Reviews & Analysis

Fluorescent diarylethenes are the most attractive molecules for several applications, such as optical memories, optical switches, or probes for the imaging technology. A wide variety of fluorescent diarylethenes combining with organic fluorophores, emissive polymers, or fluorescent inorganic materials have been developed from the molecular level to the nanoscale during the past decade. In this review, the different molecular and nanomaterial designs providing suitable fluorescence photoswitching property are introduced. Furthermore, the recent development of new applications using fluorescent diarylethene-based molecules and nanomaterials are also summarized.

With the rapid development of nanotechnology, the unique rare earth lanthanide-doped upconversion nanocrystals (UCNs), which can convert tissue-penetrable near-infrared (NIR) photonic irradiation into ultraviolet, visible and NIR emissions, have found significant potential in bioimaging, diagnosis, therapy, as well as photovoltaics and optical data storage. Despite the promising achievements made in the past decade, critical challenges associated with low upconversion efficiencies and overheating effect induced by NIR laser-irradiation remain in the biomedical fields. More well-defined material design and unique structural modification are highly demanded that are capable of solving these technical concerns and promoting such promising NIR light mediated upconversion nanocrystals for their further practice in medical sciences. Recent advances in upconversion nanomaterials have witnessed the tremendous development towards enhancing the photon converted efficiency, which provides great opportunities in expanding the UCNs potential in bioimaging diagnosis and anticancer therapy. Hence, this review is mainly focusing on summarizing the fundamental principles and strategies to improve the upconversion luminescence and the approaches to reduce the local thermal effect on the basis of rational design of UCNs. In addition, the future perspectives in the development of UCNs for biomedical applications are also proposed.

In this article, we review the prototypical phase-transition material-VO₂, which undergoes structure and conductivity changes simultaneously. The recent progresses in the transition mechanism are also discussed. Besides, this work gives a comprehensive understanding of the phase-transition modulations, such as element doping, electric field (current and gating) and tensile/compression strain, as well as employing laser.

Advanced in situ/operando synchrotron based X-ray characterization techniques are powerful tools in providing valuable information about the complicate reaction mechanisms in lithium-ion batteries. In this review, the state-of-the-art of in situ/operando synchrotron-based X-ray techniques and their combination for battery research are introduced. Various types of in situ cell designs and practical operation tips for experimental set ups are also discussed.

This review recapitulates some of the most representative studies recently reported on carbon-supported catalysts for the hydrogen production from formic acid and ammonia borane by considering both active phase features and support properties. Several synthetic strategies are herein summarized to highlight the versatility of carbon materials in affording highly-performing catalysts for the hydrogen production from hydrogen carrier molecules.

Graphene has received enormous research interest in recent years owing to its intriguing structure and fascinating properties. Its high mechanical strength, flexibility and optical transparency make it a desire building block of 2D Janus materials. Through asymmetric surface modifications on target graphene derivatives, including hydrogenation and halogenation, grafting of organic molecules and polymers, and deposition of metal/metal oxides, different graphene-based Janus materials have been achieved with various shapes, sizes, and compositions. This review presents and discusses the development, fabricating strategies and applications of these 2D Janus materials, starting with the theoretical understanding of the behavior of Janus graphene.

Exploration of noncovalent interactions of such as H-bonding, p-stacking and van der Waals forces to the design of hybrid materials of 1D or 2D carbon allotropes and synthetic p-systems such as aromatic small molecules, gelators and polymers for various applications ranging from materials to biology are discussed.

A target of this review is soft 2D nanoarchitectonics because scientific views on soft 2D nanomaterials are not fully established as compared with rigid 2D materials. The presented examples are selected according to the following three categories on the basis of 2D spatial density and motional freedoms: (i) well-packed and oriented organic 2D materials with rational design of component molecules and device applications, (ii) well-defined assemblies with 2D porous structures as 2D network materials, and (iii) 2D controls of molecular machines and receptors on the basis of certain motional freedom with confined nature in 2D plain.

In this paper, the design strategy of trivalent lanthanide (Ln(III)) complexes for effective photo-, electric-, and tribo-sensitized luminescence are reviewed. Ln(III) complexes with well-designed organic molecules are expected to open up a frontier field of chemistry, physics, electronics and material science.

In this review, we overview the recent achievements in synthesis of high performance nacre-inspired macroscopic composites and divide them into different groups by standards of different dimensions, such as 1D nacre-inspired fibers, 2D nacre-inspired films and 3D nacre-inspired bulk composites. The methods to produce different dimensional nacre-inspired composites are also introduced and performance enhanced strategies for different dimensional nacre-inspired composites are summarized and explained in detail. Applications of high mechanical performance nacre-inspired composites are also summarized. A critical outlook for next-generation light-weight and high performance materials is proposed.

In this review, we highlight the recent progress in two rising areas: solar energy conversion through plasmon-assisted interfacial electron transfer and plasmonic nanofabrication. Localized surface plasmon resonance (LSPR) of plasmonic nanoparticles and nanostructures has attracted increasing attention because of their strong near-field enhancement by interacting with visible light. Recent studies have demonstrated the capability of such plasmonic systems in producing ‘LSPR-induced hot-electrons’ that are useful in photoenergy conversion and storage when combined with electron-accepting semiconductors. Concurrently, ‘hot-electron decay’ results in strong photothermal responses or plasmonic local heating. This heating has received renewed interest in photothermal manipulation of nanoparticles and molecules.

Schematic illustration of Biomaterial Strategies for Controlled Growth Factor (GF) Delivery for Biomedical Applications. (a) The direct approaches for the immobilization/encapsulation of GFs to biomaterials; (b) Nanocarriers for GFs encapsulation and release; (c) GFs encapsulated nanocarriers functionalized biomaterials for tissue regeneration.

Fluorine, the element with the highest electronegativity and low electric polarizability, can produce a variety of characteristics, including specific adsorption sites for molecules as well as flexibility to the host materials. In this review, we will introduce fluorine-functionalized metal–organic frameworks/porous coordination polymers that show unique and unprecedented structures, structural transformations, and gas and vapor adsorption/separation properties derived from the fluorine characteristics.

Graphene nanomaterials hold great promise for the development of advanced water purification membranes, especially for water desalination. Their atomic thickness, extraordinary mechanical stability and potential for size-selective transport are ideal features, encouraging the membrane scientist across the world to investigate their applicability for water desalination. Graphene can potentially desalinate water either as monolayer or as multilayer membranes. In this review, we discuss these different classes of graphene membranes and highlight their merits and shortcomings. In addition, the theory behind their performance is presented in detail.

Formed by the self-assembly of protein subunits, protein nanocages can be engineered at the interior, exterior, and inter-subunit locations. Each type of modification can be tuned for specific biological applications. Multiple-modifications can be imparted to these nanocages without compromising its self-assembling property, creating multi-functional protein nanocage platforms. Potential applications of the modified protein nanocages include targeted delivery in complex cellular environments for therapeutic and diagnostic agents as well as modulation of cellular responses.

This review summarizes recent results on the syntheses and characterization of the non-native phases of h-CoO, h-MnO and c-ZnO transition metal monoxides compared to their native phases. The investigation of the size- and phase-selective synthetic methods, formation mechanism and unique physicochemical properties of non-native transition metal monoxides would have an enormous impact on materials chemistry and open a promising avenue for magnetic, electronic, and spintronic applications.

The microstructure dynamics of electrode materials during battery cycling is dictated by the coupling between their lattice, charge and orbital characteristics, as shown in the schematic. TEM monitoring enables tracking lattice and chemical bonding at high spatial resolution, and thereby establishes the relationship between structure and performances.

This review summarizes recent developments in the direct synthesis and ion exchange-based reactions leading to hybrid organic–inorganic and all-inorganic lead halide perovskite nanocrystals. Optical properties related to quantum confinement effects, single emission spectroscopy and lasing are considered. Perovskite nanocrystals have been employed as an active material in several applications such as light-emitting devices, solar cells and photodetectors.

A huge interest shows that optical contrast agents to probe biological specimen both functionally and structurally with deeper action depth and better spatial resolution is closely related with the development of near-infrared (NIR) light excitation and nonlinear optics and new imaging methods. This review will go beyond the state-of-the-art by revisiting the up-to-date progress in developing smart NIR-to-NIR and upconverted nanomaterials for in vivo bioapplications. The latest advances in the development of novel NIR-to-NIR linear and nonlinear optical nanomaterials and their potential applications in cancer targeting, diagnosis and therapeutics and deep-tissue imaging are described.

PHAs are natural biodegradable polyesters synthesized by microorganisms. However, several disadvantages such as their poor mechanical properties and limited functionalities limit their competition with traditional synthetic plastics or their application as ideal biomaterials. To circumvent these drawbacks, PHAs need to be modified to ensure improved performance in specific applications. Well-established modification methods of PHAs are summarized and discussed. The improved properties of PHA that blends with natural raw materials or other biodegradable polymers are summarized. The functionalization of PHAs by block copolymerization and graft copolymerization is described. The expanded utilization of the modified PHAs as (bio)engineering materials is addressed.