Reviews & Analysis

Since the first report in 1970s, W–Cu composites have attracted extensive attentions owing to their outstanding integrated properties of high hardness, wear resistance and electrical conductivity and low thermal expansion coefficient. This article reviewed recent important progress in the fields of preparation, microstructural characterization, and mechanical and physical properties of W–Cu composites. Particularly, new technologies for microstructure refinement and strategies to enhance the comprehensive performance were summarized and evaluated. The future promising research issues, which may break though the bottleneck of existing performance level of W–Cu composites and facilitate the development of other refractory/non-ferrous metals based nanocomposites, were proposed.

The inability to administer oxygen in a controlled and sustained manner into thick artificial tissues has attracted a growing interest towards the design and development of new functional biomaterials. Without a sufficient oxygen supply, tissues suffer from the effects of apoptosis and necrosis. Incorporation of oxygen-releasing materials into scaffolds can help address this challenge. This paper provides an overview of the recent developments and technological advances in engineering oxygen-releasing biomaterials to improve the viability and function of cells and prevent hypoxic tissue death. Recent advances in different types of oxygen-releasing materials, mechanisms of oxygen generation, and their applications are discussed.

Stimulus-responsive hydrogels, with biocompatibility, sufficient water content, similarity to extracellular matrices, and responses to specific environmental stimuli, have recently received massive research interest for fabricating bioactuators. The potential of employing these hydrogels that respond to various stimuli (e.g., pH, temperature, light, electricity, and magnetic fields) for actuation purposes has been uncovered by their performances in biosensing, drug delivery, artificial muscle reconstruction, and cell microenvironment engineering. In this review, a material selection of stimulus-responsive hydrogels and a detailed discussion of recent advances in emerging biomedical applications of hydrogel-based bioactuators are proposed. Existing challenges and future prospects are noted as well.

Overview of up-conversion based condensed phase laser cooling of semiconductor nanostructures. Two critical parameters dictate the likelihood of realizing solid state optical refrigeration: nanostructure emission quantum yield and up-conversion efficiency. This review summarizes both parameters for existing high emission quantum yield semiconductor nanostructures such as CdSe and CsPbBr₃. CsPbBr₃ nanocrystals, in particular, possess optimal parameters for cooling, namely near unity emission quantum yields and up-conversion efficiencies up to 75%. This makes them promising materials for verifiable demonstrations of condensed phase laser cooling.

Mass spectrometry, coupled with soft ionization methods, in conjunction with associated techniques such as tandem mass spectrometry, ion mobility and spectroscopies of sorts, has become a powerful tool for the characterization of advanced materials.

Surface-grafting polymer brush (SPB) technique can be used to change the inherent physical/chemical properties of materials surface. Practical applications are paid more attention since SPB technique enables to decorate materials with diverse functions. This paper reviews the current grafting strategies to generate polymer brush layer on surface of solid materials with diverse geometric structures/sizes, and then systematically summarizes the recent research advances on application of polymer brushes-modified materials. Correspondingly, some key challenges of SPB technique with considering its real application in future are discussed. The aim to draft this paper is to tell the readers how to engineer functional materials by SPB technique.

The past decade has witnessed substantial advances in the synthesis of various electrode materials with three-dimensional (3D) ordered macroporous or mesoporous structures (the so-called “inverse opals”) for applications in electrochemical energy storage devices. Yuping Wu from Nanjing Tech University anchored recent advancements in 3D ordered porous (3DOP) electrode materials and their unusual electrochemical properties bound by their intrinsic and geometric structures. The team introduces various 3DOP electrode materials and their representative applications as electrode materials. Additionally, the team also provides research opportunities as well as the challenges to facilitate further contributions to this emerging research frontier.