Carbon Neutralization最新文献

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.

Inside front cover image: The ambitious goal of cabron neutralization requires the further development of fast energy storage devices like supercapacitors, while the severe self-discharge of conventional electrochemical double-layer capacitors has greatly limited their development. The recent emergence of conjugately configured supercapacitor has brought a new frontier for alleviating self-discharge. In article number CNL255, The researchers explored how the carbon coating strategy, which has already been widely used to modify active materials to enhance conductivity and cycling stability, could introduce profound and complex influence to self-discharge property for active materials specifically used for conjugatedly configured supercapacitors. The proposed conjugated configuration as well as the optimization strategy specifically for such device is expected to provide a general and powerful approach for alleviating self-discharge.

Back cover image: Hollow structure materials usually exhibit good performance in the field of electrochemistry because of their large specific surface area and abundant active sites. Prussian blue and its analogs (PB/PBAs) usually contain two or more kinds of transition metal elements, and the synergistic effect between different metal elements often improves the performance. Hollow structure PB/PBAs can be synthesized by adjusting the synthesis strategy. Moreover, a variety of hollow structure derived materials can be obtained via easy derivative treatment for PB/PBAs. These derivatives can alleviate the poor conductivity of PB/PBAs, thus exhibiting better electrochemical performance. In article number CNL264, the synthesis strategies of hollow PB/PBAs and their derived materials are systematically summarized, the applications of related materials in the field of electrochemistry are introduced in detail, and the prospects and challenges are further analyzed.

Front cover image: Sulfurized polyacrylonitrile (SPAN) with a “solid-solid” conversion mechanism in carbonated-based electrolyte eradicating the polysulfides shutting issue is considered as an ideal cathode for stabilizing lithium sulfur (Li-S) batteries. However, the sluggish reaction kinetics and low sulfur content of the SPAN limits its practical application. In article number CNL261, the MoS₂ doped SPAN (MoS₂@SPAN) is demonstrated to accelerate the solid-solid conversion kinetics of SPAN for high-power and long-life Li-S batteries. Benefitting from the accelerated lithium-ion transfer rate, a fast ion transport channel and enhanced redox reaction kinetics of sulfur to Li₂S₂/Li₂S is realized via MoS₂ catalysis, and excellent electrochemical performance is achieved. This work provides a reliable strategy for the design of SPAN cathode in high-rate and long-term Li-S batteries.