Carbon Neutralization最新文献

Under the global carbon neutrality initiative, carbon emissions from the transportation sector are becoming increasingly prominent due to the growth in vehicle ownership. And electric mobility may be a potentially effective measure to reduce road traffic carbon emissions and achieve a green transformation of transportation. This paper systematically collates the relevant carbon accounting standards for the automotive industry and elaborates the current status of road transport greenhouse gas emissions by combining the data from the International Energy Agency. And by comparing the lifecycle carbon footprint of various energy types of vehicles, the necessity and feasibility of electric mobility to reduce carbon emissions are discussed. However, the comparison of vehicle lifecycle carbon footprints shows that electric vehicles (EVs) are not as environmentally friendly as expected, although they can significantly reduce road traffic carbon emissions. The high carbon emissions from the manufacturing process of the core components of EVs, especially the power battery, reduce the low-carbon potential of electric mobility. Therefore, the carbon emission reduction strategies and outcomes of automakers in the automotive industry chain have been further reviewed. Finally, focusing on vehicle power batteries, this article reviews the technologies such as refined management and echelon utilization that can make EVs more environmentally friendly and promote carbon neutrality in the transportation sector.

CO₂ adducts of hydrophobically modified polyethylenimines (PEIs) are promising alternatives to global warming halogen-containing blowing agents of polyurethanes (PUs), despite the high cost of the raw material PEIs. Herein, an economical synthesis of PEI-like polymers was explored via condensation between pentaethylenehexamine and terephthalaldehyde, followed by chemical reduction of the as-formed Schiff base linkages. The resultant p-phenylene-containing polyamine polymers (PEIPs) could be grafted with alkyl (C_n) side chains and adducted with CO₂ to form a new type of CO₂-releasing blowing agents for PUs designated as yC_n-xPEIP-CO₂s, where x and y represent the backbone molecular weight and the side chain grafting rate, respectively. Among them, the specimen 10%C₈−3.6 kPEIP-CO₂ was the most effective in terms of good dispersibility in PU raw materials, low foam density (about 51 kg/m³), and uniform pore morphology. Moreover, the phenylene linkages enhanced the hydrophobicity of the consequent CO₂ adducts and weakened the intermolecular hydrogen bonding and ionic attraction, both facilitating the dispersion of the corresponding blowing agents into a castor oil-derived polyol, Polycin M-365. The specimen 10%C₈−3.6 kPEIP-CO₂ could disperse as suspended fine floccules that finally aggregated into a flocculent, liquid-like bottom layer, being easily redispersed into the bulk. The unique compatibility with plant oil-derived polyols and the economic availability would make the PEIP-based blowing agents suitable for the next generation of sustainable and biomass-based PU foams.

Back cover image: It is common expectation that decreasing particle size (like thickness) can enhance the activities of catalysts due to geometric and electronic alternations (known as the “catalyst size effect”). However, there are exceptions. In article number CNL266, we have fabricated two metal-organic frameworks (MOFs) sample with different thickness (134.846 and 1.97 nm). In contrast to common expectations, large-thickness MOF has exhibited superior carbon dioxide electroreduction activities as comparison to small-thickness counterpart. Further explanations have been studied systematically by using density function theory (DFT) calculations. The results of this work have challenged the common concept, which would provide new clues for catalyst design toward a number of electrochemical systems.

Front cover image: In article number 10.1002/cnl2.79, Shilin Chen and her co-workers focus on a low-cost method to fabricate an advanced solar evaporator. Lignosulfonate was used as raw material by carbonization to construct lignosulfonate-derived biochar powder. Porous biochar powder as solar absorber was cross-linked with polyvinyl alcohol to prepare a solar interfacial evaporator with efficient desalination performance. The porous structure is advantageous for light capture and multiple scattering, achieving excellent solar energy absorption. Due to the weakened hydrogen bonds between water molecules and polymer network chains, the water molecules are activated to form intermediate water and are evaporated with minimized energy by their configuration. This work provides an economic and efficient strategy for solar-driven desalination and a possible way for high-value utilization of lignin.

Lead-acid batteries (LABs) are widely used as a power source in many applications due to their affordability, safety, and recyclability. However, as the demand for better electrochemical energy storage increases in various fields, there is a growing need for more advanced battery technologies. To meet this need, the application of LABs in hybrid electric vehicles and renewable energy storage has been explored, and the development of lead–carbon batteries (LCBs) has garnered significant attention as a promising solution. LCBs incorporate carbon materials in the negative electrode, successfully addressing the negative irreversible sulfation issue that plagues traditional LABs. Composite material additives and Pb–C composite electrodes have also gained popularity as effective ways to enhance negative electrode performance. This review article focuses on the role of carbon additives in the negative electrode of LCBs and discusses potential future additives that may be incorporated into the development of LCBs. Overall, this article provides insights into the potential of LCBs to offer more efficient and reliable energy storage.

The proton exchange membrane (PEM) water electrolyzer has been considered a versatile approach for practical H₂ production. However, the oxygen evolution reaction (OER) in acid media with complicated proton-coupled electron transfer steps possesses sluggish kinetics and high reaction barriers, severely hindering the development of PEM water electrolyzers. Consequently, high-efficient Ru- and Ir-based catalysts have always been essential to accelerate the OER rate and lower the reaction barrier in PEM water electrolyzer. Therefore, it is very necessary to construct low-cost catalysts with excellent electrocatalytic performances to replace these noble metal-based OER electrocatalysts. In this review paper, a detailed discussion towards fundamentally comprehending the reaction mechanisms of OER was conducted. Accordingly, we proposed the principles of designing advanced OER electrocatalysts with enhanced performances and lowered costs. After that, recent developments in designing various acidic OER electrocatalysts were summarized. Meanwhile, the available regulation strategies about noble metals, nonprecious metals, and metal-free nanomaterials were presented, which are promising for tuning the electronic structures, boosting the electrocatalytic performances, and reducing the costs of electrocatalysts. We also provided the existing challenges and perspectives of various OER electrocatalysts, hoping to promote the development of PEM water electrolyzers.

The solar-driven interfacial evaporation has attracted great attention for the purpose of alleviating freshwater shortage. Lignosulfonate (LS), a main byproduct of sulfite pulping processes, is an abundant natural resource but has not been reasonably utilized. To mitigate the above problems, biochar-based interfacial evaporators derived from LS for solar steam generation were studied in this paper. First, LS was used as a raw material for fabricating carbon materials by carbonization to construct LS-derived carbon (CLS). Meanwhile, LS-derived porous carbon (PCLS) in the presence of CaCO₃ as the activator was also prepared. Next, the two biochar powders, as solar absorbers, were crosslinked with polyvinyl alcohol to prepare the interfacial evaporation materials (PVA@PCLS and PVA@CLS). The open porous structure facilitated the capillary effect and water transport to the evaporator surface. It was also found that the light absorption of the materials could reach more than 97% in the 250–2500 nm range. Moreover, the water evaporation rate and the solar-to-vapor conversion efficiency of PVA@PCLS and PVA@CLS were 2.33, 1.82 kg m⁻² h⁻¹, and 83.7%, 69.3% respectively under 1 sun (1 kW m⁻²) irradiation. The solar-to-vapor conversion efficiency of PVA@PCLS was much increased after the carbonization of LS. In addition, the material cost of PVA@PCLS is only $38.3/kg due to the low price of LS. Therefore, this work provides an economic and efficient strategy for solar-driven desalination and a possible way for the high-value utilization of lignin.

The bottlenecks in photocatalytic materials primarily center on light absorption capacities and rapid charge recombination. Thus, many gigantic effects have been undertaken by worldwide scientists to address the issues. In this concept, carbon-based photocatalysts, such as graphene or graphitic carbon nitrides (g-C₃N₄), would frequently capture scientific fascination due to their distinct properties in catalytic applications. However, traditional materials would possess the drawbacks mentioned above. In the current era, nitrogen-rich graphitic carbon nitrides (g-C₃N₅) have emerged as a promising star for photocatalytic applications due to the significant enhancements in light absorption properties, which can activate in ultraviolet, visible, and even under near-infrared irradiations. This review will summarize the recent progress in the fabrication of g-C₃N₅ and the photocatalytic application of these based materials by thoroughly investigating current literature studies. Thus, updating the current trend in state-of-the-art materials would motivate researchers to explore the field further.

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 −380 mA cm⁻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.

The lithium hexafluorophosphate (LiPF₆) in spent lithium-ion batteries (LIBs) is a potentially valuable resource and a significant environmental pollutant. Unfortunately, most of the LiPF₆ in a spent LIB is difficult to extract because the electrolyte is strongly adsorbed by the cathode, anode, and separator. Storing extracted electrolyte is also challenging because it contains LiPF₆, which promotes the decomposition of the solvent. Here we show that electrolytes in spent LIBs can be collected by a less polar solvent dimethyl carbonate (DMC) wash, and LiPF₆ can be concentrated by simple aqueous extraction by lowering ethylene carbonate (EC) content in the recycled electrolyte. Due to the similar dielectric constant of EC and water, reducing the content of EC in LIB electrolytes, or even eliminating it, facilitates the separation of water and electrolyte, thus enabling the lithium salts in the electrolyte to be separated from the organic solvent. The lithium salt extracting efficiency achieved in this way can be as high as 99.8%, and fluorine and phosphorus of LiPF₆ can be fixed in the form of stable metal fluoride and phosphate by hydrothermal method. The same strategy can be used in industrial waste electrolyte recycling by diluting the waste with DMC and extracting the resulting solution with water. This work thus reveals a new route for waste electrolyte treatment and will also support the development of advanced EC-free electrolytes for high-performance, safe, and easily recyclable LIBs.