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Piezoelectric energy harvesting devices (PEHDs) for road installation are being researched as potentially low-emission electrical generators, but their life cycle greenhouse gas (GHG) emissions must be assessed to guide their design and implementation toward minimizing their carbon footprint. Parametric life cycle assessments (LCAs) of a PEHD, its generator, and the piezoelectric material were performed using data from a pilot-scale PEHD installation. The GHG emissions of the lead zirconate titanate (PZT) piezoelectric stack were determined to be lower than previously reported in the literature at 10.81-15.90 kg CO2eq/kg piezoelectric. The GHG emissions of electricity generated by a PEHD range from 48.65-588.63 g CO2eq/kWh, spanning from similar to renewables to slightly higher than electricity from natural gas. Sensitivity analysis indicated that spatial parameters and the device lifetime had the largest influence on the LCA results. PEHDs installed on roads show potential to be low-GHG emission energy systems.

Metal–organic frameworks (MOFs) have emerged as promising materials for triboelectric nanogenerators (TENGs), but the effects of ligand choice on triboelectric charge remain underexplored. Hence, this paper demonstrates the effect of single, binary, and ternary ligands on TENG performance of cobalt/cerium‐based (Co─Ce) bimetallic MOFs utilizing 2‐methylimidazole (2Melm), terephthalic acid (BDC), and benzene tricarboxylic acid (BTC) as ligands. The detailed structural characterization revealed that varying ligand chemistries led to distinct MOF features affecting TENG performance. Single ligand bimetallic MOFs (designated as CoCe‐2MeIm, CoCe‐BDC, CoCe‐BTC) has lower performance than binary ligand (designated as CoCe‐2MeIm‐BDC, CoCe‐2MeIm‐BTC, CoCe‐BDC‐BTC) and ternary ligand MOFs (designated as CoCe‐2MeIm‐BDC‐BTC). Among all, the binary ligand MOF, CoCe‐2MeIm‐BTC, shows the best results (598 V, 26.7 µA) due to the combined effect of imidazole ring and (─COO─) groups. This is attributed to lone pairs on nitrogen atoms and a delocalized π‐electron system in imidazole system in this material. CoCe‐BTC has the lowest results (31 V, 3.2 µA) due to the bulkier nature of the electron‐withdrawing (─COO─) groups and their impact on the π‐electron system of the benzene ring. This study showcases the potential of ligand chemistry manipulation to control triboelectric charge and thereby enhance MOF‐based TENG performance. [ABSTRACT FROM AUTHOR]

The electrochemical series is a useful tool in electrochemistry, but its effectiveness in materials chemistry is limited by the fact that the standard electrochemical series is based on a relatively small set of reactions, many of which are measured in aqueous solutions. To address this problem, we have used machine learning to create an electrochemical series for inorganic materials from tens of thousands of entries in the Inorganic Crystal Structure Database. We demonstrate that this series is generally more consistent with oxidation states in solid-state materials than the series based on aqueous ions. The electrochemical series was constructed by developing and parameterizing a physical, human-interpretable model of oxidation states in materials. We show that this model enables the prediction of oxidation states from composition in a way that is more accurate than a state-of-the-art transformer-based neural network model. We present applications of our approach to structure prediction, materials discovery, and materials electrochemistry, and we discuss possible additional applications and areas for improvement. To facilitate the use of our approach, we introduce a freely available website and API. [ABSTRACT FROM AUTHOR]

The perspectives of technological advances needed for short term energetic transition are briefly reviewed and discussed critically. In particular, the technologies for the greenhouse gas emission-free production of electrical energy, its storage and transport, the production, transport, storage and use of hydrogen, and the use of biomass derived technologies are shortly and critically reviewed. Critical aspects are emphasized. The role of chemistry, and in particular materials chemistry and engineering, in short-term developments are underlined. [ABSTRACT FROM AUTHOR]

Summary: The evolution from subtractive to modified semi-additive (mSAP) and semi-additive (SAP) processes has heightened the importance of electroless plated (ELP) copper (Cu) peel strength in the printed circuit board industry. This study introduces a wet process for depositing Cu on liquid crystal polymer (LCP) using advanced electroless plating, incorporating a polyethylenimine (PEI) surfactant, a homemade nano-sized palladium (Pd) activator, and a micro-sculpturing treatment. By adjusting PEI immersion time and substrate roughness in the sub-micrometer domain, the peel strength of the ELP Cu film ranges from under 10 gf/cm to over 600 gf/cm. This wide range meets both low peel strength needs of mSAP peelable Cu foil and the high strength required in SAP. Characterization techniques, including atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), water contact angle (WCA) measurements, and fracture analysis, reveal that ELP Cu peel strength is driven by a synergistic effect between molecular interaction and physical anchoring.

Abstract Metal–organic frameworks (MOFs) have emerged as promising materials for triboelectric nanogenerators (TENGs), but the effects of ligand choice on triboelectric charge remain underexplored. Hence, this paper demonstrates the effect of single, binary, and ternary ligands on TENG performance of cobalt/cerium‐based (Co─Ce) bimetallic MOFs utilizing 2‐methylimidazole (2Melm), terephthalic acid (BDC), and benzene tricarboxylic acid (BTC) as ligands. The detailed structural characterization revealed that varying ligand chemistries led to distinct MOF features affecting TENG performance. Single ligand bimetallic MOFs (designated as CoCe‐2MeIm, CoCe‐BDC, CoCe‐BTC) has lower performance than binary ligand (designated as CoCe‐2MeIm‐BDC, CoCe‐2MeIm‐BTC, CoCe‐BDC‐BTC) and ternary ligand MOFs (designated as CoCe‐2MeIm‐BDC‐BTC). Among all, the binary ligand MOF, CoCe‐2MeIm‐BTC, shows the best results (598 V, 26.7 µA) due to the combined effect of imidazole ring and (─COO─) groups. This is attributed to lone pairs on nitrogen atoms and a delocalized π‐electron system in imidazole system in this material. CoCe‐BTC has the lowest results (31 V, 3.2 µA) due to the bulkier nature of the electron‐withdrawing (─COO─) groups and their impact on the π‐electron system of the benzene ring. This study showcases the potential of ligand chemistry manipulation to control triboelectric charge and thereby enhance MOF‐based TENG performance.

Summary: This study investigates the effect of twinning on the corrosion behavior of AZ31B magnesium alloy using solid solution heat treatment (SHT) and laser shock peening (LSP) techniques. The corrosion characteristics are assessed by scanning electron microscopy (SEM), scanning Kelvin probe force microscopy (SKPFM), zero resistance ammeter (ZRA), scanning vibrating electrode technique (SVET), and electrochemical tests. Results indicate that the twinning region in AZ31B magnesium alloy, enriched with {101¯2} tensile twins induced by laser shock, demonstrates increased corrosion susceptibility. This region exhibits higher electrochemical activity and an accelerated corrosion rate compared to the matrix region. Micro-galvanic coupling between the twinned and matrix regions promotes faster dissolution of the alloy. Additionally, the corrosion product film on the surface is extensively cracked and propagates to the matrix corrosion surface, confirming that {101¯2} tensile twins provide inadequate protection against corrosion in AZ31B alloy.

Advancements in energy storage technologies such as Li-based batteries depend on a deep understanding of the chemical and structural aspects of critical interfaces. Among these, the solid electrolyte interphase (SEI) governs how batteries operate yet remains one of the most elusive to characterize due to its rapid degradation under an electron beam and sensitivity to ambient conditions. In recent years, cryogenic electron microscopy (cryo-EM) has emerged as a promising technique to provide atomic-resolution imaging of beam-sensitive battery materials. Distinct SEIs have been discovered with unique chemical compositions and structural features. In this perspective, the role of cryo-EM in uncovering the physicochemical properties of three classes of SEIs (i.e., compact, extended, and indirect SEI) will be defined and discussed. Furthermore, an in-depth analysis of new cryo-EM imaging modalities will be provided to highlight directions for the future development of cryo-EM.

Summary: Nitrogen doped carbon materials have been studied as catalyst support for ammonia decomposition. There are 4 different types of nitrogen environments (graphitic, pyrrolic, pyridinic and nitrogen oxide) on the amorphous support identified. In this paper, we report a 5%Ru on MgCO3 pre-treated nitrogen doped carbon catalyst with high content of edge nitrogen-containing sites which displays an ammonia conversion rate of over 90% at 500°C and WHSV = 30,000 mL gcat−1 h−1. It also gives an impressive hydrogen production rate of 31.3 mmol/(min gcat) with low apparent activation energy of 43 kJ mol−1. Fundamental studies indicate that the distinct average Ru-N4 coordination site on edge regions is responsible for such high catalytic activity. Ammonia is stepwise decomposed via a Ru-N(H)-N(H)-Ru intermediate. This associative mechanism circumvents the direct cleavage of energetic surface nitrogen from metal to form N2 hence lowering the activation barrier for the decomposition over this catalyst.

Summary: Hydrogen is a promising combustion improver for use with ammonia fuels, but a cost-effective method for easily producing hydrogen from ammonia at a high rate has yet to be developed. Here, we show that microwave irradiation instantly triggers oxidative decomposition of ammonia over a Co/Ce0.5Zr0.5O2 catalyst to produce hydrogen at a high rate. The microwave irradiation rapidly heats the inside of the catalyst from room temperature to the catalytic auto-ignition temperature of ammonia, thus initiating exothermic oxidative decomposition of ammonia to produce hydrogen. This method provides a highly efficient means of producing hydrogen for potential use in a carbon-free, ammonia-fueled power generation process.

Summary: In this study, the theoretical calculations proves that the combination of oxygen vacancy and amorphous carbon films in TiO2 (VO-CT) can effectively reduce the energy bandgap and work function. The minimum Gibbs free energies required for the CO2RR reaction of VO-CT are 0.20 eV, which is lower than pure TiO2. The amorphous c@TiO2 nanomaterials with oxygen vacancy and mesoporous structures (VO-MCT) are prepared with the P123 surfactant as the template and oxalic acid as an inducer. The electron paramagnetic resonance indicates the presence of abundant oxygen vacancy defects in the samples. UV-vis spectra indicate that the mesoporous structure enhances light absorption capacity. The photocatalytic CO2 reduction tests show that the highest conversion rates for CH4 and CO of VO-MCT are 14 μmol g−1 h−1 and 10.66 μmol g−1 h−1, respectively. The electron consumption rate of VO-MCT is 12.43 times higher than that of commercial TiO2 (P200).

Summary: Direct and stable conversion of CO2 to aromatics (CTA) is an attractive route for reducing CO2 emissions. However, due to the chemical inertness of CO2, direct CTA reaction with high aromatics selectivity is still challenging. In this work, a tandem catalyst Zn0.1Ti0.9Ox/HZSM-5 with appropriate density and strength of acid sites exhibits a high aromatics selectivity of 67.2% and long-term stability over 100 h. Furthermore, the total selectivity of benzene, toluene, and xylene achieves 24.1% over Zn0.1Ti0.9Ox/HZSM-5 with a modified hydrophilic surface. In addition, the CTA via the formate route has been determined in this reaction system.

Summary: Electrospinning of nanocarbons such as graphene and carbon nanotubes typically produces mats composed of one-dimensional fibers where the carrier polymer encapsulates the nanocarbons. Recently it was found that decreasing the amount of carrier polymer in approaching the electrospinning-electrospray boundary for graphene suspensions resulted in retention of the graphene two-dimensional anisotropy with one-dimensional carrier polymer fibers connecting flakes. We explored a similar decrease in carrier polymer in MWCNT suspensions to investigate the network topology that might ensue. Unexpectedly, two-dimensional leaflet meso-networks were obtained wherein the leaflets comprise laterally aligned MWCNTs one to several nanotubes thick. A mechanism based on capillary force-driven MWCNT self-assembly activated by menisci formed during drying of electrospun fibers is presented. Such materials offer new approaches to producing high surface-area coatings for catalytic and energy applications and suggest ways of formulating two-dimensional MWCNT assemblies in metal foams and other open-cell porous materials.

Summary: Foodborne illness caused by consuming foods contaminated by pathogens remains threating to the public health. Despite considerable efforts of using renewable source materials, it is highly demanding to fabricate food packaging with multiple properties including eco-friendliness, bactericidal effect and biocompatibility. Here, sodium lignosulfonate (SL) and ZnO nanoparticles (ZnO NPs) were used as functional filler and structure components, respectively, on the cellulose nanofibers (CNFs)-based films, which endows the produced membrane (CNF/SL-ZnO) the UV-light blocking, antioxidant, and antimicrobial characteristics. Due to the interconnected polymeric structure, the prepared CNF/SL-ZnO films possessed considerable mechanical properties, thermal stability, and good moisture barrier capability. Moreover, the tested samples exhibited an improved shelf life in food packaging. Furthermore, metagenome analysis revealed superior biodegradability of obtained films with negligible side effect on the soil microenvironment. Therefore, the biocompatible, degradable, and antibacterial CNF/SL-ZnO film holds enormous potential for sustainable uses including food packaging.

Summary: The electrochemical carbon dioxide reduction (CO2RR) on Cu-based catalysts is a promising strategy to store renewable electricity and produce valuable C2+ chemicals. We investigate the CO2RR on Cu-Ag nanostructures that have been electrodeposited in a green choline chloride and urea deep eutectic solvent (DES). We determine the electrochemically active surface area (ECSA) using lead underpotential deposition (UPD) to investigate the CO2RR intrinsic activity and selectivity. We show that the addition of Ag on electrodeposited Cu primarily suppresses the production of hydrogen and methane. While the production of carbon monoxide slightly increases, the partial current of the total C2+ products does not considerably increase. Despite that the production rate of C2+ is similar on Cu and Cu-Ag, the addition of Ag enhances the formation of alcohols and oxygenates over ethylene. We highlight the potential of metal electrodeposition from DES as a sustainable strategy to develop bimetallic Cu-based nanocatalysts for CO2RR.

Summary: Hydrodesulfurization (HDS) is a commonly used route for producing clean fuels in modern refinery. Herein, ammonium/amine-intercalated MoS2 catalysts with various content of 1T phase and S vacancies have been successfully synthesized. Along with the increment of 1T phase and S vacancies of MoS2, the initial reaction rate of the HDS of dibenzothiophene (DBT) can be improved from 0.09 to 0.55 μmol·gcat−1·s−1, accounting for a remarkable activity compared to the-state-of-the-art catalysts. In a combinatory study via the activity evaluation and catalysts characterization, we found that the intercalation species of MoS2 played a key role in generating more 1T phase and S vacancies through the ‘intercalation-deintercalation’ processes, and the hydrogenation and desulfurization of HDS can be significantly promoted by 1T phase and S vacancies on MoS2, respectively. This study provides a practically meaningful guidance for developing more advanced HDS catalysts by the intercalated MoS2-derived materials with an in-depth understanding of structure-function relationships.

Summary: Hydrogen generation from boron hydride is important for the development of hydrogen economy. Cobalt (Co) element has been widely used in the hydrolysis of boron hydride. Pyrolysis is a common method for materials synthesis in catalytic fields. Herein, Co-based nanocomposites derived from the pyrolysis of organic metal precursors and used for hydrolysis of boron hydride are summarized and discussed. The different precursors consisting of MOF, supported, metal, and metal phosphide precursors are summarized. The catalytic mechanism consisting of dissociation mechanism based on oxidative addition-reduction elimination, pre-activation mechanism, SN2 mechanism, four-membered ring mechanism, and acid-base mechanism is intensively discussed. Finally, conclusions and outlooks are conveyed from the design of high-efficiency catalysts, the characterization of catalyst structure, the enhancement of catalytic activities, the investigation of the catalytic mechanism, and the catalytic stability of active structure. This review can provide guidance for designing high-efficiency catalysts and boosting development of hydrogen economy.

Summary: Zeolite-encaged metal nanoparticles (NPs) catalysts are emerging as a new frontier owing to their superior ability to stabilize the structure and catalytic performance in the thermal and environmental catalytic reaction. However, the pore size below 2 nm of the conventional zeolites usually limits the accessibility of metal active sites. Herein, Co-Cu NPs of about 2.5–3.5 nm were uniformly encapsulated in the intracrystalline mesoporous Silicalite-1 (S-1) through alkali-treatment ligand-assisted strategy. The obtained sample (termed CoxCu1-x@HS-1) exhibited efficient activity and stability in the ammonia borane hydrolysis with the highest TOF value of 21.46 molH2·molMe−1·min−1. UV–vis DRS spectra indicated that intracrystalline mesopores have greatly improved the openness and accessibility of the active sites, thus improving their catalytic performance. The introduction of Cu regulates the electronic properties of Co, further increasing hydrogen production activity. This research creates new prospects to design other high-performance hierarchical porous zeolite-confined metal/metal oxide catalysts.

Summary: Acidic and basic sites of catalysts are essential for CO2 capture and activation. In this work, Zr, N-ZnO/ZnAl-LDH-IL composites in ionic liquid and methanol systems were fabricated, and applied to catalyze the synthesis of ethylene carbonate (EC) from ethylene glycol (EG) and CO2 with about 4.76 mmolEC gCat.−1 h−1. The composites showed more strong basic sites due to the effective induction of reactive groups on the catalyst surface by Zr doping, resulting in an increase of pyridinic-N groups from 5.48% to 22.25%. More C atoms adjacent to pyridinic-N as strong basic sites was conducive to the activation of CO2 and EG. In addition, the possible catalytic pathway and mechanism of the composites for synthesizing EC as well as the doping of La, Fe, Ce, and Cu were also investigated, which provides an effective strategy for regulating the acid-base centers on the catalyst surface through ionic liquids and methanol solvents.

Summary: Rechargeable lithium-ion batteries (LIBs) have prospered a rechargeable world, predominantly relying on various metal oxide cathode materials for their abilities to reversibly de-/intercalate lithium-ion, while also serving as lithium sources for batteries. Despite the success of metal oxide, issues including low energy density have raised doubts about their suitability for next-generation lithium batteries. This has sparked interest in metal chlorides, a neglected cathode material family. Metal chlorides show promise with factors like energy density, diffusion coefficient, and compressibility. Unfortunately, challenges like high solubility hamper their utilization. In this review, we highlight the opportunities for metal chlorides in the post-lithium-ion era. Subsequently, we summarize their dissolution challenges. Furthermore, we discuss recent advancements, encompassing liquid-state electrolyte engineering, solid-state electrolytes (SSEs) cooperation, and LiCl-based cathodes. Finally, we provide an outlook on future research directions of metal chlorides, emphasizing electrode fabrication, electrolyte design, the application of SSEs, and the exploration of conversion reactions.

Summary: Polyoxometalates (POMs) have been well studied and explored in electro/photochemical water oxidation catalysis for over a decade. The high solubility of POMs in water has limited its use in homogeneous conditions. Over the last decade, different approaches have been used for the heterogenization of POMs to exploit their catalytic properties. This study focused on a Keggin POM, K6[CoW12O40], which was entrapped in a sol-gel matrix for heterogeneous electrochemical water oxidation. Its entrapment in the sol-gel matrix enables it to catalyze the oxygen evolution reaction at acidic pH, pH 2.0. Heterogenization of POMs using the sol-gel method aids in POM’s recyclability and structural stability under electrochemical conditions. The prepared sol-gel electrode is robust and stable. It achieved electrochemical water oxidation at a current density of 2 mA/cm2 at a low overpotential of 300 mV with a high turnover frequency (TOF) of 1.76 [mol O2 (mol Co)−1s−1]. A plausible mechanism of the electrocatalytic process is presented.

Summary: Electrochromic (EC) glazing has garnered significant attention recently as a crucial solution for enhancing energy efficiency in future construction and automotive sectors. EC glazing could significantly reduce the energy usage of buildings compared to traditional blinds and glazing. Despite their commercial availability, several challenges remain, including issues with switching time, leakage of electrolytes, production costs, etc. Consequently, these areas demand more attention and further studies. Among inorganic-based EC materials, tungsten oxide nanostructures are essential due to its outstanding advantages such as low voltage demand, high coloration coefficient, large optical modulation range, and stability. This review will summarize the principal design and mechanism of EC device fabrication. It will highlight the current gaps in understanding the mechanism of EC theory, discuss the progress in material development for EC glazing, including various solutions for improving EC materials, and finally, introduce the latest advancements in photo-EC devices that integrate photovoltaic and EC technologies.

Summary: The production of high-demand syngas with tunable ratios by CO2 electroreduction has attracted considerable research interest. However, it is challenging to balance the evolution performance of H2 and CO with wide H2/CO ratios, while maintaining high efficiency. Herein, nitrogen-coordinated hierarchical porous carbon spheres with varying phosphorus content (PxNC-T) are assembled to regulate syngas production performance. The precise introduction of P modulates the local charge distribution of nitrogen-coordinated carbons, thereby accelerating the protonation process of ∗CO2-to-∗COOH and promoting moderate H∗ adsorption. Specifically, syngas with wide H2/CO ratios (0.60–4.98) is obtained over a low potential range (−0.46 to −0.86 V vs. RHE). As a representative, P1.0NC-900 presents a remarkable current density (−152 mA cm−2) at −1.0 V vs. RHE in flow cells and delivers a decent peak power density (1.93 mW cm−2) in reversible Zn-CO2 batteries. Our work provides valuable insights into the rational design of carbon-based catalysts for CO2 reduction.

Summary: Originally derived from graphite, high-quality single-layer graphene is an excellent anti-wear and -friction additive in metal matrix. Here, the tribological performance of 3 different commercialized graphene derivatives (e.g., graphene oxide [GO], reduced graphene oxide [RGO], and graphene nanoplatelet [GNP]) as additives in a Cu matrix, were investigated from an industrial perspective. To increase the interaction of graphene derivatives with Cu particles, and addressing the aggregation problem of the graphene derivatives, different binders (polyvinyl alcohol [PVA] and cellulose nanocrystals [CNC]) were introduced into the system. Benefiting from such a strategy, a uniform distribution of the graphene derivatives in Cu matrix was achieved with graphene loading up to 5 wt %. After high-temperature sintering, the graphene is preserved and well distributed in the Cu matrix. It was found that the GNP-containing sample shows the most stable friction coefficient behavior. However, GO and RGO also improve the tribological performance of Cu under different circumstances.

Summary: Abnormal accumulation of hydrogen peroxide (H2O2) in the tumor microenvironment is associated with altered metabolism, abnormal proliferation of tumor cells, and changes in the tumor microenvironment. Based on this phenomenon, we have developed manganese-doped zeolitic imidazolate frameworks (Mn-ZIF) nanozymes, which exhibit superior peroxidase (POD)-like activity and enhanced cytotoxicity. Inside the tumor, the H2O2 is catalyzed by Mn-ZIF nanozymes through the Fenton reaction to generate more potent hydroxyl radicals (·OH), further increasing the local reactive oxygen species (ROS) levels in tumor cells and inducing tumor cell death. Meanwhile, the removal of H2O2 in the tumor microenvironment reduces tumor proliferation. We have confirmed the anti-tumor effect of these particles in an in situ osteosarcoma (OS) model, providing a direction for the future design of hybrid nanozyme drug delivery systems.

Summary: Surface-supported metal−organic frameworks (SMOFs) are long-range ordered periodic 2D lattice layers formed by inorganic metal nodes and organic ligands via coordination bonds on substrate surfaces. The atomic resolution STM lays a solid foundation for the conception and construction of SMOFs with large area, stable structure, and special function. In this review, the cutting-edge research of SMOFs from design strategy, preparation process, and how to accurately achieve structural and functional diversity are reviewed. Furthermore, we focus on the design and construction of novel and fascinating periodic and fractal structures, in which some typical honeycomb structures, Kagome lattice, hexagonal geometry, and Sierpiński triangles are summarized, and the related prospects for designing functional nanoscale systems and architectures are prospected. Finally, the challenges faced in the design and synthesis of SMOFs are denoted, and the application prospect and development trend of SMOFs are forecasted based on the current research status.

Materials informatics employs data-driven approaches for analysis and discovery of materials. Features also referred to as descriptors are essential in generating reliable and accurate machine-learning models. While general data can be obtained through public and commercial sources, features must be tailored to specific applications. Common featurizers suitable for generic chemical problems may not be effective in features-property mapping in solid-state materials with ML models. Here, we have assembled the Oliynyk property list for compositional feature generation, which performs well on limited datasets (50 to 1000 training data points) in the solid-state materials domain. The dataset contains 98 elemental features for atomic numbers from 1 to 92, including thermodynamic properties, electronic structure data, size, electronegativity, and bulk properties such as melting point, density, and conductivity. The dataset has been utilized peer-reviewed publications in predicting material hardness, classification, discovery of novel Heusler compounds, band gap prediction, and determining the site preference of atoms using machine learning models including support vector machines, random forests for classification, and support vector regression for regression problems. We have compiled the dataset by parsing data from publicly available databases and literature and further supplementing it by interpolating values with Gaussian process regression.

Summary: Chitin is an abundant and renewable non-wood biopolymer. Nanochitin is formed by the assembly of chitin molecules, which has the advantages of large tensile strength, high specific surface area, and biodegradability, so it has been widely used. However, the traditional methods of preparing nanochitin have many drawbacks. As the new generation of green solvents, deep eutectic solvents (DESs) have been successfully applied in the fields of chitin dissolution, extraction, and nanochitin preparation. In this review, the relevant knowledge of chitin, nanochitin, and DESs was first introduced. Then, the application status of DESs in the fields of chitin was summarized, with a focus on the preparation of nanochitin using DESs. In conclusion, this review provided a comprehensive analysis of the published literature and proposed insights and development trends in the field of preparation of nanochitin using DESs, aiming to provide guidance and assistance for future researchers.

Summary: Electrocatalytic CO2 reduction reaction (CO2RR) has emerged as a focal point in sustainable energy research, offering the potential for closed carbon cycle. Among numerous catalysts designed for CO2RR, two-dimensional (2D) Cu-based catalysts stand out for their remarkable performance in efficiently converting CO2 into high-value-added C1 and C2+ chemicals. Herein, we discuss the recent progress and challenges in the realm of CO2RR utilizing 2D Cu-based catalysts. The first section introduces various synthetic strategies, emphasizing the features and advantages of different techniques and proposing solutions to existing challenges. The second part outlines the reaction mechanism underlying the production of C1 and C2+ products on Cu-based catalysts, then summarizes applications of different types 2D Cu-based catalysts in CO2RR. Additionally, we evaluate the limitations of 2D Cu-based catalysts and propose improved strategies. Through this exploration of research advances and challenges, we hope to illuminate the path toward developing excellent CO2 electrocatalysts.

Summary: Microplastic (MP) accumulation in the environment is accelerating rapidly, which has led to their effects on both the ecosystem and human life garnering much attention. This study is the first to examine the degradation of high-density polyethylene (HDPE) MPs via photoelectrocatalysis (PEC) using a TiO2-modified boron-doped diamond (BDD/TiO2) photoanode. This study was divided into three stages: (i) preparation of the photoanode through electrophoretic deposition of synthetic TiO2 nanoparticles on a BDD electrode; (ii) characterization of the modified photoanode using electrochemical, structural, and optical techniques; and (iii) degradation of HDPE MPs by electrochemical oxidation and photoelectrocatalysis on bare and modified BDD electrodes under dark and UV light conditions. The results indicate that the PEC technique degraded 89.91 ± 0.08% of HDPE MPs in a 10-h reaction and was more efficient at a lower current density (6.89 mA cm−1) with the BDD/TiO2 photoanode compared to electrochemical oxidation on bare BDD.

Per- and polyfluoroalkyl substances (PFAS) are increasingly appearing in drinking water sources globally. Our work focuses specifically on the adsorption of the legacy perfluorooctanoic acid (PFOA) using mesoporous hafnium oxide (MHO) ceramic synthesized via a sol-gel process. Experiments were performed at varying pH to determine the effect of surface charge on adsorption capacity of PFOA by MHO, and to postulate adsorption behavior. At pH 2.3, the adsorption capacity of PFOA on MHO was 20.9 mg/g, whereas at a higher pH of 6.3, it was much lower at 9.2 mg/g. This was due to increased coulombic attractions at lower pH between the positively charged conjugate acid active sites on MHO surface and negatively charged deprotonated PFOA anion in solution. After adsorption, the solid MHO was regenerated via calcination, reducing the amount of toxic solid waste to be disposed since the adsorbent is regenerated, and the PFOA is completely removed.

Li metal anodes are enticing for batteries due to high theoretical charge storage capacity, but commercialization is plagued by dendritic Li growth and short circuits when cycled at high currents. Applied pressure has been suggested to improve morphology, and therefore performance. We hypothesized that increasing pressure would suppress dendritic growth at high currents. To test this hypothesis, here, we extensively use cryogenic scanning electron microscopy to show that varying the applied pressure from 0.01 to 1 MPa has little impact on Li morphology after one deposition. We show that pressure improves Li density and preserves Li inventory after 50 cycles. However, contrary to our hypothesis, pressure exacerbates dendritic growth through the separator, promoting short circuits. Therefore, we suspect Li inventory is better preserved in cells cycled at high pressure only because the shorts carry a larger portion of the current, with less being carried by electrochemical reactions that slowly consume Li inventory.

The perspectives of technological advances needed for short term energetic transition are briefly reviewed and discussed critically. In particular, the technologies for the greenhouse gas emission-free production of electrical energy, its storage and transport, the production, transport, storage and use of hydrogen, and the use of biomass derived technologies are shortly and critically reviewed. Critical aspects are emphasized. The role of chemistry, and in particular materials chemistry and engineering, in short-term developments are underlined.

Summary: Rapid industrialization and untreated industrial effluents loaded with toxic and carcinogenic contaminants, especially dyes that discharge into environmental waters, have led to a rise in water pollution, with a substantial adverse impact on marine life and humankind. Photocatalytic techniques are one of the most successful methods that help in degradation and/or removal of such contaminants. In recent years, semiconductor quantum dots are being substituted by carbon dots (CDs) as photocatalysts, due to the ease of formation, cost-effectiveness, possible sustainability and scalability, much lower toxicity, and above all its high capacity to harvest sunlight (UV, visible, and near infrared) through electron transfer that enhances the lifetime of the photogenerated charge carriers. A better understanding between the properties of the CDs and their role in photocatalytic degradation of dyes and contaminants is required for the formation of controllable structures and adjustable outcomes. The focus of this review is on CDs and its composites as photocatalysts obtained from different sustainable green as well as chemical precursors. Apart from the synthesis, characterization, and properties of the CDs, the study also highlights the effect of different parameters on the photocatalytic properties of CDs and their composites for catalytic dye degradation mechanisms in detail. Besides the present research development in the field, potential challenges and future perspectives are also presented.

Summary: MXenes are promising materials for electrocatalysis due to their excellent metallic conductivity, hydrophilicity, high specific surface area, and excellent electrochemical properties. Herein, we summarize the recent advancement of MXene-based materials for electrocatalysis and highlight their key challenges and opportunities. In particular, this review emphasizes on the major design principles of MXene-based electrocatalysts, including (1) coupling MXene with active materials or heteroatomic doping to create highly active synergistic catalyst sites; (2) construction of 3D MXene structure or introducing interlayer spacers to increase active areas and form fast mass-charge transfer channel; and (3) protecting edge of MXene or in situ transforming the surface of MXene to stable active substance that inhibits the oxidation of MXene and then enhances the stability. Consequently, MXene-based materials exhibit outstanding performance for a variety of electrocatalytic reactions. Finally, the key challenges and promising prospects of the practical applications of MXene-based electrocatalysts are briefly proposed.

Summary: The biosilicification of diatoms allows for the customization of the synthesis of functionalized diatom frustules. The S active sites (–SH) on diatom frustules were created by adding the organic silicon sources tetramethoxysilane (TMOS) and (3-mercaptopropyl)trimethoxysilane (MPTMS). The mechanisms of adsorption-reduction and the indirect effects of S active sites on electrochemical performance were declared. The DBS@C-Ag-3 anode material sourced from the cultivation condition with a silicon source of TMOS:MPTMS = 3:1 shows the best comprehensive performance and delivers a discharge capacity of ∼660 mAh·g−1 after 1000 cycles at 1 A·g−1. The electrochemical performance of DBS@C-Ag anode materials is also found to be dominated by structure at high temperatures and conductivity at low temperatures. Such a diatom frustule structure with sulfhydryl functionalization is promising for anode materials, and it suggests a biological strategy for creating other electrode materials by modifying them with metals to improve electrochemical performances.

Summary: Herein, a hierarchical NiTe@NiFe-LDH core-shell array on Ni foam (NiTe@NiFe-LDH/NF) demonstrates its effectiveness for oxygen evolution reaction (OER) in alkaline seawater electrolyte. This NiTe@NiFe-LDH/NF array showcases remarkably low overpotentials of 277 mV and 359 mV for achieving current densities of 100 and 500 mA cm−2, respectively. Also, it shows a low Tafel slope of 68.66 mV dec−1. Notably, the electrocatalyst maintains robust stability over continuous electrolysis for at least 50 h at 100 mA cm−2. The remarkable performance and hierarchical structure advantages of NiTe@NiFe-LDH/NF offer innovative insights for designing efficient seawater oxidation electrocatalysts.

Summary: High-purity hydrogen produced by water electrolysis has become a sustainable energy carrier. Due to the corrosive environments and strong oxidizing working conditions, the main challenge faced by acidic water oxidation is the decrease in the activity and stability of anodic electrocatalysts. To address this issue, efficient strategies have been developed to design electrocatalysts toward acidic OER with excellent intrinsic performance. Electronic structure modification achieved through defect engineering, doping, alloying, atomic arrangement, surface reconstruction, and constructing metal-support interactions provides an effective means to boost OER. Based on introducing OER mechanism commonly present in acidic environments, this review comprehensively summarizes the effective strategies for regulating the electronic structure to boost the activity and stability of catalytic materials. Finally, several promising research directions are discussed to inspire the design and synthesis of high-performance acidic OER electrocatalysts.

Summary: The correlations between the experimental methods and catalytic activities are urgent to be defined for the design of highly efficient catalysts. In this work, a new oxygen evolution reaction electrocatalyst of high-entropy oxide (HEO) FeCoNiZrOx was designed and analyzed by experimental and theoretical methods. On account of the shortened coordinate bond along with the increased annealing temperature, the atomic/electronic structures of active site were adjusted quantitatively with the aid of the pre-designed correlator of d electron density, which contributed to adjust the catalytic activity of HEO specimens. The prepared HEO specimen exhibited the low overpotentials of 245 mV at 10 mA cm−2 and 288 mV at 100 mA cm−2 with small Tafel slope of 35.66 mV dec−1, fast charge transfer rate, and stable electrocatalytic activity. This strategy would be adopted to improve the catalytic activity of HEO by adjusting the d electron density of transition metal ions with suitable preparation method.

Summary: Electrocatalytic carbon dioxide reduction reaction (CO2RR) is a newly developed strategy for energy conversion and carbon neutrality, which can achieve both valuable fuel generation and sustainable carbon cycles. Constructing well-defined, two-dimensional (2D) materials with abundant active sites and significant tunability is suitable for catalyst selections for the CO2RR. In this review, we first briefly introduce the fundamental information of the CO2RR and 2D materials. Then, the advantages of different types of 2D catalysts for electrocatalytic conversion of CO2 into value-added chemicals and fuels were emphasized. After that, several emerging strategies for tailoring 2D materials to enhance electrocatalytic performance were discussed and summarized systemically. Finally, the remaining challenges and prospects were also presented with optimization proposals for the possible applications of 2D materials as highly efficient nanoelectrocatalysts for CO2RR in the future.

Summary: Wood, with its inherent hierarchical structure, presents opportunities for creating eco-friendly and cost-effective alternatives to petroleum-based plastics. We introduced a top-down and polymer-free method for engineering natural balsa wood into transparent wood film, demonstrating its potential use in food packaging windows. The wood was delignified and then proceeded with 2,2,6,6-tetramethyl-1-piperidinyloxy oxidation to soften the wood structure and introduce carboxyl groups. A robust and transparent wood film was produced by drying the wood under ambient condition without the need for additional polymers or mechanical force. Curcumin was also integrated into the wood using vacuum impregnation. The functionalized wood film with curcumin (WFC) exhibited a distinguishable redness shift in alkaline conditions. We then applied the WFC as an intelligent food packaging window to sense the freshness of shrimp based on the pH-responsive color change. This study provides a simple and scalable approach for developing sustainable and smart food packaging using wood.

Summary: Layered double hydroxides (LDHs) are widely used in catalytic field, especially in photocatalysis, benefiting from the ultrathin 2D structure and luxuriant surface functional groups. However, the wide band gap and low utilization rate of solar spectrum affect their photocatalytic performance. Herein, we integrated n-type CoAl-LDH with p-type Cu2O nanoparticles to construct a p-n heterojunction with a strong built-in electric field, which can prevent photoinduced electron-hole pairs from recombination as well as facilitate charge transfer. With the X-ray photoelectron spectroscope and in situ Fourier transform infrared spectroscopy, we confirmed the charge transfer under light illumination complying with the type II-scheme mechanism and analyzed the intermediates during photocatalytic CO2 reduction reaction (CO2RR). The highest yields reached 320.9 μmol h−1 g−1 for CoAl-LDH@Cu2O-60 (LC-60) under 1 h light irradiation, which was about 1.6 times than the pristine CoAl-LDH. The sample also exhibited excellent stability which maintained 84.1% of initial performance after 4 circulations.

Summary: Since the discovery of graphene in 2004, two-dimensional (2D) materials have attracted widespread attention due to their excellent physical and chemical properties in the fields of energy, environment, catalysis, and optoelectronics. However, there are still many key problems in the process of practical application. To further promote the potential of 2D materials for practical applications, macroscopic assembly of 2D materials is crucial for the continued development of 2D materials, especially in the fields of energy storage and seawater desalination. Therefore, this review focuses on the latest progress and current status related to the macroscopic assembly of 2D materials, including 1D fibers, 2D films, and 3D architectures. In addition, the application of macroscopic bodies assembled based on 2D materials in the fields of energy storage and seawater desalination is also introduced. Finally, future directions for the macroscopic assembly of 2D materials and their applications are prospected.

The development of nanotechnology has provided an opportunity to integrate a wide range of phenomena and disciplines from the atomic scale, the molecular scale, and the nanoscale into materials. Nanoarchitectonics as a post-nanotechnology concept is a methodology for developing functional material systems using units such as atoms, molecules, and nanomaterials. Especially, molecular nanoarchitectonics has been strongly promoted recently by incorporating nanotechnological methods into organic synthesis. Examples of research that have attracted attention include the direct observation of organic synthesis processes at the molecular level with high resolution, and the control of organic syntheses with probe microscope tips. These can also be considered as starting points for nanoarchitectonics. In this review, these examples of molecular nanoarchitectonics are introduced, and future prospects of nanoarchitectonics are discussed. The fusion of basic science and the application of practical functional materials will complete materials chemistry for everything.