Electrochemically grown copper nanoclusters (CuNCs: < 3 nm) from single-atom catalysts have recently attracted intensive attention as electrocatalysts for CO2 and CO reduction reaction (CO2RR/CORR) because they exhibit distinct product selectivity compared with conventional Cu nanoparticles (typically larger than 10 nm). Herein, we conducted a detailed investigation into the size dependence of CuNCs on selectivity for multicarbon (C2+) production in CORR. These nanoclusters were electrochemically grown from single Cu atoms dispersed on covalent triazine frameworks (Cu-CTFs). Operando X-ray absorption fine structure analysis revealed that Cu-CTFs containing 1.21 wt% and 0.41 wt% Cu (Cu(h)-CTFs and Cu(l)-CTFs, respectively) formed CuNCs of 2.0 and 1.1 nm, respectively, at -1.0 V vs. RHE. The selectivity for CORR products was particularly dependent on the size of CuNCs, with the Faraday efficiencies of C2+ products being 52.3% and 32.7% at -1.0 V vs. RHE with Cu(h)-CTFs and Cu(l)-CTFs, respectively. Spherical CuNCs modeling revealed that larger cluster sizes led to a greater proportion of a surface coordination number (SCN) of 8 or 9. Density functional calculations revealed that the CO dimerization reaction was more likely to proceed at SCNs of 8 or 9 compared to SCN of 7 because of the stability of the *OCCO intermediate.

This work aims to recover rare earths from wind turbines NdFeB magnets through pyrometallurgical and hydrometallurgical techniques. First, a NdFeB hydride powder is obtained by decrepitation with hydrogen. Subsequently, this powder was subjected to a chlorination roasting process and successive leaching with water to bring the metals into solution. This was followed by a liquid-liquid extraction to remove the iron and purify the rare earth solution. For this purpose, Aliquat 336 diluted in Solvesso was selected as the iron selective extraction agent. As a single extraction was not enough for complete iron removal, a second Fe extraction step was carried out. This second extraction step was performed using the restored organic phase. This restoration was achieved by treating the organic phase with Na2SO3 and then washing it with a 3M HCl solution. In this way, the process was achieved more sustainably. Finally, the rare earths contained in the final solution were precipitated using oxalic acid to obtain mixed rare earth oxalates.

Sluggish oxygen evolution reaction (OER) is a crucial part of water splitting and solar fuel generation, which limits their utilization. Ni3S2 is a promising OER catalyst, in which surface reconstruction is an important step to improve performance. In this study, DFT calculations were employed to investigate the effect of surface reconstruction on (001), (110), and (101) surfaces of Ni3S2 in alkaline OER. According to the Pourbaix diagram and surface free energy landscape, Ni3S2 is prone to transform into Ni oxides and (oxy) hydroxides under alkaline OER conditions. This process induces exposed S atoms to leach and O from the electrolyte to incorporate S sites, thereby lowering the Bader charge of *O and increasing [[EQUATION]], and then decrease [[EQUATION]], the free energy penalty of the potential determining step. In general, the surface reconstruction enhances the OER activity through S leaching and adjusting the coordination environment. We believe this work not only provides insights into the clarification of surface reconstruction, but also provides a valuable guideline for the further discovery of efficient TM-based sulfides.

Capacitive deionization (CDI) is a novel, cost-effective and environmentally friendly desalination technology that has garnered significant attention in recent years. Carbon materials, owing to their excellent properties, have become the preferred electrode materials for CDI. Given the significant differences between different ions, ion-selective performance has emerged as a critical aspect of CDI applications. However, comprehensive reviews on the selective ion separation capabilities of carbon materials for CDI remain scarce. This review examines the progress in developing carbon materials for ion-selective separation in CDI, focusing on regulatory mechanisms and representative materials. It also discusses the applications of selective CDI carbon materials in areas such as heavy metal removal, nutrient recovery, seawater desalination resourcing, and water softening. Furthermore, the challenges and future prospects for advancing carbon materials in CDI are explored. This review aims to provide theoretical insights and practical guidance for utilising carbon materials in wastewater treatment and resource recovery.

Life cycle assessment (LCA) was used, next to green chemistry concepts, to compare the full environmental impacts of the epoxidation of a bio-based monomer, which can be used for the synthesis of vitrimers. On a laboratory scale, the synthesis of the monomer can either be done via a petrochemical route or via an enzymatic reaction pathway. Both reaction pathways were initially optimized to minimize the impact of suboptimal routes on the sustainability evaluation. The subsequent assessment of the enzymatic routes shows lower impact factors for most criteria compared to the petrochemical routes. A significant drawback of the enzymatic reaction, however, is its electricity consumption. The yields of the respective reactions also proved to be crucial; realistic changes in yields revealed the petrochemical reaction to be more sustainable in some cases. LCA is therefore a valuable tool for the preliminary evaluation of the developed synthesis pathways and to identify the critical adjustments needed to increase the sustainability of each reaction.

Photocatalytic conversion of CO2 into value-added chemicals offers a propitious alternative to traditional thermal methods, contributing to environmental remediation and energy sustainability. In this respect, covalent organic frameworks (COFs), are crystalline porous materials showcasing remarkable efficacy in CO2 fixation facilitated by visible light owing to their excellent photochemical properties. Herein, we employed Lewis acidic Zn(II) anchored pyrene-based COF (Zn(II)@Pybp-COF) to facilitate the photocatalytic CO2 utilization and transformation to 2-oxazolidinones. Notably, Zn-COF displayed absorption of visible light, with an optimal band gap of 1.8 eV, effectively catalyzing light-mediated functionalization of propargylic amines to 2-oxazolidinones under green conditions. Detailed experimental and theoretical mechanistic investigations demonstrated that light plays a crucial role in enhancing the efficacy of the photocatalyst, as it activates inert CO2 molecule to radical anion and thereby, lowers the energy barrier for its subsequent cyclization reaction with propargylic amine. Additionally, Zn-COF demonstrates promising catalytic performance utilizing dilute gas as the CO2 source. This is the first report regarding noble metal-free, Zn-COF exhibiting excellent photocatalytic carboxylative cyclization of CO2 with propargyl amines to prepare 2-oxazolidinones using dilute gas (13% CO2). This study offers a new direction for rationally constructing noble metal-free eco-friendly photocatalysts for achieving CO2 fixation reactions under eco-friendly conditions.

In the pursuit of high-energy-density lithium metal batteries (LMBs), the development of stable solid electrolyte interphase (SEI) is critical to address issues such as lithium dendrite growth and low Coulombic efficiency. Herein, we propose a facile strategy for the in-situ fabrication of a LiCl-rich artificial SEI layer on Li surfaces through reaction of MoCl5 with Li (Li@MoCl5). The resulting artificial SEI significantly enhances the uniformity of Li deposition, effectively suppresses dendrite formation, and improves electrochemical performance. As a result, Li@MoCl5 symmetric cells demonstrate remarkable stability, achieving continuous cycling of 4200 h under a high current density of 10 mA cm-2 with an areal capacity of 1 mAh cm-2. Full-cells employing Li@MoCl5 exhibit superior cycling stability and rate capability, even at high cathode loading (17 mg cm-2). These results highlight the potential of this interface engineering strategy for advanced practical application of LMBs.

Layered double hydroxides (LDHs), which resemble hydrotalcite, are a type of materials with cationic layers and exchangeable interlayer anions. They have drawn lots of curiosity as a high-temperature CO2 adsorbent because of its quick desorption/sorption kinetics and renewability. Due to its extensive divalent or trivalent cationic metals, high anion exchange property, memory effect, adjustable behavior, bio-friendliness, easy to prepare and relatively low cost, the LDHs-based materials are becoming increasingly popular for photocatalytic CO2 reduction reaction (CO2RR). Fabrication and modification are good ways to move forward the advancement of LDHs-based catalysts, which will help chemistry and materials science make great progress. In this review we discussed structural characteristics and the methods for preparation and modification of LDHs-based photocatalysts. We also highlighted and discussed the major developments and applications in photocatalytic CO2RR as well as the photocatalytic mechanism. The goal of the present review is to give a broad summary of the various LDHs-based photocatalysts and the corresponding design strategies, which could motivate more excellent research works to explore this kind of CO2RR photocatalysts to further increase CO2 conversion yield and selectivity.

Direct photochemical conversion of CO2 into a single carbon-based product currently represents one of the major issues in the catalysis of the CO2 reduction reaction (CO2RR). In this work, we demonstrate that the combination of an organic photosensitizer with a heptacoordinated iron(II) complex allows to attain a noble-metal-free photochemical system capable of efficient and selective conversion of CO2 into CO upon light irradiation in the presence of N,N-diisopropylethylamine (DIPEA) and 2,2,2-trifluoroethanol (TFE) as the electron and proton donor, respectively, with unprecedented performances (ΦCO up to 36%, TONCO > 1000, selectivity > 99%). As shown by transient absorption spectroscopy studies, this can be achieved thanks to the fast rates associated with the electron transfer from the photogenerated reduced dye to the catalyst, which protect the dye from parallel degradation pathways ensuring its stability along the photochemical reaction. These results point out how the profitable merging of molecular species based on cheap and abundant elements can have great potential to target efficient and selective transformations crucial for the conversion of solar energy into fuels.

Beyond directed evolution, ancestral sequence reconstruction (ASR) has emerged as a powerful strategy for engineering proteins with superior functional properties. Herein, we harnessed ASR to uncover robust PET hydrolase variants, expanding the repertoire of PET-degrading enzymes and providing deeper insights into the underlying mechanisms of PET hydrolysis. As a result, ASR1-PETase, featuring a unique cysteine catalytic site, was discovered. Despite having only 19.3% sequence identity with IsPETase, ASR1-PETase demonstrated improved PET degradation efficiency, with a finely-tuned substrate-binding cleft. Comprehensive experimental validation, including mutagenesis studies and comparisons with six state-of-the-art PET hydrolases, combined with microsecond-scale molecular dynamics (MD) simulations and QM-cluster calculations, revealed that ASR1-PETase's C161 catalytic residue assisted with the wobbled H242 can simultaneously cleave both ester bonds of BHET-a feature not commonly observed in other PET hydrolases. This mechanism may serve as the primary driving force for accelerating PET hydrolysis while minimizing the accumulation of the intermediate MHET, thereby enhancing the efficiency of TPA production.

This contribution uses a rapid microwave-assisted hydrothermal synthesis method to produce a vanadium-based K1.92Mn0.54V2O5·H2O cathode material (quoted as KMnVOH). The electrochemical performance of KMnVOH is tested in an aqueous electrolyte, which exhibits a remarkable specific capacity of 260 mA·h g-1 at 5 C and retains 94% of its capacity over 2000 cycles. In contrast to the aqueous electrolyte, the KMnVOH electrode tested in the organic electrolyte provides a modest discharge capacity of 60 mAh⋅g-1 at C/10, and the electrogravimetric analysis indicates that the charge storage mechanism is solely due to non-solvated Zn2+ intercalation. In aqueous electrolyte tests, Zn species insertion, interfacial pH increase, and subsequent formation of Znx(OH)y(CF3SO3)2x-y·nH2O (ZHT) are supported by in-situ EQCM. Ex-situ XRD measurements also confirm the ZHT formation and its characteristic plate-like structure is observed by SEM. The ion diffusion coefficient values in aqueous and non-aqueous electrolytes are very similar according to the GITT analysis, while it is expected to be higher in aqueous electrolytes. These results may further emphasize the complex redox dynamics in the aqueous electrolyte, namely the difficulty of intercalation of bare Zn2+, strong Zn2+ solvation in the bulk electrolyte, solvent or proton intercalation, and ZHT formation.

Although microporous carbons can perform well for CO2 separations under high pressure conditions, their energy-demanding regeneration may render them a less attractive material option. Here, we developed a large-pore mesoporous carbon with pore sizes centered around 20-30 nm using a templated technical lignin. During the soft-templating process, unique cylindrical supramolecular assemblies form from the copolymer template. This peculiar nanostructuring takes place due to the presence of polyethylene glycol (PEG) segments on both the Pluronic® template and the PEG-grafted lignin derivative (glycol lignin). A large increase in CO2 uptake occurs on the resulting large-pore mesoporous carbon at 270 K close to the saturation pressure (3.2 MPa), owing to capillary condensation. This phenomenon enables a CO2/CH4 selectivity  (SCO2/CH4, mol/mol) of 3.7 at 270 K and 3.1 MPa absolute pressure, and a swift pressure swing regeneration process with desorbed CO2 per unit pressure far outperforming a benchmark activated carbon (i.e., notably rapid decrease in the amount of adsorbed CO2 with decreasing pressure). We propose large-pore mesoporous carbons as a novel family of CO2 capture adsorbents, based on the phase-transition behavior shift of CO2 in the nanoconfined environment. This novel material concept may open new horizons for physisorptive CO2 separations with energy-efficient regeneration options.

Efficient recovery of metals from secondary resources is essential to address resource shortages and environmental crises. The development of a cheap, environmentally friendly, and highly efficient recovery pathway is essential for resource retrieval. In this study, we propose a high-efficiency extraction approach utilizing bis(2,4,4-trimethylpentyl) phosphonic acid (Cyanex272) to recover cobalt from waste choline chloride/ethylene glycol (Ethaline) electrolyte containing Co(II) ions. By adjusting the water content of the system to modify the ligand of Co(II) ions, combined with pH adjustment, we achieved an extraction efficiency exceeding 99.9% for Co(II) ions. Subsequently, oxalic acid (OA) was added as a stripping agent to achieve a recovery efficiency of over 99.4% for cobalt. The extractant can be recycled more than 15 times after stripping. Impressively, more than 98.3% of the water-diluted Ethaline extraction raffinate was recovered through reduced pressure distillation while maintaining the structure of recovered Ethaline unchanged. This work provides an economical, efficient, and sustainable pathway for treating waste Ethaline electrolyte-containing metal ions.

Hole transport layer (HTL)-free carbon-based perovskite solar cells (C-PSCs) own outstanding potential for commercial applications due to their attractive advantages of low cost and superior stability. However, the abundant defects and mismatched energy levels at the interface of the perovskite/carbon electrode severely limit the device efficiency and stability. Constructing a 2D layer on the surface of 3D perovskite films to form 2D/3D heterojunctions has been demonstrated to be an effective method of passivating surface defects and optimizing the energy level alignment in almost all kinds of PSCs. Due to the unique structure of HTL-free C-PSCs, 2D/3D heterojunctions play especially important roles. This review article summarizes the reports of 2D/3D perovskite heterojunctions in HTL-free C-PSCs. It describes the contributions of 2D/3D heterojunctions in terms of their roles in defect passivation, energy level optimization, and stability improvement. Finally, challenges and prospects of 2D/3D heterojunction for further development of HTL-free C-PSCs are highlighted.

The advancement of photocatalytic technology for solar-driven hydrogen (H2) production remains hindered by several challenges in developing efficient photocatalysts. A key issue is the rapid recombination of charge carriers, which significantly limits the light-harvesting ability of materials like BiOCl and Cu2SnS3 quantum dots (CTS QDs), despite the faster charge mobility and quantum confinement effect, respectively. Herein, a BiOCl/CTS (BCTS) heterostructure was synthesized by loading CTS QDs onto BiOCl 2D nanosheets (NSs), that demonstrated excellent photocatalytic activity under visible light irradiation. The improved hydrogen generation rate (HGR) was primarily due to an interfacial Bi-S bond formation, which facilitates the creation of direct Z-scheme heterojunction and an internal electric field at the interface, promoting efficient charge transfer between BiOCl and CTS. Moreover, due to the amalgamation of Bi-S bond formation and interfacial electric field, the optimized BCTS-5% heterostructure exhibited a high HGR of 8.27 mmol·g⁻¹·h⁻¹, and an apparent quantum yield (AQY) of 61%, ~ 4 times higher than pristine BiOCl. First-principles density functional theory (DFT) calculations further revealed the presence of a Bi-S bond with a bond length of ~2.85 Å and a minimal work function of 2.37 eV for the heterostructure, both of which are critical for enhancing H2 generation efficiency.

Concentrated solar-driven CO2 reduction is a breakthrough approach to combat climate crisis. Harnessing the in-situ coupling of high photon flux density and high thermal energy flow initiates multiple energy conversion pathways, such as photothermal, photoelectric, and thermoelectric processes, thereby enhancing the efficient activation of CO2. This review systematically presents the fundamental principles of concentrated solar systems, the design and classification of solar-concentrating devices, and industrial application case studies. Meanwhile, key technological advances-from theoretical foundations to practical applications-are also discussed. At the microscopic level, a comprehensive analysis of multiscale reaction kinetics within the domain of photothermal synergistic catalysis has been conducted. This analysis elucidates the significance of catalyst design, further detailing the intricate regulatory mechanisms governing reaction pathways and active sites through nanostructured catalysts, single-atom catalysts, and metal-support interactions. However, the transition from laboratory research to industrial-scale application still faces challenges, including the complexity of system integration, energy density optimization, and economic feasibility. This review provides a theoretical framework and practical guidance through a complete investigation of current technological bottlenecks and future development directions, with the aim of driving key advances in concentrated solar-driven CO2 reduction catalysis.

Valorization of carbohydrate-rich biomass by conversion into industrially relevant products is at the forefront of research in sustainable chemistry. In this work, we studied the inulin conversion into 5-hydroxymethylfurfural, in deep eutectic solvents, in the presence of acidic task-specific ionic liquids as catalysts. We employed aliphatic and aromatic ionic liquids as catalysts, and choline chloride-based deep eutectic solvents bearing glycols or carboxylic acids, as solvents. The reactions were performed in a biphasic system, with acetone as a benign extracting solvent, enabling continuous extraction of 5-HMF. We aimed to find the best experimental conditions for this transformation, in terms of catalyst loading, solvent, reaction time and temperature to achieve an economical and energy efficient process. We also analyzed the results in terms of solvent viscosity and structural organization as well as catalysts acidity, to elucidate which structural features mostly favour the reaction. Under optimized conditions, we obtained a yield in 5-HMF of 71 %, at 80 °C in 3 h. Our system can be scaled up and recycled three times with no loss in yield. Finally, comparison with the literature shows that our system achieves a higher yield under milder conditions than most protocols so far reported for the same transformation.

Elevating the long-wavelength activation of photocatalysts represents a formidable approach to optimizing sunlight utilization. Polythiophene (PTh), although renowned for its robust light absorption and excellent conductivity, is largely overlooked for its potential as a photocatalyst due to the swift recombination of photogenerated charge carriers. Herein, we unveil that the strategic introduction of an aromatic ring containing varying nitrogen content into PTh instigates polarized charge distribution and facilitates the narrowing of the band gap, thereby achieving efficient photocatalytic activities for both hydrogen and hydrogen peroxide generation. Notably, the best sample, PTh-N2, even demonstrates photocatalytic activity in the red light region (600-700 nm). This study offers a promising avenue for the development of polymer photocatalysts with efficient photocatalytic performance for red light-induced photocatalysis.

The tightly connected structure of polybenzimidazole (PBI) membrane can be relaxed by solvent/nonsolvent solution to achieve a high proton conductivity for vanadium redox flow battery (VRFB). However, the nature behind the solvent/nonsolvent strategy is not unraveled. This work proposes a guideline to analyze the effect of PBI membrane relaxing formulas based on the interactions between different components in membranes. The supreme-efficient PBI membrane derived by the DMSO/formamide formula according to the guideline displays a marvelous performance for VRFB, with the proton conductivity boosted by 4300% (from 1.93 to 83.33 mS cm-1), and VRFB assembled with this membrane achieves an outstanding energy efficiency of 82.5% under 200 mA cm-2. Moreover, this work profoundly unravels the structure, property and performance relationship of PBI membrane, which is of great value for the development of membranes.

Inverted perovskite solar cells (IPSCs) utilizing nickel oxide (NiO) as hole transport material have made great progress, driven by improvements in materials and interface engineering. However, challenges remain due to the low intrinsic conductivity of NiO and inefficient hole transport. In this study, we introduced MoS nanoparticles at the indium tin oxide (ITO) /NiO interface to enhance the ITO surface and optimize the deposition of NiO, resulting in increased conductivity linked to a ratio of Ni:Ni. This interface modification not only optimized energy level but also promoted hole transport and reduced defects. Consequently, IPSCs with MoS modified at ITO/NiO interface achieved a champion power conversion efficiency (PCE) of 21.42 %, compared to 20.25 % without modification. Additionally, unencapsulated IPSCs with this interface modification displayed improved stability under thermal, light, humidity and ambient conditions. This innovative strategy for ITO/NiO interface modification efficiently promotes hole transportation and can be integrated with other interface engineering approaches, offering valuable insights for the development of highly efficient and stable IPSCs.

Polyesters featuring a linear topology and in-chain 1,3-cyclobutane rings, synthesized via ring-opening polymerization (ROP) of 2-oxabicyclo[2.1.1]hexan-3-one (4R-BL, R = Bu, Ph) through a coordination-insertion mechanism, display excellent thermal and hydrolytic stability, making them promising candidates for sustainable circular materials. However, achieving diverse topological and stereochemical structures remains challenging. Herein, we demonstrate precise control over linear and cyclic topologies of these polyesters and the conformation of in-chain cyclobutane rings through anionic  ROP of 4R-BL with appropriate catalysts or initiators. Using tert-butoxide (tBuOK) as the catalyst, low loading (0.05-0.1 mol%) produces high-molar-mass cyclic polyester P(4R-BL) (up to 571 kg/mol), whereas high loading (2 mol%) promotes transesterification and isomerization, ultimately yielding cyclic oligomers. Remarkably, the tetramer (4Ph-BL)4undergoes conformational turnover of the puckered cyclobutane rings and can be repolymerized into polymer P(4Ph-BL). This establishes a "monomer ⇄ polymer ⇄ tetramer" dual closed-loop life cycle, enhancing the potential for a circular material economy.