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Lanthanide neodymium (Nd)‐based nanocrystals exhibit exceptional near‐infrared II (NIR‐II) fluorescence imaging properties, like narrow and multi‐peak emissions, long luminescence lifetime, and good photostability. However, long‐term accumulation in the reticuloendothelial system restrains their clinical applications due to toxicity in vivo. Here, a biodegradable hollow virus‐like neodymium oxide (Nd2O3) Nd‐nanoprobe is presented that is modified with cyclic arginine‐glycine‐aspartic acid (cRGD) pentapeptide, showing remarkable cancer‐targeting ability and NIR‐II fluorescence imaging features. The nanoprobe is biodegraded to 4–6 nm Nd2O3 nanogranules in vivo, and the pharmacokinetics of the nanoprobe demonstrated its rapid urine excretion and negligible systematic toxicity. Moreover, this nanoprobe can accurately identify malignant lesions from normal tissues in xenograft and transgenic mice models and precisely navigate breast cancer surgery under NIR‐II imaging guidance. Taken together, this Nd2O3‐based nanoprobe enables real‐time, dynamic delineation and accurate resection of cancers guided by NIR‐II fluorescence imaging with great potential for future clinical translation during breast‐conservative surgery. [ABSTRACT FROM AUTHOR]

The nickel particle size, distribution and interaction with support are crucial to the catalytic performance in dry reforming of methane reaction (DRM). Despite numerous literatures on dry reforming catalysis, the effect of solution pH on the catalytic performance is not well studied. Herein, we designed a series of Ni/SiO2 catalysts with different Ni particle sizes. The Ni particle size was controlled with altering the pH of the Ni nitrate solution via the addition of HNO3 or NH4OH. X‐ray diffraction (XRD) revealed that NH4OH promoted Ni/SiO2 catalysts present smaller NiO nanoparticles, and enhanced metal‐support interaction was evidenced from X‐ray photoelectron spectra (XPS) and H2 temperature‐programmed reduction (H2‐TPR) analyses. In addition, according to thermogravimetric analysis and differential scanning calorimetry (TG‐DSC) and transmission electron microscopy (TEM) results, the spent catalysts produced less carbon deposition and maintained Ni nanoparticles in smaller size after DRM reaction. Catalysts with nearly uniform and small particle size demonstrated a satisfying resistance to aggregation and carbon deposition, while realizing a high CH4, CO2 and Ctotal conversion (74.5, 83.7 and 79.7%, respectively). The present study provides a simple but effective way to change the metal‐support interaction and metal particle size. [ABSTRACT FROM AUTHOR]

Methanol is an essential chemical raw material and potential alternative energy source. In this paper, Cu based catalyst was prepared by the noble solid phase grinding method for CO2 hydrogenation to methanol. The influence of chelating agent, heating rate, calcination temperature and calcination period of the precursor on catalyst performance were studied in depth. The catalyst precursor with formic acid as a chelating agent was reduced in‐situ when calcined in nitrogen (N2) at 573 K. The formic acid was decomposed, releasing the reducing agents, CO and H2, resulting in continuous in‐situ CuO reduction to metallic Cu0. XRD, XPS, BET, TG‐DSC, H2‐TPR and other characterization techniques were employed to analyze the catalyst properties. Results revealed that CuO was successfully reduced in‐situ to Cu0 during calcination process in a nitrogen atmosphere without further reduction. The catalyst prepared by formic acid grinding (F/I−Cu/ZnO) showed highest catalytic activity compared with the conventional catalyst which was further reduced by 5% H2 (F/H−Cu/ZnO). CO2 conversion and methanol selectivity reached 33.44% and 84.26%respectively. [ABSTRACT FROM AUTHOR]

Zeolite synthesis involved use of large volumes of solvent that resulted in waste and enhanced production costs. In our study, we selected a solvent‐free synthesis route that involved mixing, grinding and crystallization at various times creating Fe@Silicalite‐1. This synthesis method produced a hierarchical in‐situ microporous crystal morphology with Fe particles caged inside zeolite displaying a high gasoline (C5‐C11) selectivity of 66.0% with a relatively low CO2 and CH4 selectivity (18.5% and 10.0%, respectively) in Fischer‐Tropsch synthesis. Prolonged crystallization time of 72 h and other subsequent procedures contributed to zeolite structure and performance. Iron moieties were appropriately immobilized over silicalite support. The characterization results were correlated with the zeolite activity and selectivity. This novel zeolite at its best possesses all the potential to be advanced in other related material synthesis because of its expedient procedure, characteristics and worthwhile outcomes. As a result of solvent‐free synthesis route, this Fe@Silicalite‐1 zeolite containing hierarchical in‐situ microporous crystal structure in union with Fe particles entrapped within zeolite contributed largely to gasoline product distribution of Fischer‐Tropsch synthesis reaction. The remarkable high gasoline selectivity of 66.0% has been achieved by this zeolite as a result of its intrinsic properties. [ABSTRACT FROM AUTHOR]

Heteroatom doping is a promising approach to improve the properties of carbon materials for customized applications. Herein, a series of Cu catalysts supported on boron-doped carbon nanotubes (Cu/ xB-CNTs) were prepared for the hydrogenation of dimethyl oxalate (DMO) to ethanol. The structure and chemical properties of boron-doped catalysts were characterized by XRD, TEM, N2O pulse adsorption, CO chemisorption, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption, which revealed that doping boron into CNT supports improved the Cu dispersion, strengthened the interaction of Cu species with the CNT support, introduced more surface acid sites, and increased the surface area of Cu0 and especially Cu+ sites. Consequently, the catalytic activity and stability of the catalysts were greatly enhanced by boron doping. 100 % DMO conversion and 78.1 % ethanol selectivity could be achieved over the Cu/1B-CNTs catalyst, the ethanol selectivity of which was almost 1.7 times higher than that of the catalyst without boron doping. These results suggest that doping CNTs with boron is an efficient approach to improve the catalytic performance of CNT-based catalysts for hydrogenation of DMO. The boron-doped CNT-based catalyst with improved ethanol selectivity and catalytic stability will be helpful in the development of efficient Cu catalysts supported on non-silica materials for selective hydrogenation of DMO to ethanol. [ABSTRACT FROM AUTHOR]

Water-soluble Zn xCd1− xSe quantum dots (QDs) with different amounts of Cd dopant are synthesized with 3-mercaptopropionic acid as a modifier under ambient conditions. Hydrazine hydrate is used as the surface stabilizer and pH adjuster during preparation. The effect of dopant amount, initial pH values, and heating time on the fluorescence properties are systematically studied. Based on the emission wavelength shift of Zn xCd1− xSe QDs from 430 to 578 nm, the colors of these QDs are adjustable from blue to orange. This adjustment is beneficial for developing sweat fingerprints on scotch tape. Fresh blood fingerprints on foil, ceramic tile, black plastic, scotch tape, and old bloody fingerprints on black ceramic tile are developed by the QDs. The results show that Zn0.77Cd0.23Se QDs (calculated composition; measured composition: Zn0.83Cd0.17Se) are the most effective material for developing blood fingerprints and is even superior to the traditional tetramethylbenzidine reagent. [ABSTRACT FROM AUTHOR]

The CO2 dry reforming of methane (DRM) reaction is an important technology with high prospects to reduce greenhouse gas emissions while simultaneously producing syngas for industrial usage. To date, the lack of an effective catalyst for the reaction has inhibited its commercialization. The coking and sintering behaviors of the catalysts are key factors for commercial production of syngas from DRM reaction. A microcapsule catalyst prepared by sol–gel method with Ni/ZSM‐5 as core and amorphous SiO2 as shell is successfully synthesized. The characterizations of the catalysts are analyzed using X‐ray powder diffraction (XRD), transmission electron microscopy (TEM), H2 temperature programmed reduction (H2‐TPR), NH3 temperature programmed desorption (NH3‐TPD), and thermogravimetry & differential scanning calorimetry (TGA‐DSC). The spatial confinement of the Ni metal particles between the SiO2 shell and ZSM‐5 suppresses Ni particles aggregation by strengthening the interaction between Ni particles and ZSM‐5 core. The coking‐resistant ability is equally improved. The capsule catalysts isolate the contact between the carbon deposits and the nickel active centre, thus improving the activity of the catalysts. 10Ni/ZSM‐5@SiO2 emerged superior in activity in comparison to other catalysts. [ABSTRACT FROM AUTHOR]