DJL

Ba₆Zn₆ZrS₁₄ was synthesized by a traditional salt-melt method with KI as flux. The pale yellow crystals of Ba₆Zn₆ZrS₁₄ crystallize in the tetragonal space group I4/mcm with a=16.3481 (4) Å and c=9.7221(6) Å. The structure features unique one-dimensional parallel [Zn₆S₉]⁶⁻ and [ZrS₅]⁶⁻ straight chains. The D_2h-symmetric [Zn₆S₉]⁶⁻ cluster serves as the building block of the [Zn₆S₉]⁶⁻ chains. A powder sample was investigated by X-ray diffraction, optical absorption, and photoluminescence measurements. The compound shows multiple-absorption character with three optical absorption edges around 1.78, 2.50, and 2.65 eV, respectively, which are perfectly consistent with the results of first-principles calculations. Analysis of the density of states further revealed that the three optical absorption bands are attributable to the three S(3p⁶)→Zr(4d⁰) transitions due to the splitting of the Zr 4d orbitals in the D_4h crystal field. The multiband nature of Ba₆Zn₆ZrS₁₄ also results in photocatalytic activity under visible-light irradiation and three band-edge emissions.

Bandgap engineering: ZnS- and ZrS-based building blocks were combined to construct multicomponent material Ba₆Zn₆ZrS₁₄, which features two types of one-dimensional chains parallel to the c axis and shows a much more complex absorption character than simple ZnS and ZrS₂ materials, with three optical absorption edges around 1.78, 2.50, and 2.65 eV (see figure).

The bandgaps of monolayer and bulk molybdenum sulfide (MoS₂) result in that they are far from suitable for application as a saturable absorption device. In this paper, the operation of a broadband MoS₂ saturable absorber is demonstrated by the introduction of suitable defects. It is believed that the results provide some inspiration in the investigation of two-dimensional optoelectronic materials.

A novel way to tune the bandgap in an Ag₂S quantum dot (QD) system is developed by inducing a lattice-distorted region of ≈1-nm scale in a QD with rapid quenching. Accordingly, the bandgap can be controlled simply by tailoring the degree of the lattice-distortion in a QD (2.51 to 1.64 eV). As reported by H. M. Jang and co-workers on page 1300, this conceptual method can pave a new way to realize quantum effects in future QD-based applications.

The miniaturization of power sources aimed at integration into micro- and nano-electronic devices is a big challenge. To ensure the future development of fully autonomous on-board systems, electrodes based on self-supported 3D nanostructured metal oxides have become increasingly important, and their impact is particularly significant when considering the miniaturization of energy storage systems. This review describes recent advances in the development of self-supported 3D nanostructured metal oxides as electrodes for innovative power sources, particularly Li-ion batteries and electrochemical supercapacitors. Current strategies for the design and morphology control of self-supported electrodes fabricated using template, lithography, anodization and self-organized solution techniques are outlined along with different efforts to improve the storage capacity, rate capability, and cyclability.

The role of electrodes based on self-supported 3D nanostructured metal oxides is important in energy storage and conversion. This article introduces readers to the concept of self-supported 3D electrodes and the advantages of these electrodes have over current designs, along with the common methods of fabrication and potential applications, such as 3D Li-ion microbatteries and supercapacitors.

Hybrid nanomaterial based on quantum dots and SWCNTs is used for cellular imaging and photothermal therapy. Furthermore, the ligand conjugated hybrid system (FaQd@CNT) enables selective targeting in cancer cells. The imaging capability of quantum dots and the therapeutic potential of SWCNT are available in a single system with cancer targeting property. Heat generated by the system is found to be high enough to destroy cancer cells.

Creating artificial enzymes that mimic the complexity and function of natural systems has been a great challenge for the past two decades. In this Progress Report, the focus is on recently discovered “hidden talents” of gold nanomaterials in artificial enzymes, including mimicking of nuclease, esterase, silicatein, glucose oxidase, peroxidase, catalase, and superoxide dismutase. These unexpected enzyme-like activities can be ascribed to nano-gold itself or the functional groups present on surrounding monolayer. Along with introducing the mechanisms of the various enzyme-like activities, the design and development of gold-based biomimetic catalysts, the search for efficient modulators, and their potential applications in bionics, biosensing, and biomedical sciences are highlighted. Eventually, it is expected that the rapidly growing interest in gold-based nanozymes will certainly fuel the excitement and stimulate research in this highly active field.

A significant challenge in chemistry is to create synthetic structures that mimic the complexity and function of natural systems. In this Progress Report, recent progress for enzyme-like catalytic activities based on gold nanomaterials is introduced. The work covers catalytic mechanisms, design and development, and potential applications of these catalysts. Additionally, the perspectives on future opportunities and current challenges are also discussed.

We report ambipolar charge transport in α-molybdenum ditelluride (MoTe₂) flakes, whereby the temperature dependence of the electrical characteristics was systematically analyzed. The ambipolarity of the charge transport originated from the formation of Schottky barriers at the metal/MoTe₂ contacts. The Schottky barrier heights as well as the current on/off ratio could be modified by modulating the electrostatic fields of the back-gate voltage (V _bg) and drain-source voltage (V _ds). Using these ambipolar MoTe₂ transistors we fabricated complementary inverters and amplifiers, demonstrating their feasibility for future digital and analog circuit applications.

Stabilization of protein–protein interactions by small molecules is a concept with few examples reported to date. Herein we describe the identification and X-ray co-crystal structure determination of IBE-667, an ICAM-1 binding enhancer for LFA-1. IBE-667 was designed based on the SAR information obtained from an on-bead screen of tagged one-bead one-compound combinatorial libraries by confocal nanoscanning and bead picking (CONA). Cellular assays demonstrate the activity of IBE-667 in promoting the binding of LFA-1 on activated immune cells to ICAM-1.

Tuned up: The LFA-1 ICAM-1 interaction is a fundamental step in T-cell activation in response to antigen encounter. A small-molecule activator of LFA-1, IBE-667, was identified by confocal on-bead screening. The identified activator binds to LFA-1 I domain, as revealed by the co-crystal structure, and increases the affinity of LFA-1 for ICAM-1 on activated T-cells.

“My greatest achievement is hopefully still to come from an unexpected observation. I lose track of time whenever I'm playing Bach …” This and more about Nuno Maulide can be found on page 7984.