Rapid Discrimination of Adsorbed Oxygen and Lattice Oxygen in Catalysts by the Cataluminescence Method

Adsorbed oxygen and lattice oxygen are crucial parameters for catalyst characterization and catalytic oxidation mechanism. Therefore, rapid discrimination of adsorbed oxygen and lattice oxygen is highly desired. Herein, a direct correlation between cataluminescence (CTL) kinetic curve and oxygen species was discovered. The adsorbed oxygen-catalyzed CTL only lasted for a few minutes, whereas the lattice oxygen-catalyzed CTL could exhibit hours of continuous luminescence. The long-term CTL was attributed to the slow migration of lattice oxygen in a slow and continuous catalytic oxidation reaction. In addition to the discrimination between the adsorbed oxygen and lattice oxygen by the CTL kinetic processes, the corresponding CTL intensity was positively proportional to their amounts. Accordingly, the developed catalytic oxidation-related CTL can be used as an indicator for rapid discrimination and determination of adsorbed oxygen and lattice oxygen in catalysts. Oxygen species detected by the proposed CTL method not only matched well with those obtained by conventional X-ray photoelectron spectroscopy and O2-temperature programmed methods but also offered some distinguished advantages, such as convenient operation, fast response, and low cost. It can be expected that the established oxygen-responsive CTL probe has great potential in distinguishing adsorbed oxygen and lattice oxygen in various catalysts

UV Blocking by Mg–Zn–Al Layered Double Hydroxides for the Protection of Asphalt Road Surfaces

Mg_aZn_bAl_c–CO₃ layered double hydroxides (LDHs) with varying magnesium/zinc ratios have been synthesized by a method involving separate nucleation and aging steps. The resulting LDHs were analyzed by powder X-ray diffraction, laser particle size analysis, scanning electron microscopy, and diffuse reflectance UV spectroscopy. The results show that the UV blocking properties of Mg_aZn_bAl_c–CO₃–LDHs depend on both the proportion of zinc and the particle size distribution. The UV absorbing properties of Mg_aZn_bAl_c–CO₃–LDHs increase with the content of zinc, which can be ascribed to the decrease in the band gap energy, as has been observed experimentally and confirmed by density functional theory calculations. The UV screening properties of Zn₄Al₂–CO₃–LDHs were found to increase with increasing particle size, which can be explained by Mie scattering theory. Moreover, in accelerated UV light irradiation aging tests, LDH-modified asphalt samples showed excellent resistance to UV aging, with the efficacy of the LDH increasing with increasing zinc content

Magnetically Double-Shelled Layered Double Oxide (LDO)/LDO/γ-Fe₂O₃ Composite for Highly Efficient Removal of Congo Red and Chromium(VI)

Novel double-shelled core-shell-type magnetic composites MgFexAl-LDO/LDO/γ-Fe2O3 (x = 0, 0.1, and 0.5) were synthesized by a cost-effective two-step coprecipitation method followed by proper calcination. The composites are constructed by two layers of LDO nanosheets (∼80 × 10 nm) which shows vertically oriented relay growth on the surface of spherical γ-Fe2O3. The thickness of LDO shells is ca. 220 ∼ 260 nm, providing a large number of effective adsorption sites and numerous open channels composed of adjacent LDO nanosheets. All the composites show excellent adsorption capacities for Congo Red (CR) and Cr­(VI). Especially, the MgAl-LDO/LDO/γ-Fe2O3 exhibits the maximum adsorption capacity (qmax = 123.4 mg g–1) for Cr­(VI), which is due to the double-shelled morphology with a large Brunauer–Emmett–Teller area (219 m2 g–1), the electrostatic attraction between the positive LDO shells and Cr­(VI) oxyanions, and the adsorption-coupled reduction, with the adsorbed Cr­(VI) anion reduced to Cr­(III) by hydroxyl groups of the hydrated metal ions and reconstructed into layer double hydroxide layers by the “memory effect”. The MgAl-LDO/LDO/γ-Fe2O3 and MgFe0.1Al-LDO/LDO/γ-Fe2O3 show extraordinary adsorption efficiency for CR with very close qmax values (3980 and 3832 mg g–1, respectively). The former can be attributed to its large SBET and strong LDO shellsCR anion electrostatic interaction, while the latter (99 m2 g–1) can still be ascribed to the complexing function of a small amount of Fe3+ species to CR. The MgAl-LDO/LDO/γ-Fe2O3 composite can be conveniently separated and recovered from the aqueous solution after adsorption by an external magnet. The fourth cycle efficiency of up to 84% implies a promising application prospect

Layered Dinitrostilbene-Based Molecular Solids with Tunable Micro/Nanostructures and the Reversible Fluorescent Response to Explosives

The ability to modulate and control the fluorescence properties of molecular solids at the micro/nanoscale is important to develop high-performance optoelectronic materials and sensors. Here we report the tunable one-photon and two-photon fluorescence as well as micro/nanostructures of dinitrostilbene-based (DNS) chromophore by the formation of layered multicomponent crystals with guanidinium cation (GD) through hydrogen-bonding assembly. The as-prepared GD₂DNS bulk crystal shows a red-shift emission as well as enhanced photoluminescence quantum yield and fluorescence lifetime compared with those of the Na₂DNS sample, which is related to the structural transfer of DNS from staggered arrangement to parallel fashion within the crystal. Periodic density functional theoretical calculations further show that the introduction of different cationic units can modify the frontier orbital distribution and electronic structure of DNS anions within the multicomponent crystals. Moreover, one-dimensional GD₂DNS nanobelts with well-aligned orientation can be further obtained by a combined ultrasound and coprecipitation method. The GD₂DNS nanobelts undergo a blue-shift fluorescence compared with its bulk crystal, and exhibit alternated photoresponse (such as emission wavelength and intensity) upon interaction with different nitroaromatic explosives (trinitrotoluene, picric acid and m-dinitrobenzen). Therefore, this work gives a facile bottom-up self-assembly rout to prepare organic multicomponent materials with tunable fluorescence properties and micro/nanostructures, which can be potentially used as luminescence detector for nitroaromatic explosives

Layered Dinitrostilbene-Based Molecular Solids with Tunable Micro/Nanostructures and the Reversible Fluorescent Response to Explosives

The ability to modulate and control the fluorescence properties of molecular solids at the micro/nanoscale is important to develop high-performance optoelectronic materials and sensors. Here we report the tunable one-photon and two-photon fluorescence as well as micro/nanostructures of dinitrostilbene-based (DNS) chromophore by the formation of layered multicomponent crystals with guanidinium cation (GD) through hydrogen-bonding assembly. The as-prepared GD₂DNS bulk crystal shows a red-shift emission as well as enhanced photoluminescence quantum yield and fluorescence lifetime compared with those of the Na₂DNS sample, which is related to the structural transfer of DNS from staggered arrangement to parallel fashion within the crystal. Periodic density functional theoretical calculations further show that the introduction of different cationic units can modify the frontier orbital distribution and electronic structure of DNS anions within the multicomponent crystals. Moreover, one-dimensional GD₂DNS nanobelts with well-aligned orientation can be further obtained by a combined ultrasound and coprecipitation method. The GD₂DNS nanobelts undergo a blue-shift fluorescence compared with its bulk crystal, and exhibit alternated photoresponse (such as emission wavelength and intensity) upon interaction with different nitroaromatic explosives (trinitrotoluene, picric acid and m-dinitrobenzen). Therefore, this work gives a facile bottom-up self-assembly rout to prepare organic multicomponent materials with tunable fluorescence properties and micro/nanostructures, which can be potentially used as luminescence detector for nitroaromatic explosives

Layered Dinitrostilbene-Based Molecular Solids with Tunable Micro/Nanostructures and the Reversible Fluorescent Response to Explosives

The ability to modulate and control the fluorescence properties of molecular solids at the micro/nanoscale is important to develop high-performance optoelectronic materials and sensors. Here we report the tunable one-photon and two-photon fluorescence as well as micro/nanostructures of dinitrostilbene-based (DNS) chromophore by the formation of layered multicomponent crystals with guanidinium cation (GD) through hydrogen-bonding assembly. The as-prepared GD₂DNS bulk crystal shows a red-shift emission as well as enhanced photoluminescence quantum yield and fluorescence lifetime compared with those of the Na₂DNS sample, which is related to the structural transfer of DNS from staggered arrangement to parallel fashion within the crystal. Periodic density functional theoretical calculations further show that the introduction of different cationic units can modify the frontier orbital distribution and electronic structure of DNS anions within the multicomponent crystals. Moreover, one-dimensional GD₂DNS nanobelts with well-aligned orientation can be further obtained by a combined ultrasound and coprecipitation method. The GD₂DNS nanobelts undergo a blue-shift fluorescence compared with its bulk crystal, and exhibit alternated photoresponse (such as emission wavelength and intensity) upon interaction with different nitroaromatic explosives (trinitrotoluene, picric acid and m-dinitrobenzen). Therefore, this work gives a facile bottom-up self-assembly rout to prepare organic multicomponent materials with tunable fluorescence properties and micro/nanostructures, which can be potentially used as luminescence detector for nitroaromatic explosives

Ag–O–Co Interface Modulation-Amplified Luminol Cathodic Electrogenerated Chemiluminescence

It remains a great challenge to develop effective strategies for improving the weak cathodic electrogenerated chemiluminescence (ECL) of the luminol-dissolved O2 system. Interface modulation between metal and supports is an attractive strategy to improve oxygen reduction reaction (ORR) activity. Therefore, the design of electrocatalysts via interface modulation would provide new opportunities for the ECL amplification involving reactive oxygen species (ROSs). Herein, we have fabricated an Ag single-atom catalyst with an oxygen-bridged interface (Ag–O–Co) through the electrodeposition of Ag on a CoAl layered double hydroxide (LDH) modified indium tin oxide (ITO) electrode (Ags/LDH/ITO). Interestingly, it was found that the cathodic ECL intensity of the luminol-dissolved O2 system at the Ags/LDH/ITO electrode was extraordinarily enhanced in comparison with those at bare ITO and other Ag nanoparticle-based electrodes. The enhanced ECL performances of the Ags/LDH/ITO electrode were attributed to the increasing amounts of ROSs by electrocatalytic ORR in the Ag–O–Co interface. The electron redistribution of Ag and Co bimetallic sites could accelerate electron transfer, promote the adsorption of O2, and sufficiently activate O2 through a four-electron reaction pathway. Finally, the luminol cathodic ECL intensity was greatly improved. Our findings can provide inspiration for revealing the interface effects between metal and supports, and open up a new avenue to improve the luminol cathodic ECL

Addressing the Origin of Single-Atom-Activated Supports Monitored by Electrochemiluminescence

Currently, much attention has been paid to the efforts to stabilize and regulate single atoms through supports to obtain decent electrocatalytic behaviors. However, little concern was given to the effect of single atoms on modulating the electronic structure of supports, despite the catalytic activities and large quantities of supports in the catalytic reactions. Herein, we have localized Ru single atoms onto two-dimensional layered double hydroxide (NiFe-LDH) and studied the role of Ru single atoms in adjusting the electronic structure of the NiFe-LDH support. Spin polarization of 3d electrons for Fe and electron redistribution in NiFe-LDH were effectively modulated through the interaction between Ru single atoms and NiFe-LDH. As a result, the luminol redox reaction and reactive oxygen revolution were simultaneously promoted by Ru single-atom-modulated NiFe-LDH, manifested as boosted electrochemiluminescence (ECL). Therefore, we have provided valid information to reveal the regulation effect of single atoms on the spin state and electronic structure of the supports. It is anticipated that our strategy may arouse wide interest in manipulating single-atom-modulated supports

Image_1_Global trends in research of pseudomyxoma peritonei: a bibliometric and visualization analysis.pdf

ObjectivePseudomyxoma peritonei (PMP) was a complex disease that had attracted increasing attention. However, there had been no bibliometric analysis of this disease so far. This study aimed to explore the current situation and frontier trend of PMP through bibliometric and visualization analysis, and to indicate new directions for future research.MethodsThe original research articles and reviews related to the PMP research were downloaded from Web of Science Core Collection on September 11, 2023. CiteSpace (6.2.R4) and VOSviewer(1.6.18) were used to perform bibliometric analysis of the publications, and establish the knowledge map. The data collected was analyzed using the Online Analysis Platform of Bibliometric to evaluate the cooperation of countries in this field.ResultsWe identified 1449 original articles and reviews on PMP published between 1998 and 2023. The number of publications on PMP increased continuously. The United States, the United Kingdom and China were the top contributors. The most productive organization was the MedStar Washington Hospital Center. Sugarbaker, Paul H. was the most prolific author and the most cited. Keyword analysis showed that “Pseudomyxoma peritonei”, “cancer”, “cytoreductive surgery”, and “hyperthermic intraperitoneal chemotherapy” were the most common keywords. The earliest and latest used keywords were “mucinous tumors” and “impact”, respectively. “classification”, “cytoreductive surgery”, “appendiceal” were the top 3 strongest citation bursts. The reference “Carr NJ, 2016, AM J SURG PATHOL” had the highest co-citations.ConclusionThis bibliometric analysis showed an increasing trend in literature related to PMP. The research trends and hotspots identified in this study could guide the future research directions in this field, in order to promote the development of PMP.</p