Materials Chemistry Frontiers最新文献

Pd-based catalytic electrodes for the hydrogen evolution reaction (HER) are promising as a replacement of Pt-based catalysts, but their strong hydrogen adsorption hinders hydrogen desorption and thus limits HER catalytic activity. Here, we report a function–structure integrated D-Ni_3.5Pd/NF catalytic electrode with a very low Pd loading (0.19 mg_Pd cm⁻²) and a large number of edge dislocations, which was prepared by millisecond laser direct writing in liquid nitrogen. The plentiful dislocations induce a strain effect leading to reduced hydrogen adsorption energies of Pd sites and enhanced water dissociation ability of Ni sites. Thereby, the dense dislocations improve the alkaline HER intrinsic activity and electrochemical stability of D-Ni_3.5Pd/NF under high current densities. The as-prepared electrodes can achieve fairly low overpotentials of 35 and 352 mV at 10 mA cm⁻² and 1 A cm⁻² in a 1 M KOH electrolyte, respectively, while the Tafel slope is only 62.3 mV dec⁻¹. In addition, its overpotential only increases by 4.2% after 100 h of the chronoamperometric test at 500 mA cm⁻², showing an outstanding electrochemical stability at high current densities.

Water splitting is an essential process for renewable energy systems, requiring efficient, economical, and abundant catalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Phase engineering of nanomaterials (PENs) has emerged as a promising strategy to optimize catalytic activity. Unconventional phases have been discovered in various nanomaterials, including metals, metal oxides, transition metal phosphides, and chalcogenides, making PENs a viable approach to catalyst design. The corresponding catalysts have exhibited distinctive HER and OER performances. However, the phase engineering of the iron group transition metal selenides (IGTMSes) for water splitting is still under development and needs systematic summarization. To assist researchers in understanding the trends in controllable phase engineering of IGTMSes for water splitting, this review provides detailed explanations of various PEN methods and traditional phase transition strategies.

Metal clusters (MCs), a special species of ultrafine metal nanoparticles with dimensions below 2 nm, serve as highly active catalysts for a broad spectrum of chemical reactions, but usually suffer from serious aggregation due to their high surface energy. A balance between the activity and stability of MCs is greatly challenging in designing efficient catalysts. Cage-bearing materials such as organic molecular cages and metal–organic cages, as another promising category of porous materials, are attracting significant research attention. Thanks to their intrinsic cavity, such materials can serve as ideal confined templates for the size-controlled synthesis of MCs without blocking their active sites. Moreover, benefiting from the easy-to-modify architecture, the cage polyhedrons can be further functionalized to obtain advanced composite catalysts in combination with the hosted MCs. As such, the multiple active sites are spatially organized and compartmentalized by the cage skeleton, which therefore avoids undesired mutual quenching. With the synergy of multi-catalytic centers, the integrated cage-bearing nanocomposite catalysts have advanced as another burgeoning candidate to perform accurate and efficient multistep cascade reactions by mimicking cell metabolism and biological synthesis. In this review, we will introduce the most recent adopted confined synthetic methodologies for MCs enabled by cage materials on the one hand, and their applications in advanced catalysis on the other hand.

Carbohydrates are of great importance in a variety of biological processes, including but not limited to, energy production, energy storage, protein recognition, immune response, and macromolecule decoration. Many of the biofunctions of carbohydrates are achieved through a multivalent effect, so the construction of a multivalent carbohydrate system has remained an important topic in glycobiochemistry. Supramolecular macrocycles are characterized by an adjustable cavity, controllable conformation, precise structure, modifiability, and a pre-organized structure. Combined with their recognition and assembly properties, supramolecular macrocycles play an important role in the field of biomedical materials. This review focuses on the synthesis of such conjugates and discusses the biofunctions of carbohydrates and macrocycles, the synergetic contribution of the conjugates, and the perspectives of carbohydrate–macrocycle conjugates.

Nanomaterials are the wonder materials in many distinguished fields, yet their research in mainstream lithium-ion batteries is at initial stages. Polyanion-based cathode materials use nanostructuring to enhance their performance throughput, yet due to several property mismatches, the transition metal oxide system still lags in adapting nanomaterials. Due to such slow-paced development reason, this review addresses accumulated knowledge on transition metal oxide nanomaterial synthesis and their performance in applications as cathode materials in Li-ion batteries. Through this work, we aim to provide researchers with knowledge such as the present challenges to overcome and vast opportunities for working with nanomaterials as cathodes for next-generation Li-ion batteries.

Polymeric nanomaterials with aggregation-induced emission (AIE) characteristics have attracted significant attention from the scientific community because of their extensive biomedical applications. Nanoparticles prepared from AIE materials possess favorable advantages over fluorescent molecular dyes, including higher photostability, brightness, turn-on emission, easy functionalization, and tunable size/topology. In this review, we systematically summarize the preparation strategies of various polymeric AIE nanomaterials, including the encapsulation method, free-radical copolymerization, controlled radical polymerization, click polymerization, supramolecular assembly, and post-polymerization reactions. Some special polymer topologies, such as star-shaped, crosslinked, and 2D polymers, are discussed in detail. Last but not least, perspectives on AIE polymeric nanomaterials are provided to stimulate future development.

Thermoelectric (TE) materials are auspicious candidates for direct thermal–electrical energy conversion applications. Interface engineering is one of the key parameters to determine the physicochemical properties of nanocomposites, in which interfacial manipulation can reduce κ by nano/micro-scale grain boundary construction and increase the power factor by electronic structure modifications, ultimately leading to an increase in ZT. With the advancement of nanotechnology, the design and synthesis of nanoparticles can be extended to sub-nanometer and even single-atom scales, which provides an opportunity for developing novel materials with extraordinary thermoelectric performances. In this article, we have chosen a completely new field – interface and provide a comprehensive review of the interfacial manipulation of hybrid materials, which are discussed in four parts chosen according to their dimension forms, including atoms, nanoclusters, ligand molecules, and particles. We also analyze the interaction of nanoparticle surfaces and identify the possibilities and obstacles for improving the performance of TE materials.

Metal–organic frameworks (MOFs) are a class of solid crystalline materials formed by the self-assembly of organic ligands and metal ions or clusters through coordination bonds. Owing to their intrinsic rich chemical composition, large specific surface area, diverse topology, tunable pore channels and good thermal stability, MOFs are favored in many applications. In particular, MOFs are considered to be viable membrane-based separation materials based on their unique advantages in the adsorption of specific chemicals. Research into MOF-based membrane-preparation methods and separation applications is flourishing, and MOF-based membranes have achieved marvellous achievements in the field of gas separation and liquid separation. This review first introduces the general criteria for selecting MOFs for separation applications. Then, we specifically describe how to prepare MOF-based membranes as well as the specific classification of MOF hybrid membranes, and finally describe the application of MOF-based membranes in water treatment. Most of all, the opportunities and challenges of MOF membranes in industrial applications are outlined.

A universal plasma-assisted strategy is proposed for the fabrication of rare earth (RE)-doped FeP nanorod arrays (RE-FeP) as a kind of potential electrocatalyst for the hydrogen evolution reaction (HER). The energetic Ar plasma can induce the vacancy-enriched feature of the Fe-precursor, which assists in the anchoring of RE ions. As a typical model, Sm-FeP affords a low overpotential of 71 mV at 10 mA cm⁻² for the HER, which is 63 mV smaller than that of FeP and superior to most reported Fe-based catalysts. The robust long-term stability of Sm-FeP is also demonstrated. Furthermore, the as-assembled Sm-FeP‖RuO₂ water-splitting electrolyzer also displays a low cell voltage of 1.59 V at 10 mA cm⁻². Sm-induced electronic configuration modulation at the Fe site mainly contributes to the improved HER performance of Sm-FeP relative to FeP. The combination between the Sm site and *OH produces labile O 2p states below the Fermi level, thus weakening the co-adsorption of *OH and *H derived from the splitting of H₂O for the facilitated formation of *H. Moreover, the other RE-FeP catalysts (e.g., Yb, Eu, La, and Er) extended by such a plasma-induced strategy also exhibit various improved degrees in the HER, implying that RE-FeP is a promising class of electrocatalyst towards the HER.