Lithium–sulfur (Li–S) batteries are severely hindered by the low sulfur utilization and short cycling life, especially at high rates. One of the effective solutions to address these problems is to improve the sulfiphilicity of lithium polysulfides (LiPSs) and the lithiophilicity of the lithium anode. However, it is a great challenge to simultaneously optimize both aspects. Herein, by incorporating the merits of strong absorbability and high conductivity of SnS with good catalytic capability of ZnS, a ZnS-SnS heterojunction coated with a polydopamine-derived N-doped carbon shell (denoted as ZnS-SnS@NC) with uniform cubic morphology was obtained and compared with the ZnS-SnS2@NC heterostructure and its single-component counterparts (SnS@NC and SnS2@NC). Theoretical calculations, ex situ XANES, and in situ Raman spectrum were utilized to elucidate rapid anchoring-diffusion-transformation of LiPSs, inhibition of the shuttling effect, and improvement of the sulfur electrochemistry of bimetal ZnS-SnS heterostructure at the molecular level. When applied as a modification layer coated on the separator, the ZnS-SnS@NC-based cell with optimized lithiophilicity and sulfiphilicity enables desirable sulfur electrochemistry, including high reversibility of 1149 mAh g–1 for 300 cycles at 0.2 C, high rate performance of 661 mAh g–1 at 10 C, and long cycle life with a low fading rate of 0.0126% each cycle after 2000 cycles at 4 C. Furthermore, a favorable areal capacity of 8.27 mAh cm–2 is maintained under high sulfur mass loading of 10.3 mg cm–2. This work furnishes a feasible scheme to the rational design of bimetal sulfides heterostructures and boosts the development of other electrochemical applications.

Herein, a mini review is presented concerning the most recent research progress of carbon nanodots, which have emerged as one of the most attractive photoluminescent materials. Different synthetic methodologies to achieve advanced functions and better photoluminescence performances are summarized, which are mainly divided into two classes: top-down and bottom-up. The inspiring properties, including photoluminescence emission, chemiluminescence, electrochemical luminescence, peroxidase-like activity and toxicity, are discussed. Moreover, the biomedical applications in biosensing, bioimaging and drug delivery are reviewed.

Ordered 2D non-close-packed sphere arrays with controllable lattice structures have been fabricated by using soft lithography based on the solvent-swelling and mechanical deformation behaviors of PDMS film. The figure shows an SEM image of the ordered quasi-one-dimensional parallel wires of silica spheres on a polymer-coated substrate.

Aptamers have been widely used as recognition elements for biosensor construction, especially in the detection of proteins or small molecule targets, and regarded as promising alternatives for antibodies in bioassay areas. In this review, we present an overview of reported design strategies for the fabrication of biosensors and classify them into four basic modes: target-induced structure switching mode, sandwich or sandwich-like mode, target-induced dissociation/displacement mode and competitive replacement mode. In view of the unprecedented advantages brought about by aptamers and smart design strategies, aptamer-based biosensors are expected to be one of the most promising devices in bioassay related applications.