis can help guide characterization efforts; the hydraulic parameters and leakage source term magnitude are more sensitive than clay fraction or cation exchange capacity. Sand permeability was the only hydraulic parameter measured at the IBDP site. More information on the other hydraulic parameters could reduce uncertainty in risk estimates. Some non-adjustable parameters are significantly different for the ROM than for the observations at the IBDP site. The generic ROMs could be made more useful to a wider range of sites if the initial conditions and no-impact threshold values were adjustable parameters. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Density-driven convection has been identified to accelerate the rate of CO2 solubility trapping during geological CO2 storage in deep saline aquifers. In this paper, we present an experimental method using the refractive properties of fluids (their impact on light transmission), and an analogous system design, which enables the study of transport mechanisms in saturated porous media. The method is used to investigate solutally induced density-driven convective mixing under conditions relevant to geological CO2 storage. The analogous system design allows us by choice of initial solute concentration and bead size to duplicate a wide range of conditions (Ra-values), making it possible to study the convective process in general, and as a laboratory analogue for systems found in the field. We show that the method accurately determines the solute concentration in the system with high spatial and temporal resolution. The onset time of convection (tc), mass flux (F), and flow dynamics are quantified and compared with experimental and numerical findings in the literature. Our data yield a scaling law for tc which gives new insight into its dependence on Ra, indicating tc to be more sensitive to large Ra than previously thought. Furthermore, our data show and explain why F is described equally well by a Ra-dependent or a Ra-independent scaling law. These findings improve the understanding of the physical process of convective mixing in saturated porous media in general and help to assess the CO2 solubility trapping rate under certain field conditions. [ABSTRACT FROM AUTHOR]

CO2 leakage is a major concern in a geological carbon sequestration projects due to adverse environmental consequences, where the main leakage risk is identified to be along existing wells through a thick, low-permeable cap rock. To pursue robust and cost effective real-time downhole monitoring technology for CO2 sequestration wellbore integrity, a permanently deployed coaxial cable casing imager is developed and evaluated in laboratory in this paper. The prototype of the casing imager consists of evenly distributed coaxial cable strain sensors helically wrapped around the pipe. The system is deployed on both PVC pipe and steel pipe to test its performance in casing deformation monitoring, including axial compression, radial expansion, bending, and ovalization. The strain sensors are pre-stressed and then helically wrapped onto the pipe with high strength epoxy. Multiple linear variable differential transformers (LVDTs) or strain gauges are used as an independent measurement of the actual pipe deformation in comparison to the casing imager measured pipe deformation. The test results demonstrated the ability of the lab-scale casing imager prototype in real-time casing deformation monitoring, including axial compression, radial expansion, bending, and ovalization, which would prove of great value in evaluating wellbore integrity state and providing early warnings of leakage risk that will contaminate the groundwater during CO2 injection. The low cost and high robustness of the distributed coaxial cable sensors will greatly lower the downhole monitoring cost and increase the system longevity. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Polymer systems displaying CO2-triggered rheology alteration are widely investigated in recent years, which can change from nonviscous liquid to high-viscosity solution or even gel by passing CO2 through. Among those polymer systems, a previous study of the group shows that a rationally designed ABA-type triblock copolymer with a hydrophilic middle block and two CO2-responsive end blocks can undergo either gel-sol or sol-gel transition triggered by CO2 as a result of increase or decrease in lower critical solution temperature of A blocks, respectively. This paper describes a new and more flexible approach to achieving CO2-induced gelation of polymer aqueous solution at much lower polymer concentrations. It consists in mixing two water-soluble ABA triblock copolymers that have the same B block but different A blocks: for one polymer, the A blocks are a negatively charged polyelectrolyte, and for the other polymer, the A blocks can be turned positively charged under CO2 stimulation. In this way, CO2 bubbling through an aqueous solution of the two constituent triblock copolymers can induce complexation of the oppositely charged A blocks and, as a result, gelation of the solution of mixed triblock copolymers. [ABSTRACT FROM AUTHOR]

The equilibrium climate sensitivity estimated from different sources is inconsistent due to its dependence on the surface warming pattern. Cloud feedbacks have been identified as the major contributor to this so‐called pattern effect. We find a large unforced pattern effect in CERES data, with cloud feedback estimated from two consecutive 125‐month periods (March 2000–July 2010 and August 2010–December 2020) changing from −0.45 ± 0.85 to +1.2 ± 0.78 W/m2/K. When comparing to models, 27% of consecutive 10‐year segments in CMIP6 control runs have differences similar to the observations. We also compare the spatial patterns in the CERES data to those in climate models and find they are similar, with the East Pacific playing a key role. This suggests that the impact of the unforced pattern effect can be significant and that models are capable of reproducing its global‐average magnitude. Plain Language Summary: Climate sensitivity, the amount of surface warming in response to increasing carbon dioxide, is often used as a metric to quantify the severity of climate change. The estimates of climate sensitivity from different sources, however, are not consistent. The main reason is that the response of clouds to surface temperature changes, called cloud feedback, depends on the spatial pattern of surface warming. We investigate the impact of this so‐called pattern effect on cloud feedback in observations and climate models. Here we find that the observed cloud feedbacks calculated from two consecutive decades have significant differences in both global mean value and spatial pattern, and the climate models produce similar results. This highlights the fact that differences of surface warming patterns can have large influences on cloud feedbacks, and climate models have the ability to reproduce what happened in the real world. Key Points: The difference in cloud feedback between two ∼10‐year periods inferred from CERES is 1.6 ± 1.1 W/m2/KThe distinct difference in cloud feedback verifies the existence of a large unforced pattern effectCMIP6 models produce unforced pattern effects of similar magnitude and spatial structure to those seen in the observations [ABSTRACT FROM AUTHOR]

Gallium hydrides stabilised by primary and secondary amines are scarce due to their propensity to eliminate dihydrogen. Consequently, their reactivity has received limited attention. The synthesis of two novel gallium hydride complexes HGa(THF)[ON(H)O] and H2Ga[μ2‐ON(H)O]Ga[ON(H)O] ([ON(H)O]2−=N,N‐bis(3,5‐di‐tert‐butyl‐2‐phenoxy)amine) is described and their reactivity towards aldehydes and ketones is explored. These reactions afford alkoxide‐bridged dimers through 1,2‐hydrogallation reactions. The gallium hydrides can be regenerated through Ga−O/B−H metathesis from the reaction of such dimers with pinacol borane (HBpin) or 9‐borabicyclo[3.3.1]nonane (9‐BBN). These observations allowed us to target the catalytic reduction of carbonyl substrates (aldehydes, ketones and carbon dioxide) with low catalyst loadings at room temperature. [ABSTRACT FROM AUTHOR]

Industrial‐scale reforming of methane is typically carried out with an excess of oxidant to suppress coking of the catalyst. On the other hand, many academic studies on dry reforming employ a CO2/CH4 ratio of unity to quickly observe coking which can be reduced by adding a catalyst promoter. In this work, Ni/Al2O3 catalysts were tested for dry reforming of methane (CO2/CH4=1) with additional regeneration steps to test the resistance against an oxidation treatment. Thereby, we wanted to evaluate catalyst stability for industrial relevance. The effects of three promoters, Cr, Mn and Fe, that differ in their degree of CO2 interaction, are compared. A higher iron loading on Ni/Al2O3 leads to higher stability in dry reforming with lower coke formation. However, the higher the concentration of a promoter with high CO2 affinity, the quicker the catalyst is oxidized during regeneration with CO2. Subsequent reduction of a catalyst oxidized with CO2 leads to considerable sintering in all cases. This sintering induces formation of more coke during dry reforming. On such sintered samples only highly effective promoters in large concentrations still have a noticeable effect compared to unpromoted Ni/Al2O3. [ABSTRACT FROM AUTHOR]

Evidence is provided that in a gas‐solid photocatalytic reaction the removal of photogenerated holes from a titania (TiO2) photocatalyst is always detrimental for photocatalytic CO2 reduction. The coupling of the reaction to a sacrificial oxidation reaction hinders or entirely prohibits the formation of CH4 as a reduction product. This agrees with earlier work in which the detrimental effect of oxygen‐evolving cocatalysts was demonstrated. Photocatalytic alcohol oxidation or even overall water splitting proceeds in these reaction systems, but carbon‐containing products from CO2 reduction are no longer observed. H2 addition is also detrimental, either because it scavenges holes or because it is not an efficient proton donor on TiO2. The results are discussed in light of previously suggested reaction mechanisms for photocatalytic CO2 reduction. The formation of CH4 from CO2 is likely not a linear sequence of reduction steps but includes oxidative elementary steps. Furthermore, new hypotheses on the origin of the required protons are suggested. [ABSTRACT FROM AUTHOR]

Ocean mesoscale flows significantly influence nutrient distribution and biological productivity, yet the scarcity of eddy‐permitting observational data sets and climate modeling hinders understanding their role in carbon sequestration. Using an eddy‐resolving global simulation, this study investigates the significance of ocean mesoscales in air‐sea carbon dioxide (CO2) exchange. Results show over 30% of CO2 flux variance in energetic regions attributed to flows with horizontal scales smaller than 2°. Mesoscale flows can drive a cumulative CO2 flux that is either a net carbon sink or source depending on region, with magnitudes on the order of 105 tonnes of carbon per year. Variations in this mesoscale‐related CO2 flux are correlated with local relative vorticity and the background gradient of ocean partial pressure of CO2. This analysis underscores the importance of considering ocean mesoscales in monitoring carbon flux, highlighting the need to explore the influence of increasing eddy activity on carbon uptake in a changing climate. Plain Language Summary: This study investigates the influence of ocean flows with horizontal scales of tens to hundreds of kilometers (called mesoscale flows) on the exchange of carbon dioxide between the ocean and the atmosphere using a state‐of‐the‐art high resolution global simulation. It is shown that in certain parts of the ocean, more than 30% of the variability in carbon dioxide exchange at the ocean surface is linked to these relatively small‐scale ocean motions. It is further revealed that mesoscale flows can lead to a significant gain or loss of carbon from the ocean at the regional level, and that depends on how the flow is oriented with respect to the background distribution of carbon in the ocean. Gaining a better understanding of how the mesoscale flow features influence air‐sea carbon dioxide exchange is crucial for understanding the ocean's role in the carbon cycle and its ability to absorb and store carbon in a changing climate. Key Points: Over 30% of air‐sea CO2 flux variability is attributed to ocean spatial scales smaller than 2° in eddy‐rich regionsThe cumulative mesoscale‐induced CO2 flux is on the order of 105 tonnes of carbon per yearMesoscale‐related CO2 flux is governed by both relative vorticity and the background gradient of partial pressure of CO2 [ABSTRACT FROM AUTHOR]

Incorporating large amounts of woody biomass into soil, such as in whole orchard recycling (WOR), can promote carbon sequestration, nutrient recycling, and ecosystem health in agricultural fields. Yet uncertainty regarding the effects of WOR on soil carbon (C) and nitrogen (N) dynamics influences management decisions. The objective of this research was to evaluate the effects of woodchip (WC) size and interaction with N fertilization on carbon dioxide (CO2) and nitrous oxide (N2O) emissions. An 8‐month incubation experiment incorporating WC (4% w/w, equivalent to ∼40 tons per acre) in four sieved sizes (0.2–1.6, 1.6–3.2, 3.2–6.4, and 6.4–12.7 mm) with and without N applications was conducted. All treatments with WC showed that CO2 emission peaked within the first week, then decreased drastically afterward. The CO2 peak delayed as the peak value decreased (WC size increased). The finest WC (<1.6 mm) yielded the lowest total CO2 emissions and resulted in the greatest increase in soil C at the end of incubation. Nitrogen application reduced total CO2 emissions by 1% in the smallest WC size and by 8%–9% for those larger than 1.6 mm. The N2O emissions spiked following each fertilizer application with lowest total emissions from the smallest WC size, suggesting substantial N immobilization. The results imply that larger WC sizes can delay C mineralization and reduce initial N immobilization risks, but the smallest WC size may have stabilized and increased soil organic carbon. This research increased our understanding on WC mineralization that can be used in WOR management. Core Ideas: There is a significant interaction between woodchip size and N application on both CO2 and N2O emissions.Smallest woodchip size gave highest initial CO2 emissions, but lowest total loss while increasing soil organic carbon.N application with woodchips resulted in significantly lower CO2 emissions.Woodchip size showed different impact on peak N2O emissions with time but no impact on total loss and soil N.Larger woodchip sizes showed delay in C mineralization, minimizing the initial N immobilization risk. [ABSTRACT FROM AUTHOR]

N‐coordinated Ni sites (NiNx) are effective catalysts for the electrochemical reduction of CO2 to CO. In most researches, modulating the coordination environment of Ni atoms is focused on to improve electrochemical CO2 reduction (ECR) performance. However, the influence of the carbon substrate's structure on the intrinsic activity of NiNx is seldom investigated. The highly curved surface of carbon nanotubes (CNT) may provide a unique curvature effect on NiNx. It is found that the Ni residues in CNT can be atomized to form NiNx sites on the surface of CNT (Ni‐N/CNT@covalent triazine framework [CTF]) through high‐temperature pyrolysis, using a soluble CTF nanosheet as N precursor. The π‐conjugated and ultrathin 2D structure of CTF enables closer interfacial contact between CTF and CNT, which avoids the formation of a thick carbon layer to maximize the curvature effect. Theoretical data reveal that the NiN3 configuration may act as a highly active ECR site, and the curvature effect from CNT can further tune the electronic structure of NiN3, thus improving the ECR kinetics. The Ni‐N/CNT@CTF‐based flow‐cell electrolyzer exhibits a jCO of 201 mA cm−2 at −0.9 V with a high FECO of 98%. [ABSTRACT FROM AUTHOR]

In current research, achieving carbon neutrality has become a primary focus through the utilization of various conversion technologies that transform carbon dioxide (CO2) into valuable chemicals or fuels. Covalent organic frameworks (COFs), as emerging crystalline organic polymers, offer distinct advantages in CO2 conversion compared to other materials. These advantages include controllable nanoscale pores, predefined functional units, editable framework structures, and rich conjugated systems. The unique characteristics of COFs make them highly promising electrocatalysts for CO2 conversion. This review provides a comprehensive overview of pioneering works and recent research on the utilization of COF‐based materials as electrocatalysts for electrochemical CO2 reduction reaction. This review offers a comprehensive analysis of the design principles for various reactive sites, skeleton structures, pore functionalities, 3D frameworks, morphologies, and composite materials of COFs, aiming to enhance electrocatalysis. Finally, this review presents some recommendations for material design, reaction mechanisms, and theoretical computations to enhance the understanding of reaction mechanisms further and facilitate the design of high‐performance COF‐based electrocatalysts. [ABSTRACT FROM AUTHOR]

Conversion of carbon dioxide (CO2) to valuable chemicals and feedstocks through electrochemical reduction holds promise for achieving carbon neutrality and mitigating global warming. C2+ products are of interest due to their higher economic value. Since the CO2 to C2+ conversion process involves multiple steps, tandem catalytic strategies are commonly employed in the design of electrochemical CO2 reduction reaction (CO2RR) catalysts and systems/reactors. Among the diverse catalysts that are capable of reducing CO2 to CO, Cu stands out for more efficiently further converting CO to C2+ products. In this review, the emerging Cu‐based tandem catalysts and their impact on CO2RR performance, focusing on three positional relationships are summarized. It delves into the integration of tandem catalytic strategies into membrane electrolyzers, utilizing catalyst‐coated substrate (CCS) and catalyst‐coated membrane (CCM) technologies. Several typical examples are presented to illustrate this integration. Finally, the challenges and prospects of applying tandem strategies in the development of CO2RR catalysts/systems, as well as their device‐level implementation are indicated. [ABSTRACT FROM AUTHOR]

To reach their net‐zero targets, countries will have to compensate hard‐to‐abate CO2 emissions through carbon dioxide removal (CDR). Yet, current assessments rarely include socio‐cultural or institutional aspects or fail to contextualize CDR options for implementation. Here we present a context‐specific feasibility assessment of CDR options for the example of Germany. We assess 14 CDR options, including three chemical carbon capture options, six options for bioenergy combined with carbon capture and storage (BECCS), and five options that aim to increase ecosystem carbon uptake. The assessment addresses technological, economic, environmental, institutional, social‐cultural and systemic considerations using a traffic‐light system to evaluate implementation opportunities and hurdles. We find that in Germany CDR options like cover crops or seagrass restoration currently face comparably low implementation hurdles in terms of technological, economic, or environmental feasibility and low institutional or social opposition but show comparably small CO2 removal potentials. In contrast, some BECCS options that show high CDR potentials face significant techno‐economic, societal and institutional hurdles when it comes to the geological storage of CO2. While a combination of CDR options is likely required to meet the net‐zero target in Germany, the current climate protection law includes a limited set of options. Our analysis aims to provide comprehensive information on CDR hurdles and possibilities for Germany for use in further research on CDR options, climate, and energy scenario development, as well as an effective decision support basis for various actors. Plain Language Summary: Countries aiming to achieve net‐zero emissions will have to remove the remaining carbon dioxide from the atmosphere through carbon dioxide removal (CDR). However, current assessments of CDR options rarely consider socio‐cultural or institutional aspects or set the CDR options in the specific context of their implementation. In this study, researchers conducted the first context‐specific feasibility assessment of CDR options in Germany, considering six dimensions, including technological, economic, environmental, institutional, and social‐cultural aspects. The study assessed 14 CDR options, including chemical carbon capture options, bioenergy combined with carbon capture and storage, and options to increase ecosystem carbon uptake. The study found that CDR options like cover crops or seagrass restoration face low implementation hurdles but have small CO2 removal potentials, while options like woody‐biomass combustion or mixed‐feedstock biogas production have high CDR potentials but face large economic and institutional hurdles. The analysis aims to provide comprehensive information on CDR options for use in further research and as an effective decision support basis for a range of actors. Key Points: More context‐specific assessments of carbon dioxide removal (CDR) options are needed to guide national net‐zero decision makingEcosystem‐based CDR options with comparably low implementation hurdles in Germany show relatively small CO2 removal potentialsHigh CDR potential options in Germany face high institutional, technological and societal hurdles linked in many ways to geological storage [ABSTRACT FROM AUTHOR]

Large‐scale implementation of electrochemical CO2 conversion to value‐added products is currently hampered by high electrolyzer cell voltages, resulting in low energy efficiency and high operating costs. Cell voltages are typically well above 3 V and need to be significantly lowered whilst maintaining current densities greater than 200 mA cm−2 to enable energy‐efficient CO2 electroreduction. This can be addressed through modification of the resistive components of the device to reduce energy consumption and lower operating costs. Electrodes, electrolyte solutions, and the separator between compartments, provide the largest contributions to the overall cell voltage, therefore decreasing their resistance can lower the electricity input required to drive effective CO2 conversion. Here, by careful analysis and tuning of the various sources of voltage drops within the cell, an optimized diaphragm‐based CO2R device is presented, which is able to operate at an industrially relevant current density of 200 mA cm−2 with an |Ecell| as low as 2.89 V, amongst the lowest reported values to date. [ABSTRACT FROM AUTHOR]

Multiphysics modeling enables probing of conditions inside a CO2 electrolyzer that are difficult to measure, such as local concentrations and pH, as well as rapid testing of possible design changes. A one‐dimensional model for a zero‐gap membrane electrode assembly (MEA) CO2 electrolyzer was developed with the assumption that catalyst layers interact with the membrane ionomer such that the ionomer affects the underlying kinetics. The kinetics for bicarbonate reacting to form hydrogen are fit using a planar electrode model for silver with an ionomer coating. The MEA model results are validated against experimental studies for current density and product selectivity. Flooding of the cathode is modeled using saturation curves, and results show that blocked pores in the microporous layer play a significant role in limiting the mass transport at high potentials (>2.8 V). Sensitivity studies showed that CO Faradaic efficiency can be increased by decreasing catalyst layer thickness and porosity, and decreasing KHCO3 concentration. [ABSTRACT FROM AUTHOR]

Current estimates of carbon dioxide (CO2) evasion from Arctic lakes are highly uncertain because few studies integrate seasonal variability, specifically evasion during spring ice‐melt. We quantified annual CO2 evasion for 14 clear‐water Arctic lakes in Northern Sweden through mass balance (ice‐melt period) and high‐frequency loggers (open‐water period). On average, 80% (SD: ± 18) of annual CO2 evasion occurred within 10 d following ice‐melt. The contribution of the ice‐melt period to annual CO2 evasion was high compared to earlier studies of Arctic lakes (47% ± 32%). Across all lakes, the proportion of ice‐melt : annual CO2 evasion was negatively related to the dissolved organic carbon concentration and positively related to the mean depth of the lakes. The results emphasize the need for measurements of CO2 exchange at ice‐melt to accurately quantify CO2 evasion from Arctic lakes. [ABSTRACT FROM AUTHOR]

An unprecedented Et2Zn‐mediated gem‐dicarboxylation of C─C/C─H single bond of cyclopropanols with CO2 is disclosed, which provides a straightforward and efficient methodology for the synthesis of a variety of structurally diverse and useful malonic acids in moderate to excellent yields. The protocol features mild reaction conditions, excellent functional group compatibility, broad substrate scope, and facile derivatization of the products. DFT calculations confirm that the transition‐metal‐free transformation proceeds through a novel ring‐opening/α‐functionalization/ring‐closing/ring‐opening/β‐functionalization (ROFCOF) process, and 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) plays dual important roles in the transformation. [ABSTRACT FROM AUTHOR]

Crop models are often used to project future crop yield under climate and global change and typically show a broad range of outcomes. To understand differences in modeled responses, we analyzed modeled crop yield response types using impact response surfaces along four drivers of crop yield: carbon dioxide (C), temperature (T), water (W), and nitrogen (N). Crop yield response types help to understand differences in simulated responses per driver and their combinations rather than aggregated changes in yields as the result of simultaneous changes in various drivers. We find that models' sensitivities to the individual drivers are substantially different and often more different across models than across regions. There is some agreement across models with respect to the spatial patterns of response types but strong differences in the distribution of response types across models and their configurations suggests that models need to undergo further scrutiny. We suggest establishing standards in model evaluation based on emergent functionality not only against historical yield observations but also against dedicated experiments across different drivers to analyze emergent functional patterns of crop models. Plain Language Summary: Crop models are widely used to compute crop yields under future climate change. Yields are determined by many interacting processes. Simulated future crop yields often show a broad uncertainty range. We investigate the sensitivity of nine different crop models to individual model inputs (carbon dioxide, temperature, water, nitrogen) in a very large simulation data set and find that there are substantial differences. We conclude that crop model evaluation needs to include analyses of functional properties to avoid that very diverse model responses to drivers are not tracked if interacting processes cancel out in the historical evaluation period but not in future scenarios, leading to large differences between models. Key Points: Crop models show strong differences in input sensitivitiesStandardized modeling experiments reveal differences in emergent functional relationshipsNew standards in model evaluation are needed [ABSTRACT FROM AUTHOR]

Keywords: acidosis; atmosphere; carbon dioxide; infant development EN acidosis atmosphere carbon dioxide infant development 1037 1037 1 03/03/23 20230301 NES 230301 Wyrwoll et al. ([2]) compared some possible effects of raised atmospheric CO SB 2 sb (890 ppm) on a range of behavioural and developmental parameters in the offspring of pregnant rats following exposure from preconception to 3 months of age. Misunderstanding of the contribution of climate change to inspired CO2 and acid-base balance in pregnant women: It is not a hazard to their offspring An atmospheric CO SB 2 sb of 460 ppm = 0.35 mmHg CO SB 2 sb in air at 1 atmosphere and 890 ppm = 0.676 mmHg. [Extracted from the article]

Carbon dioxide (CO2) emissions from biomass combustion are traditionally assumed climate neutral if the bioenergy system is carbon (C) flux neutral, i.e. the CO2 released from biofuel combustion approximately equals the amount of CO2 sequestered in biomass. This convention, widely adopted in life cycle assessment (LCA) studies of bioenergy systems, underestimates the climate impact of bioenergy. Besides CO2 emissions from permanent C losses, CO2 emissions from C flux neutral systems (that is from temporary C losses) also contribute to climate change: before being captured by biomass regrowth, CO2 molecules spend time in the atmosphere and contribute to global warming. In this paper, a method to estimate the climate impact of CO2 emissions from biomass combustion is proposed. Our method uses CO2 impulse response functions (IRF) from C cycle models in the elaboration of atmospheric decay functions for biomass-derived CO2 emissions. Their contributions to global warming are then quantified with a unit-based index, the GWPbio. Since this index is expressed as a function of the rotation period of the biomass, our results can be applied to CO2 emissions from combustion of all the different biomass species, from annual row crops to slower growing boreal forest. [ABSTRACT FROM AUTHOR]

For business and environmental reasons, increased understanding of green consumer behavior is essential. This paper addresses consumer adoption and non-adoption of a high involvement eco-innovation (the alternative fuel vehicle, AFV). The purpose is to integrate two research streams to explore factors driving and hindering adoption. The factors are rooted in environmental psychology research and the diffusion of innovation literature. Survey results on Swedish car owners are reported. The results indicate that adopters and non-adopters differ on norms, attitudes, novelty seeking and on how innovation attributes are perceived. Furthermore, the results show that the groups rank car attributes such as fuel consumption and carbon dioxide emissions differently. The main contribution of the paper is the integration of norms and attitudes together with consumer adoption factors in analyzing green consumer behavior in relation to a high involvement product. The implications for business and marketing strategy and for environmental policy are discussed. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment. [ABSTRACT FROM AUTHOR]

The effects of carbon dioxide and the induction of morbidity on aversion learning in larvae of the Pacific Coast wireworm Limonius canus LeConte (Coleoptera: Elateridae) are discussed. Wireworms preconditioned by exposing them one or four times to odour of Tefluthrin 20SC and Dividend XLRTA [Syngenta Crop Protection (Canada), Inc., Canada] during the induction of temporary morbidity subsequently contact tefluthrin-treated wheat seeds in soil bioassays for as long as naïve (i.e. not preconditioned) larvae but are repelled four to five-fold more frequently by Dividend-treated seeds in soil bioassays than naïve wireworms, suggesting that wireworms are capable of associating a novel odour (i.e. Dividend) with morbidity but require a minimum of 10–15 min subsequent contact time with treated seeds before being repelled. Wireworms preconditioned by exposure to peppermint odour during the induction of morbidity are not subsequently repelled by peppermint odour in soil bioassays, suggesting that wireworms are either not capable of aversion learning or that the presence of a CO2 source and/or a suitable host plant may override a negative cue (i.e. peppermint odour). In studies conducted in the absence of soil, a host plant and CO2 production, wireworms are repelled slightly by droplets of 1.0% but not 0.1% peppermint oil. Previous exposure to peppermint odour or contact with peppermint oil-treated filter paper during one induction of morbidity does not increase the repellency of wireworms to 1.0% peppermint oil significantly. Repellency to 1.0% peppermint oil is almost eliminated when morbidity is induced five times in the absence of peppermint odour but is restored when peppermint odour is present during preconditioning. These findings suggest that wireworm sensitivity to repellent compounds decreases when repeatedly made moribund, although the results are not sufficient to conclude that wireworms are capable of associative learning. [ABSTRACT FROM AUTHOR]

Dutch glasshouse firms are facing the introduction of a system of tradable CO2 emission quotas. This paper employs a non-parametric method for modelling tradable CO2 emissions of Dutch glasshouse firms. The method is capable of generating shifts in CO2 emissions across the sample of firms. Moreover, changes in volumes of outputs produced and inputs used are computed. Results show that firms using a conventional heating technology will be net purchasers of CO2 emissions, whereas firms using more advanced heating technologies will sell part of their emission quota. [ABSTRACT FROM AUTHOR]

This paper provides the theoretical calculation results of thermodynamic and transport properties of CO2, CO2–O2 mixture, CO2–H2 mixture under thermal equilibrium condition at temperatures of 300 to 30,000 K and at pressures of 0.1 to 10 MPa. The gas CO2 is one of the candidates for the environmentally benign arc-quenching medium in a circuit breaker. Furthermore, the effect of additional gases O2 and H2 on the thermodynamic and transport properties of CO2 was also investigated in this paper. The hydrogen atom included CO2 is similar to the polymer ablated vapor in switching devices. First, equilibrium compositions of CO2, CO2–O2 mixture, CO2–H2 mixture were calculated through the Gibbs free energy minimization method. Second, thermodynamic properties were computed using the calculated composition. Finally, transport properties were calculated by the first-order approximation of Chapman– Enskog method using the collision integrals between species. Inclusion of H2 increases the electrical conductivity of CO2 in the range 3000 to 6000 K because CHO molecules produced in this temperature range emit more electrons due to the lower ionization potential of CHO. It also increases the thermal conductivity of CO2 especially due to dissociation reactions of H2 around 3900 K and ionization of H around 15,000 K. These properties provided here can be used for CO2 thermal plasma simulation. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(4): 18–29, 2008; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20467 [ABSTRACT FROM AUTHOR]

Abatement of CO2 emission is one of the most important issues in the 21st century regarding preservation of the earth environment. This paper addresses a utility operations planning problem for distributed energy management systems (DEMSs), where we are to obtain optimal plans that minimize both costs and CO2 emissions. A DEMS consists of multiple entities that seek their own economic profits. In this paper, we give a mathematical formulation of the utility operations planning problem for each entity, and propose an energy trading market, which utlizes a multi-attribute auction protocol in order to deal with both a price and a CO2 emission rate. Experimental results show that collaboration among entities through the market provides a more profitable plan for each entity and abatement of CO2 emission is also achieved. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(4): 54–63, 2008; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/eej.20418 [ABSTRACT FROM AUTHOR]

This paper provides comparisons of a variety of time-series methods for short-run forecasts of the main greenhouse gas, carbon dioxide, for the United States, using a recently released state-level data set from 1960–2001. We test the out-of-sample performance of univariate and multivariate forecasting models by aggregating state-level forecasts versus forecasting the aggregate directly. We find evidence that forecasting the disaggregate series and accounting for spatial effects drastically improves forecasting performance under root mean squared forecast error loss. Based on the in-sample observations we attempt to explain the emergence of voluntary efforts by states to reduce greenhouse gas emissions. We find evidence that states with decreasing per capita emissions and a “greener” median voter are more likely to push toward voluntary cutbacks in emissions. [ABSTRACT FROM AUTHOR]

Pincer ligated coordination complexes of base metals have shown remarkable catalytic activity for hydrogenation/dehydrogenation of CO2. The recently reported MeN[CH2CH2(iPr2)]2Co(I)PNP‐pincer complex was shown to exhibit substantially higher catalytic activity in comparison to the corresponding catalyst, HN[CH2CH2(iPr2)]2Co(I)PNP, bearing a secondary nitrogen center on the pincer ligand. Here, we computationally investigate the mechanisms for hydrogenation of CO2 to formate catalyzed by these two Co‐PNP complexes to explain how such a small structural difference could have a sizable impact on their catalytic activity. Plausible hydrogenation routes were examined in details and our findings provide solid support for the experimental observations. Our results reveal that such trends in catalytic activity could be explained from the lower activation barrier for the hydride transfer step upon changing the pincer nitrogen center from secondary to tertiary. [ABSTRACT FROM AUTHOR]

The photocatalytic reduction of CO2 into fuels offers the prospect for creating a new CO2 economy. Harnessing visible light‐driven CO2‐to‐CO reduction mediated by the long‐lived triplet excited state of rhenium(I) tricarbonyl complexes is a challenging approach. We here develop a series of new mononuclear rhenium(I) tricarbonyl complexes (Re‐1−Re‐4) based on the imidazole‐pyridine skeleton for photo‐driven CO2 reduction. These catalysts are featured by combining pyridyl‐imidazole with the aromatic ring and different pendant organic groups onto the N1 position of 1,3‐imidazole unit, which display phosphorescence under Ar‐saturated solution even at ambient conditions. By contrast, {Re[9‐(pyren‐1‐yl)‐10‐(pyridin‐2‐yl)‐9H‐pyreno[4,5‐d]imidazole)](CO)3Cl} (Re‐4) by introducing pyrene ring at the N1 position of pyrene‐fused imidazole unit exhibits superior catalytic performance with a higher turnover number for CO (TONCO=124) and >99.9 % selectivity, primarily ascribed to the strong visible light‐harvesting ability, long‐lived triplet lifetimes (164.2 μs) and large reductive quenching constant. Moreover, the rhenium(I) tricarbonyl complexes derived from π‐extended pyrene chromophore exhibit a long lifetime corresponding to its ligand‐localized triplet state (3IL) evidenced from spectroscopic investigations and DFT calculations. [ABSTRACT FROM AUTHOR]

Recent years have seen a growing interest in metal‐free CO2 activation by silylenes, silylones, and silanones. However, compared to mononuclear silicon species, CO2 reduction mediated by dinuclear silicon compounds, especially disilynes, has been less explored. We have carried out extensive computational investigations to explore the mechanistic avenues in CO2 reduction to CO by donor‐stabilized disilyne bisphosphine adduct (R1M) and phosphonium silaylide (R2) using density functional theory calculations. Theoretical calculations suggest that R1M exhibits donor‐stabilized bis(silylene) bonding features with unusual Si−Si multiple bonding. Various modes of CO2 coordination to R1M have been investigated and the coordination of CO2 by the carbon center to R1M is found to be kinetically more facile than that by oxygen involving only one or both the silicon centers. Both the theoretically predicted reaction mechanisms of R1M and R2‐mediated CO2 reduction reveal the crucial role of silicon‐centered lone pairs in CO2 activations and generation of key intermediates possessing enormous strain in the Si−C−O ring, which plays the pivotal role in CO extrusion. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and conversion of CO2 into materials (IC3M) is an attractive solution to meet global energy demand, reduce our dependence on fossil fuels, and lower CO2 emissions. Herein, using a water‐lean post‐combustion capture solvent, [N‐(2‐ethoxyethyl)‐3‐morpholinopropan‐1‐amine] (2‐EEMPA), >90 % conversion of captured CO2 to hydrocarbons, mostly methane, is achieved in the presence of a heterogenous Ru catalyst under relatively mild reaction conditions (170 °C and <15 bar H2 pressure). The catalytic performance was better in 2‐EEMPA than in aqueous 5 m monoethanol amine (MEA). Operando nuclear magnetic resonance (NMR) study showed in situ formation of N‐formamide intermediate, which underwent further hydrogenation to form methane and other higher hydrocarbons. Technoeconomic analyses (TEA) showed that the proposed integrated process can potentially improve the thermal efficiency by 5 % and reduce the total capital investment and minimum synthetic natural gas (SNG) selling price by 32 % and 12 %, respectively, compared to the conventional Sabatier process, highlighting the energetic and economic benefits of integrated capture and conversion. Methane derived from CO2 and renewable H2 sources is an attractive fuel, and it has great potential as a renewable hydrogen carrier as an environmentally responsible carbon capture and utilization approach. [ABSTRACT FROM AUTHOR]

The development of effective catalysts for the electrocatalytic carbon dioxide reduction reaction (CO2RR) to two‐carbon (C2) products is a practical approach to solve the energy crisis and stabilize the carbon cycle of the ecosystem. The production of electrocatalytic CO2RR with copper metal shows low selectivity and mainly generates one‐carbon (C1) products, hindering its wide practical application. The use of copper (I) oxide (Cu2O) in electrocatalysis has attracted intense research attention because it can more efficiently produce C2 products with high energy density such as ethylene (C2H4) and ethane (C2H6). We use an amino‐modified Cu2O catalyst (NH2−Cu2O) for electrocatalytic CO2RR to obtain significantly increased production of the CO and C2 products. Electrochemical in‐situ infrared spectroscopy analysis was used to detect the presence of the *COOH and *CHO reaction intermediates. Density functional theory calculations showed that the amino (−NH2) modification reduces the free energy of the *CO→*CHO reaction that is the rate‐determining step in C2H4 production. Our results show that amino modification can promote the protonation of *CO and *CHO carbon‐carbon coupling to produce C2H4. Thus, amino‐modified copper‐based catalysts are promising materials for application in electrocatalytic CO2RR to multi‐carbon products. [ABSTRACT FROM AUTHOR]

The rapidly rising level of carbon dioxide in the atmosphere resulting from human activity is one of the greatest environmental problems facing our civilization today. Most technologies are not yet sufficiently developed to move existing infrastructure to cleaner alternatives. Therefore, techniques for capturing carbon dioxide from emission sources may play a key role at the moment. The structure of the UiO‐66 material not only meets the requirement of high stability in contact with water vapor but through the water pre‐adsorbed in the pores, the selectivity of carbon dioxide adsorption is increased. We successfully applied the recently developed methodology for water adsorption modelling. It allowed to elucidate the influence of water on CO2 adsorption and study the mechanism of this effect. We showed that water is adsorbed in octahedral cage and stands for promotor for CO2 adsorption in less favorable space than tetrahedral cages. Water plays a role of a mediator of adsorption, what is a general idea of improving affinity of adsorbate. On the basis of pre‐adsorption of methanol as another polar solvent, we have shown that the adsorption sites play a key role here, and not, as previously thought, only the interaction between the solvent and quadrupole carbon dioxide. Overall, we explained the mechanism of increased CO2 adsorption in the presence of water and methanol, as polar solvents, in the UiO‐66 pores for a potential post‐combustion carbon dioxide capture application. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs), as a novel emerging category in heterogeneous catalysis, have exhibited superb activity and selectivity within the scope of many catalytic reactions, originating from their nature of atomic dispersion. However, they are not appropriate for more complicated reactions that benefit from multi‐metal promotion, such as the carbon dioxide reduction reaction (CO2RR). Atomic pair catalysts can provide a synergistic effect to break the intrinsic activity limit. Herein, inspired by theoretical prediction, a hetero‐paired atomic‐site catalyst (Ni/Fe−N/O−C) was developed for CO2RR. Typically, the trace‐amount‐loaded double‐atom‐site catalysts exhibited outstanding turnover frequencies (≈460 s−1) surpassing reported ones by far. Interestingly, the loaded metal contents of the three M−N/O−C samples were extremely low, and Ni/Fe−N/O−C exhibited greatly improved durability compared with pure Ni−N/O−C or Fe−N/O−C and excellent CO selectivity above 80 % within a broad potential window of −1.4 to −1.7 V (vs. saturated calomel electrode, 99.8 % at −1.5 V). The superb performance of diatomic‐site catalysts was attributed to the adjusted local environment and electron structure of the active center, which could decrease the reaction barrier of *COOH formation. This work presents new insights into manipulating electrocatalytic performance for the development of more sophisticated active sites. [ABSTRACT FROM AUTHOR]

This work reports on the use of gallium aminotrisphenolate compounds as catalysts for the synthesis of cyclic carbonates from epoxides and CO2. The results show that they are highly active, and more so than the corresponding aluminium congeners. The catalyst system is applicable at low and elevated temperatures across a wide substrate scope including terminal, internal, multiple and fully deuterated epoxides. Applying low catalyst loadings has allowed for a TON of 344,000 to be obtained, highlighting their stability. A DFT investigation has confirmed that the gallium catalysts have lower energetic profiles compared to the aluminium congeners. Measurement of the Lewis acidity of both the gallium and aluminium aminotrisphenolate compounds using the Gutmann‐Beckett method provides the experimental proof that the gallium compounds are more Lewis acidic than their aluminium congeners. Finally, Ab‐Initio Molecular Dynamic (AIMD) simulations have investigated and quantified the dynamic behaviour of the catalytic systems, highlighting an important increase in fluxionality in some cases which helps to explain the increase in catalytic activity. [ABSTRACT FROM AUTHOR]