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Air has the advantage of abundance and easy availability, so it is suitable to be used as a synthetic raw material and energy source. However, the triggering of inert small molecules in the air, like O2, N2, and CO2, is a kinetically complex and energetically challenging multistep reaction. Photocatalysis brings hope for this challenge, but obstacles remain in many aspects. Here, aiming at the key difficulties of the photocatalytic activation and conversion of these three inert small molecules, i.e., regulating electronic structure, active sites, charge carrier separation and mobility, and reaction energy barrier, we propose the concept of functional customization strategy of ultrathin two-dimensional materials for achieving more efficient activation and better performance, including thickness control, vacancy engineering, doping operation, single-atom site fabrication, and composite construction. The in-depth understanding of the functional customization will provide more profound guidance for designing photocatalysts that specialize in activating and converting inert small molecules.

There may be trade‐offs in the allocation patterns of recent photosynthetic carbon (RPC) allocation in response to environmental changes, with a greater proportion of RPC being directed towards compartments experiencing limited resource availability. Alternatively, the allocation of RPC could shift from sources to sinks as plants processing excess photosynthates. It prompts the question: Does the pattern of RPC allocation vary under global changes? If so, is this variation driven by optimal or by residual C allocation strategies? We conducted a meta‐analysis by complicating 273 pairwise observations from 55 articles with 13C or 14C pulse or continuous labeling to assess the partitioning of RPC in biomass (leaf, stem, shoot, and root), soil pools (soil organic C, rhizosphere, and microbial biomass C) and CO2 fluxes under elevated CO2 (eCO2), warming, drought and nitrogen (N) addition. We propose that the increased allocation of RPC to belowground under sufficient CO2 results from the excretion of excess photosynthates. Warming led to a significant reduction in the percentage of RPC allocated to shoots, alongside an increase in roots allocation, although this was not statistically significant. This pattern is due to the reduced water availability resulting from warming. In conditions of drought, there was a notable increase in the partitioning of RPC to stems (+7.25%) and roots (+36.38%), indicative of a greater investment of RPC in roots for accessing water from deeper soil. Additionally, N addition led to a heightened allocation of RPC in leaves (+10.18%) and shoots (+5.78%), while reducing its partitioning in soil organic C (−8.92%). Contrary to the residual C partitioning observed under eCO2, the alterations in RPC partitioning in response to warming, drought, and N supplementation are more comprehensively explained through the lens of optimal partitioning theory, showing a trade‐off in the partitioning of RPC under global change. [ABSTRACT FROM AUTHOR]

The potential would be an important issue for enhancing photocatalytic HER and CO 2 photoreduction selectivity. Herein, the Co 3 O 4 /Ti3+-TiO 2 hollow S-scheme heterojunction is fabricated via continuous light modification-chemical-annealing-reduction method. Evaluated by photocatalytic performance, the as-prepared Co 3 O 4 /Ti3+-TiO 2 hollow S-scheme heterojunction exhibits remarkable photocatalytic performance enhancement than single TiO 2 , including hydrogen evolution (∼396.16 μmol/g·h, ∼15 folds) and CO 2 photoreduction (H 2 /CH 4 /CO: ∼20.32/80.57/9.85 μmol/g·h, ∼20 folds), and achieves CO 2 photoreduction to CH 4 selectivity enhancement, which can be mainly ascribed to the synergism of Ti3+/O v and S-scheme heterojunction. There, Ti3+/O v can not only increase the solar efficiency, but also decrease the energy barrier of H+ and ∗CO photoreduction to enhance HER and CO 2 to CH 4 selectivity, including promote the H+ diffusion and CO 2 absorption. Additionally, the formed Co 3 O 4 /Ti3+-TiO 2 S-scheme heterojunction can promote the photo-generated carrier separation/transportation. Also, the hollow 3D structure obtained by ZIF-67 self-template can increase solar efficiency and stability. [Display omitted] • Ti3+/O v can decrease ∗CO photoreduction energy barrier to enhance CH 4 selectivity. • Ti3+/O v with shallow donor level can increase carrier concentration. • Heterojunction can promote carriers separation/transport via appropriate potential. • Hollow 3D structure can increase interface heterojunction and stability. • ZIF-67 self-template can decrease photocatalyst corrosion. [ABSTRACT FROM AUTHOR]

Solar-induced chlorophyll fluorescence (SIF) has a high correlation with Gross Primary Production (GPP). However, studies focusing on the impact of drought on the SIF-GPP relationship have had mixed results at various scales, and the mechanisms controlling the dynamics between photosynthesis and fluorescence emission under water stress are not well understood. We developed a leaf-scale measurement system to perform concurrent measurements of active and passive fluorescence, and gas-exchange rates for winter wheat experiencing a one-month progressive drought. Our results confirmed that: (1) shifts in light energy allocation towards decreasing photochemistry (the quantum yields of photochemical quenching in PSII decreased from 0.42 to 0.21 under intermediate light conditions) and increasing fluorescence emissions (the quantum yields of fluorescence increased to 0.062 from 0.024) as drought progressed enhance the degree of nonlinearity of the SIF-GPP relationship, and (2) SIF alone has a limited capacity to track changes in the photosynthetic status of plants under drought conditions. However, by incorporating the water stress factor into a SIF-based mechanistic photosynthesis model, we show that drought-induced variations in a variety of key photosynthetic parameters, including stomatal conductance and photosynthetic CO2 assimilation, can be accurately estimated using measurements of SIF, photosynthetically active radiation, air temperature, and soil moisture as inputs. Our findings provide the experimental and theoretical foundations necessary for employing SIF mechanistically to estimate plant photosynthetic activity during periods of drought stress. [ABSTRACT FROM AUTHOR]

The preparation of methanol chemicals through CO2 and H2 gas is a positive measure to achieve carbon neutrality. However, developing catalysts with high selectivity remains a challenge due to the irreversible side reaction of reverse water gas shift (RWGS), and the low-temperature characteristics of CO2 hydrogenation to methanol. In-plane sulfur vacancies of MoS2 can be the catalytic active sites for CH3OH formation, but the edge vacancies are more inclined to the occurrence of methane. Therefore, MoS2 and a series of MoS2/Nix and MoS2/Cox catalysts doped with different amounts are prepared by a hydrothermal method. A variety of microscopic characterizations indicate that Ni and Co doping can form NiS2 and CoS2, the existence of these substances can prevent CO2 and H2 from contacting the edge S vacancies of MoS2, and the selectivity of the main product is improved. DFT calculation illustrates that the larger range of orbital hybridization between Ni and MoS2 leads to CO2 activation and the active hydrogen is more prone to surface migration. Under optimized preparation conditions, MoS2/Ni0.2 exhibits relatively good methanol selectivity. Therefore, this strategy of improving methanol selectivity through metal doping has reference significance for the subsequent research and development of such catalysts. [ABSTRACT FROM AUTHOR]

Decreasing particle size (like thickness) is a common strategy to enhance the activities of catalysts. In this work, we have synthesized two coppers, which are bismuth-based metal-organic framework (CuBi-MOF) catalysts with different thicknesses (134.8 and 2.0 nm). In contrast to common expectations, large thickness CuBi-MOF has exhibited superior activities as a comparison to its small-thickness counterpart in terms of carbon dioxide electroreduction to produce formate, characteristic of high selectivity (Faraday efficiency >90%), a wide window of potential (-0.6 to -1.6 V vs. reversible hydrogen electrode), and large current densities (up to -380mAcm-2). The mechanism study has been performed by using density functional theory calculations, which highlight the strong synergic effect between Cu and Bi sites in large-thickness CuBi-MOF for activating CO2 molecules. Consequently, large-thickness CuBi-MOF could show smaller Gibbs free energies compared to its small counterpart for binding with reaction intermediate (*COOH, 1.1 vs. 1.8 eV). The result of this work could provide new insights into catalyst design toward a number of electrochemical systems. [ABSTRACT FROM AUTHOR]

Summary: The greater duckweed (Spirodela polyrhiza 7498) exhibits trophic diversity (photoautotrophic, heterotrophic, photoheterotrophic, and mixotrophic growth) depending on the availability of exogenous organic carbon sources and light.Here, we show that the ability to transition between various trophic growth conditions is an advantageous trait, providing great phenotypic plasticity and metabolic flexibility in S. polyrhiza 7498.By comparing S. polyrhiza 7498 growth characteristics, metabolic acclimation, and cellular ultrastructure across these trophic modes, we show that mixotrophy decreases photosynthetic performance and relieves the CO2 limitation of photosynthesis by enhancing the CO2 supply through the active respiration pathway. Proteomic and metabolomic analyses corroborated that S. polyrhiza 7498 increases its intracellular CO2 and decreases reactive oxygen species under mixotrophic and heterotrophic conditions, which substantially suppressed the wasteful photorespiration and oxidative‐damage pathways. As a consequence, mixotrophy resulted in a higher biomass yield than the sum of photoautotrophy and heterotrophy.Our work provides a basis for using trophic transitions in S. polyrhiza 7498 for the enhanced accumulation of value‐added products. [ABSTRACT FROM AUTHOR]

We developed an approach to realize the comprehensive utilization of CO2 and glycerol by smartly design a nanocatalyst, which concerns the coupling of catalytic reactions and the separation or capture process. Specifically, MgFe‐CO32−‐LDHs with different thickness were fabricated by employing atmospheric CO2 as carbon source and an atomic‐level interface was constructed by introducing Pt single atoms to obtain series of Pt/MgFe‐LDHs nanocatalysts. During a catalytic assessment, the CO32− confined within interlayer was in situ converted when integrated with glycerol oxidation under irradiation. The optimal nanocatalyst exhibited a decent conversion efficiency of CO32−‐CO‐CH4 and near 100% selectivity of secondary hydroxy group in glycerol. DFT calculation, isotope‐labeled experiments and in situ spectrograph characterization revealed possible coupling reaction mechanism. More importantly, the nanocatalyst exhibited impressive reusability for at least six 6 runs. The developed multiple coupling process will be an alternative and promising procedure for the waste and low‐valued sources synergetic utilization. [ABSTRACT FROM AUTHOR]

One mononuclear Mn(III) complex [MnIIIL(H2O)(MeCN)](ClO4) (1) and one hetero-binuclear complex [(CuIILMnII(H2O)3)(CuIIL)2](ClO4)2·CH3OH (2) have been synthesized with the Schiff base ligand (H2L = N,N′-bis(3-methoxysalicylidene)-1,2-phenylenediamine). Single crystal X-ray structural analysis manifests that the Mn(III) ion in 1 has an octahedral coordination structure, whereas the Mn(II) ion in 2 possesses a trigonal bipyramidal configuration and the Cu(II) ion in 2 is four-coordinated with a square-planar geometry. Electrochimerical catalytic investigation demonstrates that the two complexes can electrochemically catalyze water oxidation and CO2 reduction simultaneously. The coordination environments of the Mn(III), Mn(II), and Cu(II) ions in 1 and 2 were provided by the Schiff base ligand (L) and labile solvent molecules. The coordinately unsaturated environment of the Cu(II) center in 2 can perfectly facilitate the catalytic performance of 2. Complexes 1 and 2 display that the over potentials for water oxidation are 728 mV and 216 mV, faradaic efficiencies (FEs) are 88% and 92%, respectively, as well as the turnover frequency (TOF) values for the catalytic reduction of CO2 to CO are 0.38 s−1 at −1.65 V and 15.97 s−1 at −1.60 V, respectively. Complex 2 shows much better catalytic performance for both water oxidation and CO2 reduction than that of complex 1, which could be owing to a structural reason which is attributed to the synergistic catalytic action of the neighboring Mn(III) and Cu(II) active sites in 2. Complexes 1 and 2 are the first two compounds coordinated with Schiff base ligand for both water oxidation and CO2 reduction. The finding in this work can offer significant inspiration for the future development of electrocatalysis in this area. [ABSTRACT FROM AUTHOR]

CO2 methanation is one of the vital reactions to utilize CO2 and realize power to gas process. To decrease the CO2 capture cost and alleviate the hot spots during the strong exothermic methanation reaction, here, we report a coupling of CO2 capture process with in situ CO2 methanation process through a ceramic‐molten carbonate (MC) dual phase membrane reactor over the Ni‐based catalyst. The performance of the membrane reactor was systematically investigated and compared with the traditional fixed‐bed reactor. The results show that the performance of the membrane reactor is higher than that of the fixed‐bed reactor, since the produced steam through the methanation process can be partially removed through the dual‐phase membrane, which promotes the reaction shift to right side. A stability test shows no obvious degradation within 32 h. These results indicate that the membrane reactor is promising for coupling CO2 capture with in situ methanation process. [ABSTRACT FROM AUTHOR]

A micro-pulse lidar system incorporating differential absorption lidar (DIAL) and coherent Doppler wind lidar (CDWL) is proposed and demonstrated. Due to the high signal-to-noise ratio (SNR) of the superconducting nanowire single-photon detector (SNSPD), the DIAL channel achieves high sensitivity in CO2 measurement. Meanwhile, the CDWL channel is used to obtain the horizontal wind field. In the process of the optimization and calibration of the DIAL receiver, specifically, mode scrambling and temperature control of the connecting fiber between the telescope and the SNSPD enhance the stability and robustness of the system. Horizontal scanning of the CO2 concentration and the wind field is carried out in a 6 km range over a scanning span of 60° with a radial resolution of 150 m and 15 s. The results show that the hybrid lidar system captures the spatial distribution of CO2 concentration and the wind field simultaneously. The horizontal net CO2 flux in a radius of 6 km is estimated by integrating the CO2 concentration and the wind transport vector, indicating different characteristics of horizontal net CO2 fluxes in an industrial area, a university campus, and a park. During most of the experiment, CO2 flux remained positive in the industrial area, but balances fell to nearly zero on the campus and in the park. The horizontal net fluxes averaged over 24 h in the three areas are 3.5 × 105 ppm·m2·s−1, 0.7 × 105 ppm·m2·s−1, and 0.1 × 105 ppm·m2·s−1. [ABSTRACT FROM AUTHOR]

The CO2 reduction reaction (CRR) represents a promising route for the clean utilization of renewable resources. But mass‐transfer limitations seriously hinder the forward step. Enhancing the surface hydrophobicity by using polymers has been proved to be one of the most efficient strategies. However, as macromolecular organics, polymers on the surface hinder the transfer of charge carriers from catalysts to reactants. Herein, we describe an in‐situ surface fluorination strategy to enhance the surface hydrophobicity of TiO2 without a barrier layer of organics, thus facilitating the mass transfer of CO2 to catalysts and charge transfer. With less obstruction to charge transfer, a higher CO2, and lower H+ surface concentration, the photocatalytic CRR generation rate of methanol (CH3OH) is greatly enhanced to up to 247.15 μmol g−1 h−1. Furthermore, we investigated the overall defects; enhancing the surface hydrophobicity of catalysts provides a general and reliable method to improve the competitiveness of CRR. [ABSTRACT FROM AUTHOR]

• Fractal polyhedral MOFs (Cu-TATB) is synthesized for CO 2 /N 2 separation. • Small-sized pores can capture CO 2 , while large-sized pores facilitate N 2 escape. • Different sized channels successfully achieving the goal of gas separation. A fractal polyhedral pore structural MOFs (Cu-TATB) is synthesized from the coordination of tridentate ligands (H 3 TATB) and Cu 4 clusters. This material is characterized by single crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis. The structure contains two different pore structures, including closed octahedral cages and open tetrakaidecahedron cages. The material has been successfully utilized for the separation of CO 2 /N 2 due to the fractal structure of the channel with different pore sizes. Under optimized temperature, Cu-TATB adsorbed a large amount of CO 2 and only negligible amount of N 2 , and the selectivity reaches 27. Breakthrough experiments demonstrated that this material can efficiently separate N 2 and CO 2. This structure further demonstrates the infinite potential of 3D MOFs with diverse pore structures in applications such as CO 2 adsorption and separation. [ABSTRACT FROM AUTHOR]

• First accounting of CO 2 mineralization and utilization potential of tailings sand at the ownership scale in China. • Innovative ARIMA-cloud model predicted tailings sand production and consumption. • Analyzed carbon sinks under scenarios of technological leapfrog and elevated utilization. • Screened potential spatial clusters of mineralized carbon sinks from tailings sand. • The feasibility of mineralization project layouts was judged by enterprise size. The use of tailings sand for CO 2 mineralization and utilization (CMU) has been emerging globally, offering a sustainable solution for repurposing tailings sand while establishing a stable carbon sink. Despite several reports that evaluated process performance and project benefits, existing research has not delved into the project layout focusing on the tailings pond facility and the feasibility considerations from a cluster and ownership perspective. Conducting facility-scale refined mineralized carbon sink (MCS) and layout feasibility assessment is a key issue that needs to be addressed urgently. Here, we accounted for CMU potential (CMUP) of tailings sand using a sample of 6219 tailings pond ownerships in China, predicted future annual carbon sinks through an innovative ARIMA-cloud model, and analyzed the feasibility of project layouts within potential clusters concerning enterprise size. Our results indicate that the CMUP of accumulated tailings sand in China amounts to 1817.87 Mt. In a combined scenario involving future technological leapfrogging and increased utilization, the average annual carbon sink by 2030 is projected to be 24.73 Mt. A considerable reduction in project layout feasibility across all scenarios was observed due to the mismatch between carbon clusters and enterprise size. Our study reveals that CMU using tailings sand should be regarded as one of the essential green technologies in the portfolio of strategic Chinese CO 2 mitigation. However, we highlight the necessity of aligning cluster programs with the support capacity of the ownership enterprise to ensure the optimal project success. [Display omitted] [ABSTRACT FROM AUTHOR]

Calcium looping cycle integrated CO 2 capture and conversion (CaL-ICCC) is a promising technology for addressing energy and environmental issues related to anthropogenic CO 2 emissions. This technology offers high efficiency, low cost, and enhanced safety, as it eliminates the need for purification, compression, transportation, and storage processes. To achieve integrated CO 2 capture and conversion (ICCC), the development of new and highly efficient catalysts is crucial. Dual functional materials (DFMs), which consists of absorbents and catalysts, playing a key role in bridging this gap. Recently, DFMs have garnered considerable attention, with a focus on the development of efficient, selective, and stable catalysts. This review summarizes the current advancements in metal oxide-doped CaO-based sorbents and metal oxide-supported catalytic conversion of CO 2 in the reverse gas shift reaction (RWGS), specifically in terms of absorbent and catalyst performance, selectivity, and stability. Additionally, the mechanism of CaO-based CO 2 capture and in-situ conversion in CaL-RWGS processes is discussed. The challenges and future prospects in terms of material stability and durability, technological and economic hurdles, dual functional material structures, and the application of AI technologies are also addressed. [Display omitted] • The performance of metal oxide doped CaO-based adsorbents were discussed. • The performance of metal oxide as supported in RWGS was discussed. • The mechanisms of absorbents and DFMs of CO 2 conversion were examined individually. • Potential future development trends were recommended in this work. [ABSTRACT FROM AUTHOR]

The projected rise in atmospheric CO 2 levels to 550 ppm by mid-century may reduce protein, iron, and zinc levels in certain cereal crops by 3–17 %. In China, staple foods provide nearly 50 % of total energy and 40 % of essential nutrients, and their cultivation exacerbates environmental stress; adjusting staple food consumption may bring environmental and health benefits. Using China Health and Nutrition Survey (CHNS) data, this study compared current staple food consumption (S BAU) to an optimized balanced diet scenario with the consumption of whole grains and legumes replaces excessive refined grains. Findings reveal that S BAU falls short of recommended nutrient intake (RNI), while the optimized scenario offsets the nutritional impact of the elevated CO 2 , exceeding 95 % of the RNI for zinc and iron from staple food. Additionally, transition to the optimized scenario also reduces greenhouse gas emissions and blue water consumption by 7 % and 39 %, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

For carbon dioxide concentration (XCO2) distribution, the improvement of spatial and temporal resolution is very important in some scientific studies (e.g., studies of the carbon cycle and assessment of carbon emissions based on top-down theory). However, carbon sniffing satellites based on passive theory (e.g., Gosat-2, OCO-2, and OCO-3) are susceptible to cloud and aerosol interference when the data are captured. Therefore, the data collected by carbon sniffing satellites have relatively low utilization, especially in some regions where data gaps exist. Here, we present the Carbon Dioxide Coverage (CDC) dataset, an innovative theory to obtain high spatial and temporal resolution maps of XCO2 distribution by combining spatial attributes and extracted temporal attributes from the GOSAT satellite series data. This theory is divided into the following three parts. Firstly, several background values in the raw GOSAT data were removed through data pre-processing, and for spatial attributes, GOSAT satellite data gap areas were filled by combining adjacent GOSAT data and empirical Bayesian kriging (EBK) theory in the study area. Secondly, for the temporal attributes, we constructed a time profile parameter library, based on the GOSAT data of the time series to extract the temporal parameters from a specific formula at each point of the study area. Finally, for the integration of temporal and spatial information, based on the GOSAT satellite data and the populated data based on spatial attributes, we assign the temporal parameter information from the time parameter library to each pixel location in the study area, combining the transfer component analysis (TCA) theory, and then combine the assigned parameters with specific formulas to complete the prediction of XCO2 distribution. For temporal resolution, both the GOSAT_FTS_L3_V2.95 and CDC datasets are monthly-averaged resolution datasets from 2010 to 2020. And for spatial resolution, the CDC dataset is 0.25° resolution with a significant improvement compared to GOSAT_FTS_L3_V2.95 which is 2.5° resolution. And the dataset contained 136 files. Besides, for the data validation part, we used OCO-2 satellite data from 2009 to 2020 and TCCON data at mid and low latitudes, respectively. This CDC dataset and the original data from the TCCON sites were compared on a monthly-averaged scale. And the results showed that R2 was 0.9686, and RMSE was 1.3811 ppm. We also derived statistical monthly averaged XCO2 from OCO-2 data and compared it with the data set from our theory. And our evaluation index R was greater than 0.7, by comparison with OCO-2 during 2014-2020. Finally, to assess the accuracy of the algorithm, we compared the predicted results with the input data for the period of 2009-2020. And the comparison results show that the mean value of R2 is 0.93 and the mean value of RMSE is 0.53 ppm during 2010-2020. Data gaps produced by sniffer satellites are disturbed by factors such as clouds and aerosols and can be filled by this mapping technique is mentioned in this paper. This technique improves the utilization of XCO2 and the accuracy and resolution of the CDC dataset is sufficient for scientific applications. And the CDC dataset is publicly available at https://doi.org/10.6084/m9.figshare.17826404.v4 (Zhang et al., 2022), which is of significance for a multitude of scientific carbon research. [ABSTRACT FROM AUTHOR]

Atomically dispersed metal catalysts have been widely used in electrocatalysis because of their outstanding catalytic activity and high atomic utilization efficiency. As an extension of single‐atom catalysts (SACs), dual‐atom catalysts (DACs) provide new insights for the development of atomic‐scale catalysts. Higher metal loading and more flexible active sites endow DACs with improved catalytic performance as well as optimized reaction mechanism model. In this review, DACs are firstly classified according to their configurations and metal sites. Subsequently, the synthetic strategies and characterization techniques of DACs are introduced. Furthermore, the applications of DACs are exemplified in various electrocatalytic reactions, including oxygen reduction reaction, oxygen evolution reaction and carbon dioxide reduction reaction. Finally, the prospects to be expected and challenges to be faced with are discussed. [ABSTRACT FROM AUTHOR]

We investigate herein the reaction mechanism of dry reforming of methane over Pt clusters in combination with kinetic measurements and in-situ characterizations, proposing that the undissociated CO 2 involves in C-H bond activation and the direct reaction between CO 2 * and CH 4 * is considered as the kinetically relevant step. [Display omitted] • CO 2 is probably undissociatively involved in the process of CH 4 activation over Pt/MgO. • A Langmuir-Hinshelwood model is established to explain the DRM reaction mechanism. • Rates of dry reforming of CH 4 are lower than those of CH 4 -O 2 and CH 4 -H 2 O due to different oxidation capacities. • The reaction between CH 4 * and CO 2 * to form HCOO* and CH 3 * is probably the RDS. We investigate here systematically C-H bond activation mechanism on Pt/MgO with O 2 , H 2 O and CO 2 , and find that dry reforming of CH 4 (DRM) experiences a weak activity compared with reforming or partial oxidation of CH 4. Pressure dependence shows negligible effect of CO determined within a broad CO pressure regime (<10 kPa at high-pressure CH 4 /CO 2 (20.3 kPa) and <0.3 kPa at low-pressure CH 4 /CO 2 (0.8 kPa)) and competitive adsorption between CH 4 and CO 2 (0.8 kPa), suggesting that CO 2 is involved in CH 4 activation as an entire molecule. Based on established Langmuir-Hinshelwood model, reaction between adsorbed CH 4 and CO 2 to yield formate and methyl species was kinetically relevant. Both CO 2 and CH 4 derivatives are the most abundant surface intermediates, being confirmed by in situ FTIR and quasi - in-situ XPS. The oxidizability of oxidant was quantitatively evaluated; CO 2 has the weakest oxidizability, probably making DRM less active. DRM is structure-sensitive with terrace site of Pt as active component. The influence of reverse water–gas shift was dominant in modifying selectivity. This work will certainly reconcile contradictories on CH 4 activation mechanism and push the industrial application of CH 4 forward. [ABSTRACT FROM AUTHOR]

The significance of converting CO 2 into valuable feedstock is highly emphasized with the carbon neutrality vision. Generally, CO and H 2 are usually applied as the protective gases during CO 2 electrolysis in nickel based Solid Oxide Electrolysis Cell (SOEC). In this paper, the effects of H 2 and CO as protective gases on the performance of a Ni-YSZ (yttria stabilization zirconia) based SOEC are studied. The electrode processes of the cell are investigated by the electrochemical impedance spectroscopy (EIS) and calculated distribution of relaxation times (DRT) results. The results show that CO makes little difference on the performance of the cell while the cell shows a superior performance with H 2 as protective gas, indicating different mechanisms behind. The distinct discrepancies in characteristic frequency ranges of electrode processes with the CO 2 –CO and CO 2 –H 2 mixtures show that the replacement of CO by H 2 changes the reduction pathway of CO 2 from electrochemical reduction to thermochemical reduction, and only steam is electrolyzed. However, the direct injection of steam deteriorates slightly the performance of SOEC. The effect of reverse water gas shift (RWGS) reaction on the electrochemical performance of SOEC is explored and its effect of delaying the concentration polarization and extending the limiting current density is confirmed. Furthermore, the unique pattern of flattened j-V curve at high applied current of CO 2 electrolysis is repeatedly emphasized. • The performance of SOEC with H 2 as protective gas was superior compared to that with CO. • The existence of H 2 changed the reduction pathway of CO 2 from electrochemical reduction to thermochemical one. • The effect of RWGS reaction of extending the limiting current density was proved. • The unique pattern of flattened j-V curve at higher applied current of exclusive CO 2 electrolysis was emphasized. [ABSTRACT FROM AUTHOR]

[Display omitted] The current research on the CO 2 RR process mainly focuses on the high selectivity of a single product and the material selectivity in the path process [1], [2] Guo et al., 2019. There are relatively few studies on changes and causes. In this work, TiO 2 /TiO formed by in-situ oxidation was used as a photocatalyst for CO 2 reduction. The structure of this semiconductor/metal-like heterojunction makes the internal electric field appear in the catalyst, which greatly improves the activity of the photocatalytic reaction. During the test, it was found that the hydrogenation product gradually appeared in the reaction product due to the appearance of TiO 2. In the absence of a sacrificial agent, the catalyst exhibited a high HCOOH selectivity and obtained a considerable yield of 46.37 μmol g−1h−1. After adding the sacrificial agent triethanolamine (TEOA), TiO 2 /TiO showed good CO production ability. As the reaction progressed, CH 4 was gradually produced. DFT calculations confirmed that the structure of the heterojunction has lower workfunction for the CO 2 hydrogenation option, and the energy band at the contact position is curved. The construction of this system has guiding significance for the construction of light-driven CO 2 hydrogenation products in the future. [ABSTRACT FROM AUTHOR]

• (1-x)ZnO + xNa 2 CO 3 (x = 0, 0.5, 1.0, 1.5 mol%) varistor ceramics were fabricated via the solid-state sintering technique at a low sintering temperature of 900 ℃. • The Na 2 CO 3 additive markedly reduced the donor density and interface state density. However, it increased the barrier height, thereby enhancing the switching field, breakdown strength, and the nonlinear coefficient. • The dielectric constant of varistor ceramic decreased with increasing Na 2 CO 3 concentrations because that the dielectric constant is proportional to the ratio of the average grain size to the depletion layer width. Herein, (1-x)ZnO + xNa 2 CO 3 (x = 0, 0.5, 1.0, and 1.5 mol%) varistor ceramics were prepared via conventional solid-state sintering at a low sintering temperature of 900 ℃. The microstructure and electrical properties of these varistor ceramics were systematically investigated as a function of Na 2 CO 3 concentration. Results revealed that the prepared varistor ceramics exhibit the hexagonal structure without a secondary phase. The increase of Na 2 CO 3 concentration promotes the ZnO grain growth. Owing to an increasement in the barrier height at the grain boundaries, the nonlinear electrical properties of the ceramics considerably improve with increasing Na 2 CO 3 concentration. The optimal composition of 98.5 mol%ZnO + 1.5 mol%Na 2 CO 3 corresponds to a nonlinear coefficient of 3.55, leakage current density of 450 μA/cm2, breakdown strength of 241.2 V/mm, and barrier height of 0.57 eV. Moreover, the dielectric properties of the varistor ceramics are considerably affected by Na 2 CO 3 concentration. [ABSTRACT FROM AUTHOR]

The surface environment plays an indispensable role in the electrocatalysis of the CO 2 reduction reaction (CO 2 RR). Being one of the V-shaped nanotwins, the Cu ∑3(111) nanotwin boundary (NTB) features two junctions of NTB with the (111) surface, designated as the summit and valley, leading to more relaxed structural fields. In contrast to the ideal Cu (111) surface, the d -band center of Cu situated on the summit position of 6NTB is shifted to the Fermi level by 0.11 eV, thus modifying the adsorption capacity. Sequentially, the CO dimerization is strongly focused on the summit position (01–02 site pair), revealing a synergistic effect. The mechanism provides an explanation for the detection of eight possible C-C coupling pathways. Furthermore, these findings disclose dissimilarities in the activity of Cu (111) and NTB-(111) with respect to C 2 products, and provide new ideas for the mechanistic studies of the copper-catalyzed CO 2 RR. [Display omitted] [ABSTRACT FROM AUTHOR]

The production of value‐added chemicals from CO2 electroreduction, using renewable energy, provides an appealing route to achieve the goal of carbon neutrality. Challenges remain in designing and understanding of high‐performance catalysts with restructuring behavior under electrochemical conditions. Here, the intrinsic performance enhancement of an Au‐complex derived carbon nanotube‐supported Au nanoclusters catalyst was demonstrated for CO2 reduction. This catalyst exhibited impressive activity for yielding CO in both H‐cell and flow cell reactors. Experimental results revealed that the synthesis procedure via metal complex reconstructing on proper support induced charge transfer between Au nanoclusters and carbon nanotubes, forming a rather electron‐rich state for Au active sites, which greatly contributed to the CO2 activation pathway. [ABSTRACT FROM AUTHOR]

Microbial electrosynthesis is a biocathode-driven process, where autotrophic microorganisms can directly absorb electrons from the cathode or indirectly absorb electrons through H2 as energy to reduce CO2 to chemicals. In order to study the effect of surfactants on the performance of microbial electrosynthesis, transgenic Clostridium ljungdahlii was used as the strain, the non-ionic surfactant polyethylene glycol was used as the research object, and its addition amount was optimized. Results show that the performance of polyethylene glycol at 1. 0% was the best. The concentrations of acetate and butyrate were (0. 73±0. 11) and (0. 18±0. 01) g/L, respectively, which were 1. 58 times and 1. 21 times that of the control group. The addition of 4% polyethylene glycol inhibited microbial growth, resulting in lower acetate and butyrate. Scanning electron microscope and electrochemical analysis results show that 1. 0% polyethylene glycol promoted microbial adhesion on the electrode, and the electrocatalytic activity was also the highest. Furthermore, hydrogen evolution performance and reduction equivalent test results show that the 1. 0% polyethylene glycol had the highest hydrogen content during the experiment, and had the highest reduction equivalent, which was conducive to the conversion of carbon dioxide to acetate and butyrate. Our findings provide a direction to improve the election transfer rate in microbia electrosythesis. [ABSTRACT FROM AUTHOR]

Experimental and theoretical insights into robust PIL-Br@ZIF-8 hetero-frameworks for the selective conversion of CO 2 into cyclic carbonates under mild conditions. [Display omitted] • A novel strategy is developed for fabricating core–shell PILs@ZIF-8 composites. • PIL-Br@ZIF-8 enables simultaneous adsorption and activation of CO 2 and epoxide. • Low-concentration/low-pressure CO 2 conversion into cyclic carbonates was achieved. • PIL-Br@ZIF-8 is recyclable and exhibits good thermal and structural stability. • Valuable insight into the cycloaddition mechanism is theoretically elucidated. The present study, for the first time, reports the fabrication of core–shell poly(ionic liquids)@ZIF-8 nanocomposites through a facile in-situ polymerization strategy. These composites exhibited exceptional structural characteristics including high specific surface areas and the integration of high-density Lewis acid/base and nucleophilic active sites. The structure–activity relationship, reusability, and versatility of the poly(ionic liquids)@ZIF-8 composites were investigated for the cycloaddition reaction between CO 2 and epoxide. By optimizing the composites structures and their catalytic performance, PIL-Br@ZIF-8(2:1) was identified as an exciting catalyst that exhibits high activity and selectivity in the synthesis of various cyclic carbonates under mild or even atmospheric pressure or simulated flue gas conditions. Moreover, the catalyst demonstrated excellent structural stability while maintaining its catalytic activity throughout multiple usage cycles. By combining DFT calculations, we investigated the transition states and intermediate geometries of the cycloaddition reaction in different coordination microenvironments, thereby proposing a synergistic catalytic mechanism involving multiple active sites. [ABSTRACT FROM AUTHOR]

The conversion of CO 2 into useable energy materials through photocatalytic reactions has attracted much attention. In this paper, 2D BiOIO 3 /rod-shaped Zn-MOF type II heterojunction was constructed for efficient photocatalytic CO 2 reduction. XRD, SEM, TEM, XPS, and photoelectrochemical characterization tests were used to investigate the physicochemical properties of the prepared photocatalysts. Under 300 W Xenon lamp without any sacrificial reagents, the composite material BiOIO 3 /Zn-MOF-15(BOIOZ-15) showed the best photocatalytic efficiency, with a CO generation rate of 58.82 μmol/g/h, which is 1.7 times that of BiOIO 3. The formation of a type II heterojunction between BiOIO 3 and Zn-MOF-15 reduced the photogenerated electron-hole pair compounding, enhanced the separation and transport of photogenerated carriers, and improved the photocatalytic reaction performance of the composites. BiOIO 3 /Zn-MOF possible photocatalytic mechanisms. [Display omitted] • The photocatalytic rate of BiOIO 3 /Zn-MOF-15 reduction to CO is 58.82 μmol/g/h, which is 1.7 times that of BiOIO 3. • BiOIO 3 /Zn-MOF-15 photocatalysts are successfully synthesized. • A type II heterojunction was formed between BiOIO 3 and Zn-MOF-15, which improved the photocatalytic reaction performance of the composite. [ABSTRACT FROM AUTHOR]

The accumulation of spent LiFePO 4 is forming a "Li mine" in urban areas. Those "resources" not only cause waste of metal species but also seriously pollute the environment. The pursuit of a clean recycling way with minimized chemicals and secondary wastes has long been researched to close the supply chain of strategic elements such as Li. This research presents a straightforward and effective electrochemical method for the recovery of the spent LiFePO 4 by electrochemically oxidizing LiFePO 4 into FePO 4 while releasing Li+ into Na 2 CO 3 solution and collecting Li 2 CO 3 in one step without using acids. The conversion of LiFePO 4 to FePO 4 is realized by anodic oxidation, and the leaching efficiency of Li reaches more than 98%. Overall, the electrochemical-assisted method is a promising clean recycling method that even could use the surplus energy of spent batteries to drive the recovery process with reduced environmental footprints. [Display omitted] • LiFePO 4 was electrochemically leached in 0.5 M Na 2 CO 3 solution. • The leaching efficiency of Li was over 98%. • FePO 4 was directly recovered from the anode. • Li 2 CO 3 can be obtained by evaporating the electrolyte in one step. • The conductive carbon in the cathode materials can be reused. [ABSTRACT FROM AUTHOR]

Toluene, dichloromethane, and methanethiol were selected as probe molecules for aromatic, chlorinated, and sulfurated VOCs, respectively, to evaluate the catalytic properties of Pt/CeO 2 composites. The T 90 for toluene, DCM, and methanethiol oxidation were only 153, 265, and 240 °C, when 0.9 wt% Pt/CeO 2 was used as the catalyst. The synergy between Pt and support could be responsible for the high catalytic activity and antipoisoning properties. When combined with NDIR CO 2 sensors, the composite could be used for atmospheric total organic carbon detection. The recorded data almost overlap with that of the theoretical, suggesting the excellent reliability of the dictation system. The Pt/CeO 2 composite with abundant oxygen vacancies could use as a catalyst not only for VOCs elimination but also for atmospheric total organic carbon detection when combined with NDIR CO 2 sensors. [Display omitted] • The composites possess highly dispersed Pt species and abundant oxygen vacancies. • The 0.90% Pt/CeO 2 has the highest catalytic activities and excellent anti-poisoning properties. • The composite also could be used as catalyst for atmospheric total organic carbon detection. [ABSTRACT FROM AUTHOR]

Recorded information on marine sediments is affected by mineralization. In this study, we collected sediment samples from Bohai Bay, where human interference is typically high. Overall, the CO 2 fluxes in the columnar sediments decreased with increasing depth. The change in constants revealed a "C-curve" in which the mineralization rate first decreased significantly (i.e., from the 2020s to the 1980s) and subsequently increased slowly (i.e., from the 1980s to 1965). This may be explained by the fact that sediments from the 1980s–2020s were markedly influenced by the sedimentation rate, whereas sediments from the 1960s–1980s were predominantly influenced by microbial action. The loss of organic carbon due to mineralization accounted for approximately 15–20 % of the initial total organic carbon; therefore, when performing an inversion of the historical environment change using information derived from organic carbon in marine sediments, the influence of mineralization on this information should be fully considered. [Display omitted] • Exogenous input of organic carbon has higher CO 2 fluxes than organic carbon produced by marine organisms. • The mineralization rate constant of organic carbon in sediments of Bohai Bay in the past 50 years shows a "C"-type trend. • Mineralization significantly changed the trend of organic carbon in the sediments of Bohai Bay over the last 50 years. [ABSTRACT FROM AUTHOR]

• The different patterns of total resistance with current for different mixture were emphasized. • The causes for the different total resistance patterns were explored. • The electrode catalytic activity influenced significantly the activation resistance pattern. • The mechanism of co-electrolysis was explored based on the resistance patterns. • The contribution of electrochemical reduction of CO 2 to the production of CO was experimentally clarified. The reaction mechanism of co-electrolysis on the solid oxide electrolysis cells (SOEC) was widely discussed and no consensus had ever been reached. The performance of CO 2 electrolysis, H 2 O electrolysis and co-electrolysis was tested on an industrial-size cell with a conventional structure of Ni-YSZ|YSZ|GDC|LSCF. The co-electrolysis performance was inferior to that of H 2 O electrolysis but superior to that of CO 2 electrolysis. Also, the total resistance (R tot) of co-electrolysis first increased to a maximum and then began to descend with the increase of applied current, which was similar to the R tot pattern of CO 2 electrolysis but totally different from the monotonous increasing R tot pattern of H 2 O electrolysis. Study on a button cell with the same structure as the industrial-size cell showed that the catalytic activity of fuel electrode for H 2 O electrolysis was 9 times higher than that for CO 2 electrolysis and this huge difference might be the main cause of the different activation resistance (R act) and thus different R tot behavior of H 2 O electrolysis and CO 2 electrolysis. The appearance of R tot summit can be regarded as the signal of dominance of CO 2 electrochemical reduction during co-electrolysis. Based on the position of R tot summit and the impedance spectroscopy (EIS) results, the reaction mechanism of co-electrolysis was explored and it was found H 2 O electrolysis dominated at small current density and CO 2 electrolysis gradually occurred and dominated with the increase of current density. Besides, H 2 concentration in the inlet showed a more profound impact on the reaction mechanism of co-electrolysis compared to CO 2 concentration. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel photocatalytic material ZIF-8/Ag 2 CO 3 /CF was successfully prepared. • Ag 2 CO 3 enhance separation effect of photogenerated carriers. • Photocatalytic activity and stability of ZIF-8/Ag 2 CO 3 /CF composites are greatly improved. • Anchoring the Z-scheme ZIF-8/Ag 2 CO 3 photocatalyst on cotton fabric facilitates reusing. This paper presents a novel strategy for fabricating efficient, tailorable, and reusable photocatalytic cotton fabrics (CF) using the successive ionic layer adsorption and reaction (SILAR) method with Ag 2 CO 3 -doped zeolitic imidazolate framework-8 (ZIF-8) to degrade residual dyes from the textile industry. The Z-scheme photocatalytic degradation mechanism of ZIF-8/Ag 2 CO 3 /CF is also proposed. The results reveal that ZIF-8/Ag 2 CO 3 /CF prepared via 10 SILAR cycles photocatalytically degraded 91 % rhodamine B in 30 min. ZIF-8/Ag 2 CO 3 /CF had 15-fold higher photocatalytic activity than ZIF-8/CF. This enhancement was due to various effects, including, 1) the scattering of ZIF-8/Ag 2 CO 3 nanoparticles on the fiber surface rather than inducing agglomeration using the SILAR method, 2) the prevention of Ag 2 CO 3 photocorrosion by ZIF-8, and 3) the suppression of the recombination of photogenerated electrons and holes. Moreover, ZIF-8/Ag 2 CO 3 /CF maintained 85 % photocatalytic degradation efficiency after five cycles, indicating its high reusability potential. Overall, this research offers a facile process for fabricating efficient, stable, and reusable photocatalytic fabrics to tackle the wastewater treatment issue in the textile industry. [ABSTRACT FROM AUTHOR]

Herein, a series of Au@TiO x -Co catalysts were constructed for photocatalytic reduction of CO 2 with H 2 O. Structural characterizations found separate Co and Au nanoparticles (NPs) are produced, and their ratios are variable with different reduction temperatures. Especially Au NPs were coated with oxygen vacancy(V O)-rich TiO x overlayers due to the high-temperature induced topological transition, resulting in interfacial electron transfer to generate Auδ--V O sites. In the photocatalytic reduction of CO 2 , the ratios of Au@TiO x and Co sites strongly influenced the activity and product selectivity. The Au@TiOx-Co(650) catalyst with matched Auδ--V O and Co0 sites is efficient for C-C coupling with a C 2 H 6 production rate of 58.65 μmol·h−1·g cat −1 and selectivity of 25.10%. In situ FTIR demonstrated the Auδ--V O sites are responsible for the H 2 O oxidation process and the conversion of CO 2 to CO via CO 2 ·- species, and syngas is further coupled into C 2 H 6 at the Co0 surface sites via CHO* intermediate. [Display omitted] • Constructed a tandem catalyst integrating noble metal interface sites and non-noble metal surface sites (Auδ--V O and Co0). • Achieved the photocatalytic synthesis of ethane from C-C through the synergistic effect of the tandem sites and obtained a C 2 H 6 production rate of 58.65 μmol·h−1·g cat −1 by regulating the number of sites. • Elucidated the role of Auδ--V O interface sites in the H 2 O oxidation process and the conversion of CO 2 to CO via CO 2 ·- species and Co0 surface sites in the synthesis of C 2 H 6 via CHO* intermediate, and revealed the tandem mechanism. [ABSTRACT FROM AUTHOR]

Here we report the synthesis of branched Tröger's base polymers (x -BTB) with different degree of tetraphenylmethane branch structure by incorporating varied amounts of tetrakis(4-aminopheny)methane into the main chains of Tröger's base polymer (TB). We show that branching increases porosity of x -BTB, leading to improved gas permeability. Specifically, the BET surface area and pore volume of x -BTB polymers increase continuously from 410 to 544 m2 g−1 and 0.584–0.607 cm3 g−1, respectively, for branched polymers containing progressively more branch structure. For CO 2 /N 2 , CO 2 /CH 4 , and O 2 /N 2 binary gas separation, a significant improvement in the gas permeability without obvious compromising the membrane selectivity is observed on the x -BTB membranes with higher branch degree. In particular, for CO 2 /N 2 binary gas separation, the CO 2 permeability of 5 wt%-BTB membrane is 145 Barrers, creating an enhancement of 64.8% as compared to TB membrane. Moreover, x -BTB membranes are much more resistant to physical aging than TB membrane. These results suggest that introduction of tetraphenylmethane branch structure is an effective strategy to fabricate polymeric membranes with high performance suitable for gas separation applications. [Display omitted] • Tetrakis(4-aminopheny)methane (TAPM) exhibited a rigid tetrahedral structure. • Incorporating TAPM into the backbones of TB yielded branched TB polymer (x -BTB). • x -BTB polymers exhibited higher BET surface area than that of TB polymer. • The obtained x -BTB membranes showed a significantly improved gas permeability. [ABSTRACT FROM AUTHOR]

Carbon dioxide reduction, in-situ hydrophobic modification, organic barrier layers, titanium dioxide, transfer limitations Keywords: carbon dioxide reduction; in-situ hydrophobic modification; organic barrier layers; titanium dioxide; transfer limitations EN carbon dioxide reduction in-situ hydrophobic modification organic barrier layers titanium dioxide transfer limitations 1 1 1 08/04/22 20220801 NES 220801 B What you want, where you want it b : Fewer H SB 2 sb O and more CO SB 2 sb molecules can be delivered directly to an in-situ hydrophobic surface for the photocatalytic reduction of CO SB 2 sb to CH SB 3 sb OH. [Extracted from the article]

Small and medium span bridges account for 86% of the bridges in China, and maintenance is necessary to ensure their safety and serviceability. The infrastructure sector causes substantial CO 2 emissions, and it is one of the most polluting sectors. Fly ash (FA) is often used in bridges to reduce CO 2 emissions. Moreover, the lack of temporal information is an important limitation of the life cycle CO 2 assessment of bridges. Taking the upper structure of small and medium span bridges as the research object, this paper proposes a Monte Carlo simulation-based life cycle multi-objective dynamic maintenance strategy optimization model to analyze the life-cycle carbon emissions, costs, and life cycle reliability of different preventive maintenance (PM) and essential maintenance (EM) methods of FA reinforced concrete (RC) beams. Considering the continuous effect of carbon emissions and the net present value of the cost, the time effect of carbon emissions and costs of maintenance and reinforcement at different times is analyzed. Through 50,000 simulations of the case beam, the parameter characteristics of different optimal reinforcement schemes and the relationship between the reliability, life cycle CO 2 emissions, and costs are studied. When introducing the discount rate, the essential maintenance with higher carbon emissions and costs has a marginal effect, i.e., the longer that future carbon emissions and costs occur, the smaller the net present value. The proposed method is demonstrated to be effective at supporting decision making for bridge managers. It would be helpful for identifying the effectiveness of PM and EM, selecting optimal maintenance time interval, and providing a rational estimate of the CO 2 emissions and costs of bridges. • A Multi-objective dynamic maintenance strategy optimization model is proposed. • The time effects of carbon emissions and costs are analyzed. • The parameter characteristics of the optimal maintenance of a T-beam are found. [ABSTRACT FROM AUTHOR]

Hydroxyl chloride has attracted extensive attention in recent years due to its outstanding performance relative to other similar anode materials. In this paper, Co 2 (OH) 3 Cl was introduced into graphene aerogels by a one hot-pot method to fabricate a Co 2 (OH) 3 Cl/graphene aerogels composite (Co 2 (OH) 3 Cl/GA) with a 3D loose-porous structure. The Co 2 (OH) 3 Cl particles are evenly dispersed and independently wrapped within the 3D graphene network, preventing particle agglomeration and alleviating the volume effect while also providing a more convenient multi-dimensional channel for electron transmission. Hence, Co 2 (OH) 3 Cl/GA electrode delivered a superior cycling capacity of 615 mAh g−1 at 1.6 A g−1 after 150 cycles. Furthermore, due to the high conductivity and superior mechanical flexibility of the 3D porous matrix, Co 2 (OH) 3 Cl/GA composite could also achieve good performance even as a free-standing electrode without additives and metal foil. More importantly, the lithium storage mechanism of Co 2 (OH) 3 Cl/GA free-standing electrode during charge-discharging progress could be detected more clearly by ex situ XRD and XANES because the interferences of metal foil and additives were avoided. The mechanism research results reveal that the reversible lithiation/de-lithiation progress of Co 2 (OH) 3 Cl/GA is mainly attributed to the reversible reaction of Co(OH) 2 + 2Li+ + 2e− ⇌ Co0 + 2LiOH. The collected evidence also suggests that the chlorine element may participate in the formation of solid-electrolyte-interface (SEI) film, which is conducive to enhancing the electrode stability. • The Co 2 (OH) 3 Cl anchored in 3D porous matrix as an anode material was fabricated. • The lithium-storage mechanism was investigated by ex-situ XRD and XANES. • The introduction of chlorine element can enhance the cycling stability of Li storage. [ABSTRACT FROM AUTHOR]

The ceramic-molten carbonate (MC) dual-phase membrane is a promising technology for CO 2 capture since the continuously operation and easily coupling with the CO 2 conversion process. In this work, an iron free layered perovskite K 2 NiF 4 structure La 1·5 Sr 0·5 NiO 4±δ (LSN) was used to prepare the LSN-MC dual-phase membrane for CO 2 capture from the simulated flue gas. The crystal structure, chemical compatibility, morphology, permeation performance and stability of the dual-phase membrane were systematically investigated. The results show that LSN is chemical compatible with the molten carbonate phase and chemical stable in the simulated flue gas. The CO 2 permeance of the prepared LSN-MC dual-phase membrane was 5.7 × 10−7 mol s−1 m−2 Pa−1 at 850 °C. With a simulated flue gas as the feed gas, the prepared LSN-MC membrane shows no obvious degradation within 75 h operation. These results demonstrate that the LSN-MC dual-phase membrane is promising for CO 2 capture from the simulated flue gas. [Display omitted] • There are two CO 2 transport routes in the LSN-MC membrane. • CO 2 permeance of 5.7 × 10−7 mol s−1 m−2 Pa−1 was obtained at 850 °C. • The CO 2 permeation performance is stable at 850 °C during 75 h operation. [ABSTRACT FROM AUTHOR]

[Display omitted] • An effective strategy has been established by doping Ce into Cu NPs to tune the electronic state of Cu. • It attains the faradaic efficiency of C 2 H 4 as high as 53% with a current density of 150 mA/cm2. • Such performance is about 2.8-fold increase when compared with Cu NPs. • The electronic structure regulation and defective sites facilitate highly efficient C 2 H 4 production from CO 2 electroreduction. Coupling another metal element tends to produce catalytic controls of high activity and selectivity. However, this action is still poorly explored to improve the selectivity of the electroreduction of CO 2 to C 2 H 4 with high energy density. Herein, Ce-doped Cu nanoparticles (Ce-Cu NPs) are synthesized by one-step co-reduction method and presented a preferable example that promotes selective transformation of CO 2 to C 2 H 4 in a flow-cell configuration. Thereinto, high faradaic efficiency (FE) of C 2 H 4 for Ce-Cu-2 NPs could reach 53% with the current density of 150 mA cm−2, which is 2.8 times higher than that of Cu NPs. The outstanding performance mainly stems from tailoring the doped-Ce content shrinks particle sizes and forms oxygen defects due to the electron effect of nearby Ce atoms, boosting local electronic re-distribution of Cu. Meanwhile, in-situ Raman spectroscopies evidenced that the doping of Ce can enhance Cu site to bond *CO, which were beneficial to C–C coupling and thus endowed the catalyst with the superior catalytic performance in CO 2 electroreduction toward C 2 H 4. [ABSTRACT FROM AUTHOR]

Two kinds of polyimide membranes 6F-AP and 6F-AP/DA (APAF:DABA=3:2) were synthesized and heated between 300–450 °C to study the effect of thermal treatment on the chain structure and gas transport performance of membranes. Fourier Transform Infrared (FI-IR) and X-ray diffraction (XRD) measurements show that heating causes rearrangement of polyimide into rigid polybenzoxazole which prevents the effective stacking of polymer chains leading to the increase of d-spacing and fractional free volume. Positron annihilation results confirm the increase of both size and number of free volume due to the thermal rearrangement. The addition of DABA monomer into 6F-AP causes crosslinking during heating, which results in tightening of the rigid chain spacing of benzoxazole, thus leading to slight decrease in the size and number of free volume. The increase in fraction free volume induced by thermal rearrangement can significantly improve the gas permeability of 6F-AP series membranes, which increases from 16.2 and 3.9 barrer to 271.4 and 200.3 barrer for H 2 and CO 2 , respectively, after increasing the heating temperature from 300 to 450 °C. But this is accompanied by a decrease in gas selectivity due to the increase in free volume size. Finally, by careful tailoring the free volume structure through thermal rearrangement and crosslinking, the 6F-AP/DA polyimide treated at 400 °C exhibits a H 2 permeability of 196.4 barrer and a H 2 /CH 4 ideal selectivity of 90, which is above the 2008 Robeson upper bound. Our results indicate that by designing the functional groups of the reaction monomer plus appropriate thermal treatment, the microstructure of polyimide membrane can be effectively adjusted for high-performance gas separation. [Display omitted] • Cross-Linked Thermally Rearranged Poly(benzoxazole-co-imide) membranes were prepared by heating at varying temperatures. • Thermal rearrangement and thermal crosslinking had been analyzed to understand the change of free volume of polymers. • The free volume of membranes was accurately measured by positron annihilation. • Cross-Linked TR membrane treated at 400 °C exhibited excellent H 2 /CH 4 separation performance exceeding the 2008 upper bound. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) over metal catalysts represents an economically feasible method to convert the greenhouse gas CO 2 into valuable chemical products. Owing to the strong stability of both CH 4 and CO 2 molecules, the reaction usually occurs at very high temperatures, so that the key problem of the reaction is catalysts agglomeration. In this study, we developed a novel core-shell Ru@SiO 2 catalyst by encapsulating Ru nanoparticles in SiO 2 shells through a reversed-phase microemulsion method. The as-produced core-shell Ru@SiO 2 catalyst effectively enhanced the thermal stability of the Ru nanoparticles against gathering at high temperatures, owing to the confinement effect of the SiO 2 shells on the Ru nanoparticles and a sturdy support-metal interaction. Thus, the developed catalyst exhibited a longer lifetime than those of both the unsupported Ru and traditional Ru/SiO 2 catalysts. More importantly, the ultrafine Ru nanoparticles provided both abundant active sites and high instinct activity. Further more, the ultrafine Ru nanoparticles also inhibited carbon generation, thereby preventing catalyst deactivation. To the best of our knowledge, this as-produced core-shell Ru@SiO 2 is one of the best DRM catalysts at high space velocities reported to date. [Display omitted] A novel core-shell Ru@SiO 2 catalyst was developed, which exhibited excellent activity and durability for CO 2 conversion via dry reforming of methane. • Ru@SiO 2 core-shell structured catalyst. • CO 2 conversion to syngas via dry reforming of methane (DRM). • High activity and absolute selectivity. • Inhibition of Ru agglomeration and carbon deposition. • Long lifetime in DRM at 700 oC. [ABSTRACT FROM AUTHOR]