Efficient water splitting through electrocatalysis holds great promise for producing hydrogen fuel in modern energy devices. Its real application however suffers from sluggish reaction kinetics due to the lack of high-performance catalysts except noble metals such as platinum. Herein, we report an active system of plasmonic-metal Au nanorods/molybdenum disulfide (MoS2) nanosheets hybrids for the hydrogen evolution reaction (HER). The plasmonic Au-MoS2 hybrids dramatically improve the HER, leading to a ∼3-fold increase of current under excitation of Au localized surface plasmon resonance (LSPR). A turnover of 8.76 s(-1) at 300 mV overpotential is measured under LSPR excitation, which by far exceeds the activity of MoS2 catalysts reported recently. The HER enhancement can be largely attributed to the increase of carrier density in MoS2 induced by the injection of hot electrons of Au nanorods. We demonstrate that the synergistic effect of the hole scavengers can further facilitate electron-hole separation, resulting in a decrease of the overpotential of HER at MoS2 to ∼120 mV. This study highlights how metal LSPR activates the HER and promises novel opportunities for enhancing intrinsic activities of semiconducting materials.

Electrochromic materials are widely used in smart windows. An ideal future electrochromic window would be able to control visible light transmission, tune building's heat conversion of near-infrared (NIR) solar radiation, and reduce attacks by microorganisms. To date, most of the reports have primarily focused on visible-light transmission modulation using electrochromic materials. Herein, we report the fabrication of an electrochromic-photothermal film by integrating electrochromic WO with plasmonic Au nanostructures and demonstrate its adjustability during optical transmission and photothermal conversion of visible and NIR lights. The localized surface plasmon resonance (LSPR) of Au nanostructures and the broadband nonradiative plasmon decay are proposed to be tunable using both the electric field and the WO substrate. Further enhanced photothermal conversion is achieved in colored state, which is attributed to coupling of traditional visible-band optical switching with NIR-LSPR extinction. The resulted electrochromic-photothermal film can also effectively reduce the numbers of attacking microorganisms, thus promising for use as a sterile smart window for advanced applications.

The effective capture and release of circulating tumor cells (CTCs) is of significant importance in cancer prognose and treatment. Here we report a highly efficient method to capture and release human leukemic lymphoblasts (CCRF-CEM) using aptamers modified gold nanowire arrays (AuNWs). The gold nanowires, showing tunable morphologies from relatively random pillar deposit to relatively uniform arrays, were fabricated by electrochemical deposition using anodic aluminum oxide (AAO) as template. Upon simply being modified with aptamers by Au-S chemistry, the AuNWs exhibit higher specificity to target cells. Also compared to flat gold substrate, the AuNWs with nanostructure can capture target cells with much higher capture yield. Moreover, the captured CCRF-CEM cells can be released from AuNWs efficiently with little damage through an electrochemical desorption process. We predict that our strategy has great potential in providing a simple and economical platform for CTCs isolation, cancer diagnosis, and therapy.

energy storage (EES)-primarily supercapacitors and metal-ion batteries (MIBs, e.g., lithium-ion batteries (LIBs), sodiumion batteries (SIBs), and potassium-ion batteries (PIBs)).Both supercapacitors and batteries typically consist of current collectors, electrodes, electrolyte, and a separator. By applying a suitable potential between current collectors, the charge/discharge process takes place mediated by the electrode materials, and the electrolyte ions (i.e., the charge carriers) are accordingly driven to travel across the separator so as to connect the circuit. In recent years, solidstate electrolytes (SSEs) are also under popular development to enhance cell voltage (energy density) and safety of the devices. [1] Upon charging, electrical energy is converted to electrostatic potential for supercapacitors and to chemical energy for batteries, and vice versa. Therefore, each device has pros and cons. Supercapacitors usually provide a high power density (i.e., a fast charge/ discharge velocity) due to the fast physical charge-discharge process across the interfaces between electrode materials and the electrolyte solutions, while the energy density is usually small (≈5 Wh kg −1 ). In comparison, batteries often offer a large energy density (i.e., a large specific energy capacity of ≈200 Wh kg −1 ) attributed to the chemical redox reactions which take place throughout the whole volume of electrode materials, while the operation rate is relatively slow. [2] To construct desirable energy storage devices, porous materials have been widely adopted, particularly for electrodes and SSEs. These materials typically feature a large fraction of interconnected or reticulated porosity with a high specific surface area (SSA), offering numerous potential active sites and mass transfer channels. For example, porous materials based on nanocarbons (e.g., carbon nanotubes, graphene), conducting polymers, and conjugated microporous polymers with high electrical conductivity and large SSAs have been frequently adopted for supercapacitors, [3] while porous carbons, MoS 2 , and metal oxides have been used for LIBs because of the theoretically large stoichiometric lithium content in the respectively lithiated compound and an accelerated Li diffusion rate inside the pores. [4][5][6] Despite considerable progress made so far, these porous materials fall short of sufficiently large SSAs and readily tunable pores, which constrain the upper limit for the performance optimization and affect an accurate investigation of the structure-performance relationship.Metal-organic frameworks (MOFs) feature rich chemistry, ordered micro-/ mesoporous structure and uniformly distributed active sites, offering great scope for electrochemical energy storage (EES) applications. Given the particular importance of porosity for charge transport and catalysis, a critical assessment of its design, formation, and engineering is needed for the development and optimization of EES devices. Such efforts can be realized via the design of reticular chemistry, multiscale...

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Signal amplification in biological systems is achieved by cooperatively recruiting multiple copies of regulatory biomolecules. Nevertheless, the multiplexing capability of artificial fluorescent amplifiers is limited due to the size limit and lack of modularity. Here, we develop Cayley tree-like fractal DNA frameworks to topologically encode the fluorescence states for multiplexed detection of low-abundance targets. Taking advantage of the self-similar topology of Cayley tree, we use only 16 DNA strands to construct n-node (n = 53) structures of up to 5 megadalton. The high level of degeneracy allows encoding 36 colours with 7 nodes by site-specifically anchoring of distinct fluorophores onto a structure. The fractal topology minimises fluorescence crosstalk and allows quantitative decoding of quantized fluorescence states. We demonstrate a spectrum of rigid-yet-flexible super-multiplex structures for encoded fluorescence detection of single-molecule recognition events and multiplexed discrimination of living cells. Thus, the topological engineering approach enriches the toolbox for high-throughput cell imaging.

The macromolecular photosensitizer could bind and eliminate bacteria efficiently.

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