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Electrochemical reduction of CO 2 provides an opportunity to reach a carbon-neutral energy recycling regime, in which CO 2 emissions from fuel use are collected and converted back to fuels. The reduction of CO 2 to CO is the first step towards the synthesis of more complex carbon-based fuels and chemicals. Therefore, understanding this step is crucial for the development of high-performance electrocatalyst for CO 2 conversion to higher order products such as hydrocarbons. Here we synthesize atomic iron dispersed on nitrogen-doped graphene (Fe/NG) as an efficient electrocatalyst for CO 2 reduction to CO. Fe/NG has a low reduction overpotential with high Faradic efficiency up to 80%. The existence of nitrogenconfined atomic Fe moieties on the nitrogen-doped graphene layer was confirmed by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure analysis. The Fe/NG catalysts provide an ideal platform for comparative studies of the effect of the catalytic center on the electrocatalytic performance. The CO 2 reduction reaction mechanism on atomic Fe surrounded by four N atoms (Fe-N 4) embedded in nitrogen-doped graphene is further investigated through density functional theory calculations, revealing a possible promotional effect of nitrogen doping on graphene.

Nanoparticles have shown promise as both drug delivery vehicles and direct antitumor systems, but they must be properly designed in order to maximize efficacy. Computational modeling is often used both to design new nanoparticles and to better understand existing ones. Modeled processes include the release of drugs at the tumor site and the physical interaction between the nanoparticle and cancer cells. In this article, we provide an overview of three different targeted drug delivery methods (passive targeting, active targeting and physical targeting), compare methods of action, advantages, limitations, and the current stage of research. For the most commonly used nanoparticle carriers, fabrication methods are also reviewed. This is followed by a review of computational simulations and models on nanoparticle-based drug delivery.

The development of a rechargeable Li metal anode (LMA) is an important milestone for improved battery technology. Practical issues hindering LMAs are the formation of Li dendrites and inactive Li during plating and stripping processes, which can cause short circuits, thermal runaway, and low coulombic efficiency (CE). Here, the use of a laser‐induced silicon oxide (LI‐SiOx) layer derived from a commercial adhesive tape to improve the reversibility of Li metal batteries (LMBs) is studied. The silicone‐based adhesive of the tape is converted by a commercial infrared laser into a homogeneous porous SiOx layer deposited directly over the current collector. The coating results in superior performance by suppressing the formation of Li dendrites and inactive Li and presenting higher average CE of 99.3% (2.0 mAh cm−2 at 2.0 mA cm−2) compared to bare electrodes. The thickness and morphology of the deposited Li is investigated, revealing a different mechanism of Li deposition on coated electrodes. The laser coating affords a method that is fast and avoids the use of toxic organic solvents and extensive drying times. The improved performance with the SiOx coating is demonstrated in LMB with a zero‐excess (“anode‐free”) configuration where a 100% improved performance is verified.

Mitochondria, as essential and interesting organelles within the eukaryotic cells, play key roles in a variety of pathologies, and its abnormalities are closely associated with Alzheimer's disease (AD) and other diseases. Studies have shown that the abnormal of viscosity and concentration of hydrogen peroxide in mitochondria were all associated with AD. Accordingly, the detection of viscosity and hydrogen peroxide in mitochondria has attracted great attention. However, it remains a great challenge to explore a single probe, which can dual-detect the viscosity and HO in mitochondria. Herein, in two ways to prevent the twisted internal charge transfer (TICT) process, we designed and sythesized the first dual-detection fluorescent probe Mito-VH that can visualize viscosity and HO in mitochondria with different fluorescence signals in living cells.

NiFe-based catalysts are highly active for the oxygen evolution reaction (OER) in alkaline electrolytes. These catalysts are generally synthesized by solution-based methods. We present an in situ synthesis method for NiFe-based OER catalysts through a laserinduced graphene (LIG)-assisted process. By loading the metal precursor on a preformed LIG surface followed by laser scribing, we synthesized the NiFe/LIG catalysts via a solid phase transition that did not require utilization of CVD or typical solution-based reactions. The catalysts showed high OER activity and durability. The overpotential at 10 mA cm −2 is as low as 240 mV with a Tafel slope of 32.8 mV dec −1 in 1 M KOH. Additionally, this method worked well on a carbon fiber paper substrate, providing a convenient approach for the preparation of a free-standing catalytic electrode. This method provides a potential route to the facile synthesis of a variety of catalysts on a conductive surface.

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An efficient metal-free catalyst is presented for oxygen evolution and reduction based on oxidized laser-induced graphene (LIG-O). The oxidation of LIG by O plasma to form LIG-O boosts its performance in the oxygen evolution reaction (OER), exhibiting a low onset potential of 260 mV with a low Tafel slope of 49 mV dec , as well as an increased activity for the oxygen reduction reaction. Additionally, LIG-O shows unexpectedly high activity in catalyzing Li O decomposition in Li-O batteries. The overpotential upon charging is decreased from 1.01 V in LIG to 0.63 V in LIG-O. The oxygen-containing groups make essential contributions, not only by providing the active sites, but also by facilitating the adsorption of OER intermediates and lowering the activation energy.