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Interface engineering is a simple and effective strategy for improving the photovoltaic performance and stability of perovskite solar cells (PSCs). Herein, an interface co-modification strategy is proposed, using [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and 2-fluoro-1,4-phenylenediammonium iodide (2FPPD) to modify the electron transport layer (ETL)/perovskite (PVK) and the PVK/hole transport layer (HTL) interfaces, respectively. A series of characterizations demonstrate that the PCBM&2FPPD interface co-modification strategy effectively enhances the extraction and transport efficiency of carriers at the interface, passivates surface defects, inhibits the nonradiative recombination of carriers, and simultaneously inhibits ion migration. Moreover, this strategy improves the crystallinity and surface hydrophobicity of PVK and optimizes the energy level alignment of PSCs. As a result, all photovoltaic parameters are improved after optimization, where the power conversion efficiency (PCE) of PSCs has increased from 17.01% to 18.36%. Meanwhile, the optimized PSCs show excellent environmental stability, which can be stably stored in air (RH = 10-20%) for about 800 h.

(Gd, Ni) codoped BiFeO3 (BGFNO) film exhibits robust ferroelectricity, which leads to excellent resistive switching behavior.

OBJECTIVE: The current total cavopulmonary connection Fontan has competing inflows and outflows, creating hemodynamic inefficiencies that contribute to Fontan failure and complicate placement and efficiency of mechanical circulatory support. We propose a novel convergent cavopulmonary connection (CCPC) Fontan design to create a single, converged venous outflow to the pulmonary arteries, thus increasing efficiency and mechanical circulatory support access. We then evaluate the feasibility and hemodynamic performance of the CCPC in various patient sizes using computational fluid dynamic assessments of computer-aided designs. METHODS: Cardiac magnetic resonance imaging data from 12 patients with single ventricle (10 total cavopulmonary connection, 2 Glenn) physiology (body surface area, 0.5-2.0 m(2)) were segmented to create 3-dimensional replicas of all thoracic structures. Surgically feasible CCPC shapes within constraints of anatomy were created using iterative computational fluid dynamic and clinician input. Designs varied based on superior and inferior vena cava conduit sizes, coronal attachment height, coronal entry angle, and axial entry angle of the superior vena cava to the inferior vena cava. CCPC designs were optimized based on efficiency (indexed power loss), risk of arteriovenous malformations (hepatic flow distribution), and risk of flow stasis (% nonphysiologic wall shear stress). RESULTS: All CCPC designs met hemodynamic performance thresholds for indexed power loss and hepatic flow distribution. CCPC designs showed improvements in reducing % nonphysiologic wall shear stress and balancing HFD. CONCLUSIONS: CCPC is physiologically and surgically feasible in various patient sizes using validated computational fluid dynamic models. CCPC configuration has analogous indexed power loss, hepatic flow distribution, and % nonphysiologic wall shear stress compared with total cavopulmonary connection, and the single inflow and outflow may ease mechanical circulatory support therapies. Further studies are required for design optimization and mechanical circulatory support institution.

Establish the quality control standard of rhubarb anti-trauma cataplasm. The qualitative analysis of rhubarb, angelica, and affective components of aloe-emodin, chrysophanol, and emodin has been done with thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), respectively. The TLC spots of rhubarb and angelica in rhubarb antisurgery papu were clear, and the negative control had no interference. HPLC results demonstrate that high intense hydrophilic compound peaks are observed on the lower side; however, low intense peaks are towards the higher side of the scale. The intensity of these peaks is decreased from mixed reference solution to test solution and negative reference solution.

Fouling and accretion have negative impacts on a plethora of processes. To mitigate heterogeneous nucleation of a foulant, lowering the surface energy and reducing surface roughness are desired. Here, we develop a multilayer coating to mitigate solution-based heterogeneous fouling for internal flows. The first layer is a sol-gel silicon dioxide (SiO2) coating, which acts as a corrosion barrier, creates the surface chemistry needed for covalent bonding of the slippery omniphobic covalently attached liquid (SOCAL), and ensures an atomically smooth (

While many algorithms have been proposed to estimate blood flow velocities based on the transport information of contrast agent acquired by digital subtraction angiography (DSA), most relevant studies focused on a single vessel, leaving a question open as to whether the algorithms would be suitable for estimating blood flow velocities in arterial systems with complex topological structures. In this study, a one-dimensional (1-D) modeling method was developed to simulate the transport of contrast agent in cerebral arterial networks with various anatomical variations or having occlusive disease, thereby generating an in silico database for examining the accuracies of some typical algorithms (i.e., time-of-center of gravity (TCG), shifted least-squares (SLS), and cross correlation (CC) algorithms) that estimate blood flow velocity based on the concentration-time curves (CTCs) of contrast agent. The results showed that the TCG algorithm had the best performance in estimating blood flow velocities in most cerebral arteries, with the accuracy being only mildly affected by anatomical variations of the cerebral arterial network. Nevertheless, the presence of a stenosis of moderate to high severity in the internal carotid artery could considerably impair the accuracy of the TCG algorithm in estimating blood flow velocities in some cerebral arteries where the transport of contrast agent was disturbed by strong collateral flows. In summary, the study suggests that the TCG algorithm may offer a promising means for estimating blood flow velocities based on CTCs of contrast agent monitored in cerebral arteries, provided that the shapes of CTCs are not highly distorted by collateral flows.

We report a generalized wet-chemical methodology for the synthesis of transition-metal (M)-doped brookite-phase TiO2 nanorods (NRs) with unprecedented wide-range tunability in dopant composition (M...

CO2 hydrogenation over ZrO2-supported NiFe catalysts is investigated to illustrate the role of Fe in controlling the activity and selectivity, and to reveal the structure-function relationship between metal-oxide interfaces and catalytic selectivities. The Ni-ZrO2 interfaces and Ni-FeOx interfaces are identified as the most likely active sites for the methanation reaction and the reverse water-gas shift reaction, respectively, using combined in-situ and ex-situ characterization techniques. The reaction mechanisms of CO2 hydrogenation to CH4 on the Ni-ZrO2 interfacial sites and to CO on the Ni-FeOx interfacial sites are further revealed by combined in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) calculations. Both experimental and theoretical results demonstrate that the binding energy of absorbed CO (*CO) is a key descriptor to predict CO2 hydrogenation selectivity: weak interaction (e.g., Ni-FeOx interfaces) promotes *CO desorption to increase CO selectivity, while moderate interaction (e.g., Ni-ZrO2 interfaces) facilitates further hydrogenation of *CO to produce CH4.

Catalytic reduction of CO2 by ethane creates an opportunity to use the shale gas and CO2 as the raw materials to produce syngas via dry reforming. In the present work, Pt-Ni bimetallic catalysts were investigated on reducible (CeO2, TiO2) and irreducible (γ-Al2O3, SiO2) oxides. The results showed that catalysts supported on reducible oxides, especially CeO2, were more active than those supported on irreducible oxides. Pulse and flow reactor studies and infrared spectroscopy experiments revealed a bi-functional Mars-Van Krevelen redox mechanism on PtNi/CeO2 and a mono-functional Langmuir-Hinshelwood mechanism on PtNi/SiO2, providing insights into the effects of reducibility of oxide supports on the reaction kinetics. Additionally, compared with the non-reducible SiO2, in situ X-ray diffraction (XRD) and pulse reactor analysis revealed that CO2 could be effectively activated on the reducible CeO2 and formed surface oxygen species to promote ethane dissociation into active carbon species. Thermogravimetric analysis (TGA), Transmission electron microscopy (TEM) and Raman spectroscopy showed that cokes formed on PtNi/CeO2 were primarily disordered/amorphous carbon species that could be easily removed during reforming.

Fe3O4 nanoparticles (NPs) with an average size of 8-10 nm have been successfully functionalized with various surface-treatment agents to serve as model systems for probing surface chemistry-dependent electrochemistry of the resulting electrodes. The surface-treatment agents used for the functionalization of Fe3O4 anode materials were systematically varied to include aromatic or aliphatic structures: 4-mercaptobenzoic acid, benzoic acid (BA), 3-mercaptopropionic acid, and propionic acid (PA). Both structural and electrochemical characterizations have been used to systematically correlate the electrode functionality with the corresponding surface chemistry. Surface treatment with ligands led to better Fe3O4 dispersion, especially with the aromatic ligands. Electrochemistry was impacted where the PA- and BA-treated Fe3O4 systems without the -SH group demonstrated a higher rate capability than their thiol-containing counterparts and the pristine Fe3O4. Specifically, the PA system delivered the highest capacity and cycling stability among all samples tested. Notably, the aromatic BA system outperformed the aliphatic PA counterpart during extended cycling under high current density, due to the improved charge transfer and ion transport kinetics as well as better dispersion of Fe3O4 NPs, induced by the conjugated system. Our surface engineering of the Fe3O4 electrode presented herein, highlights the importance of modifying the structure and chemistry of surface-treatment agents as a plausible means of enhancing the interfacial charge transfer within metal oxide composite electrodes without hampering the resulting tap density of the resulting electrode.

Sub-nanometer Rh clusters derived from Rh-doped SrTiO3, demonstrated by in-situ X-ray Diffraction (XRD) and X-ray Absorption Fine Structure (XAFS) measurements, are applied as highly active catalysts for CO2 reduction. Compared to the supported Rh/SrTiO3, the catalyst synthesized by a doping-segregation method exhibits a higher space-time yield (STY) to CO with a selectivity of 95% for CO2 reduction by hydrogen; it also shows a higher activity with a larger turnover frequency (TOF) for CO2 reduction by ethane. According to the in-situ diffuse reflectance infrared Fourier transformed spectroscopy (DRIFTS) experiments, the higher CO selectivity for CO2 hydrogenation is attributed to the lower CO binding strength resulted by the strong interactions (e.g., charge transfer) between Rh atoms and the oxide support with surface defects. The superior activity is suggested to be originated from the cooperative effect between the highly dispersed sub-nanometer Rh clusters for efficient dissociation of H2/C2H6 and the reconstructed SrTiO3 with oxygen vacancies for preferential adsorption/activation of CO2. The doping-segregation method provides a unique opportunity to tune the size of active metal clusters and the physicochemical properties of the oxide support, offering the potential for applications in a variety of chemical reactions.

Dry reforming of methane provides opportunities of using CH4 and CO2 to produce syngas. The PtCo/CeO2 bimetallic catalyst shows higher activity and H2/CO ratio than the corresponding monometallic catalysts, mainly attributed to the synergistic effect of Pt-Co. Structural feature of the PtCo/CeO2 catalyst was revealed by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of adsorbed CO and in situ techniques like X-ray diffraction (XRD), X-ray adsorption fine structure (XAFS) and ambient-pressure X-ray photoelectron spectroscopy (AP-XPS). Pt-Co alloy and separated Co particles co-existed in the bimetallic catalyst, whereas the former was determined as the dominant active structure with a Pt-Co-mixed-surface termination. During reaction, Pt and Co in the alloy structure nearly maintained their metallic state with slight oxygen decoration, yielding oxygen-metal site-pairs (O*-*). Combined kinetic investigations and DFT calculations reveal that the O*-modified catalytic surface of PtCo/CeO2 promotes C H bond activation with higher entropy contribution (less constraints) to compensate its higher activation barrier. Thermogravimetric analysis (TGA), transmission electron microscope (TEM) and Raman spectroscopy show that the PtCo/CeO2 catalyst is resistant to coke formation as effectively as Pt/CeO2 and can be easily regenerated by a mild CO2 treatment.

Objective Ellagic acid (EA) as a multi-target bioactive compound has been reported to improve diabetes-related complications, including diabetic nephropathy (DN). Herein, we plan to investigate the molecular mechanism underlying EA-mediated renal protection in diabetic mice. Methods Streptozotocin (STZ; 35 mg/kg successive injection for 5 times) was applied to establish DN model in mice. Normal or diabetic mice were administrated by EA (100 mg/kg/day) by intragastric administration for 8 weeks. In vitro diabetic cell model, podocytes and renal tubular epithelial cells (RTECs) were exposed to normal glucose (NG; 5 mM) or high glucose (HG; 30 mM). Results Our results demonstrated that EA treatment prevented HG-induced podocyte and RTEC apoptosis and growth inhibition by inhibiting NF-κB/miR-150-3p to activate BCL2 in vitro. In vivo diabetic model of mice, EA administration improved renal filtration function, tubular and glomerular injury, and interstitial fibrosis. More importantly, supplementation of EA also suppressed NF-κB/miR-150-3p activation and accelerated BCL2 expression in the kidney of diabetic mice. In another experiment, miR-150-3p antagomir as a potential gene therapeutic choice has been validated to rescue hyperglycemia-induced renal dysfunction in mouse model. Taken together, in vitro and in vivo experimental measurements corroborate that EA modulates NF-κB/miR-150-3p/BCL2 cascade signaling to attenuate renal damage in diabetic models. Conclusion Our findings revealed that EA modulated the suppression of NF-κB/miR-150-3p to activate BCL2 that contributed to prevent hyperglycemia-induced renal dysfunction. In addition, synthetic miR-150-3p antagomir or inhibitors could alleviate tubular injury and interstitial fibrosis, and prevent HG-induced podocyte and RTEC apoptosis.

This paper takes 2010-2018 Shanghai and Shenzhen A-share state-owned listed companies as a sample, from the perspective of internal governance and external environment, respectively, to study the influencing factors of the company’s innovation capability by means of the fixed-effect model. We find that in state-owned enterprises, there is an inverted U-shaped relationship between product market competition and enterprise innovation capabilities and the diversified ownership structure can significantly promote the improvement of corporate innovation capabilities. Further research indicates that the diversified ownership structure has a positive moderating effect on the relationship between product market competition and corporate innovation.

A novel CeO

Nanofiltration with high stable permeance is of great significance for wastewater treatment. Herein, we reported the novel polyamide thin-film composite (PA TFC) nanofiltration membranes prepared for the first time by blending nanometer cerium doped high silica ZSM-5 zeolites (CeO2@HSZSM-5, CHZ) in the aqueous phase followed by the classic interfacial polycondensation. The structural morphology of these membranes and their performance had been characterized. SEM and XPS characterizations clearly revealed the presence of inorganic CHZ in the PA layer. The results also showed that the CHZ-integrated inorganic-organic PA TFC membranes with a higher fraction of CHZ had a thinner PA active layer (28.3 ± 3.6 nm) and slightly enlarged pore size with lower crosslinking degree. The optimized membranes exhibited 1.65-folds pure water permeability of the traditional membrane, 20.3 L/(m2.h.bar) with comparable Na2SO4 and MgSO4 rejection of 95.8% and 91.1%, respectively. The rejection of dyes stayed stable above 96.0% with boosted permeance, and the membrane almost completely removed CR and RB as well as natural organic matters. The composite membrane also sustained superior stability and excellent antifouling performance. The as-prepared CHZ-integrated PA TFC membranes with regulatable structural morphology and superior separation properties enables the potential practical application in wastewater treatment.

Ethylene (C2H4) is one of the most important raw materials for chemical industry. The tandem reactions of CO2-assisted dehydrogenation of ethane (C2H6) to ethylene creates an opportunity to effectively use the underutilized ethane from shale gas while mitigating anthropogenic CO2 emissions. Here we identify the most likely active sites over CeO2-supported NiFe catalysts by using combined in situ characterization with density-functional theory (DFT) calculations. The experimental and theoretical results reveal that the Ni–FeOx interfacial sites can selectively break the C–H bonds and preserve the C–C bond of C2H6 to produce ethylene, while the Ni–CeOx interfacial sites efficiently cleave all of the C–H and C–C bonds to produce synthesis gas. Controlled synthesis of the two distinct active sites enables rational enhancement of the ethylene selectivity for the CO2-assisted dehydrogenation of ethane.

The surface properties that determine the selectivity of Mo2C catalysts in ethane oxidative dehydrogenation with CO2 as a soft oxidant were investigated using a combination of pulse experiments and in-situ spectroscopic methods. Oxygen modification was discovered to be crucial for inhibiting the cleavage of the C–C bond in ethane and enhancing the production of ethylene. The addition of the Fe promoter accelerated the formation of surface oxygen species and stabilized them from reduction by ethane, leading to a shorter induction period, higher ethylene yield, and improved stability.

Emerging applications require batteries to have both high energy and high power which are not necessarily compatible. The typical inverse relationship between power and energy in batteries is often due to the slow ion diffusion in electrode materials. While the optimization of current battery technology may be sufficient to fully address this issue, we present here that novel chemistry-focused strategies based on new fundamental understanding of materials may be applied to lead to the development of a new generation of batteries that store energy sufficiently and deliver it rapidly.

The oxygen evolution reaction (OER) has broad applications in electrochemical devices, but it often requires expensive and scarce Ir-based catalysts in acid electrolyte. Presented here is a framework to reduce Ir loading by combining core–shell iridium/metal nitride morphologies using in situ experiments and density functional theory (DFT) calculations. Several group VIII transition metal (Fe, Co, and Ni) nitrides are studied as core materials, with Ir/Fe4N core–shell particles showing enhancement in both OER activity and stability. In situ X-ray absorption fine structure measurements are used to determine the structure and stability of the core–shell catalysts under OER conditions. DFT calculations are used to demonstrate adsorbate binding energies as descriptors of the observed activity trends.

Carrier transport in semiconductor photoelectrodes strongly correlates with intrinsic material characteristics including carrier mobility and diffusion length, and extrinsic structural imperfections including mobile charged defects at domain boundaries, which collectively determines the photoelectrochemistry (PEC) performance. Here we elucidate the interplay between intrinsic carrier transport, domain-boundary-induced conductivity, and PEC water oxidation in the model photoanode of bismuth vanadate (BiVO4). In particular, epitaxial single-domain BiVO4 and c-axis-oriented multidomain BiVO4 thin films are fabricated using pulsed laser deposition to decouple the intrinsic and extrinsic carrier transport. In addition to the low intrinsic conductivity that is due to the small-polaron transport within BiVO4 domains, we identify anomalously high electrical conductivity arising from vertical domain boundaries for multidomain BiVO4 films. Local domain-boundary conduction compensates the inherently poor electron tr...

The size and morphology of metal nanoparticles (NPs) often play a critical role in defining the catalytic performance of supported metal nanocatalysts. However, common synthetic methods struggle to produce metal NPs of appropriate size and morphological control. Thus, facile synthetic methods that offer controlled catalytic functions are highly desired. Here we have identified a new pathway to synthesize supported Rh nanocatalysts with finely tuned spatial dimensions and controlled morphology using a doping-segregation method. We have analyzed their structure evolutions during both the segregation process and catalytic reaction using a variety of in situ spectroscopic and microscopic techniques. A correlation between the catalytic functional sites and activity in CO2 hydrogenation over supported Rh nanocatalysts is then established. This study demonstrates a facile strategy to design and synthesize nanocatalysts with desired catalytic functions.

A LaFe0.9Ni0.1O3 perovskite catalyst was evaluated for dry reforming of ethane (DRE), with two conventional oxide supported Ni catalysts (Ni/La2O3 and NiFe/La2O3) being used as references. LaFe0.9Ni0.1O3 showed the best activity and high coke-/sintering-resistance. TEM, TGA, and Raman characterizations confirmed that the deactivation of Ni/La2O3 was owing to the growth of Ni particles and the accumulation of coke, although the formation of La2O2CO3 was able to remove part of the coke during the reaction. The introduction of Fe-related species inhibited the coke formation while decreased the activity due to the loss of active sites. A portion of Ni ions in the perovskite lattice could be reduced to form highly dispersed and stable Ni nanoparticles on the surface during the reaction and oxygen vacancies were left in the perovskite lattice. Pulse reactor studies revealed that the oxygen vacancies in the perovskite could facilitate the activation and dissociation of CO2 to form CO and reactive oxygen species. Moreover, C2H6 was activated with the assistance of oxygen from the surface or subsurface of LaFe0.9Ni0.1O3 to form CO, rather than directly dissociated to surface carbon species as observed over Ni/La2O3.

A feathery-shaped form of BiOCl (BOC-M) with a high concentration of oxygen vacancies was successfully synthesized using the ultrasound method at room temperature with maltitol as a surfactant. BOC-M was found to exhibit excellent visible-light photocatalytic activities for the degradations of the antibiotic tetracycline hydrochloride (TC-HCl) and rhodamine B (RhB), whose reaction rate was found to be approximately 3 times higher than that using bulk BiOCl (BOC). The enhanced visible photocatalytic performance of BOC-M was ascribed to its high concentration of oxygen vacancies, large specific surface area and strong hydrophilicity. Moreover, the photocatalytic reaction mechanism was further revealed by performing radical- and hole-trapping experiments and electron spin resonance spectroscopy (ESR). The results suggested that ˙O2− was the main active species during the degradation process. This work provided a facile and scalable method to synthesize maltitol-assisted Bi-based photocatalysts and shed light on the highly efficient catalysis offered by BiOCl resulting from the oxygen vacancies produced by the new synthetic route we developed.

Ultra-small gold nanoclusters were synthesized via a ligand exchange method and deposited onto different TiO2 supports to study their properties. STM imaging revealed that the as-synthesized gold nanoclusters had 2-D morphology consisting of monolayers of gold atoms. Subsequent XPS, XAFS, and CO oxidation TPD results indicated that heat treatments of gold clusters at different temperatures significantly altered their electronic and catalytic properties due to ligand deprotection and cluster agglomeration.

The selectivity of CO2 hydrogenation can be significantly tuned by controlling the valence state of nickel using lanthanum-iron-nickel perovskites. Nickel with higher valence states weakens the binding of CO and increases the activation barrier for further CO hydrogenation, leading to a higher CO selectivity than the metallic nickel.

Optical and photocatalytic properties were determined for the solid solution series (GaN)1–x(ZnO)x synthesized at high pressure over the entire compositional range (x = 0.07 to 0.9). We report for the first time photocatalytic H2 evolution activity from water for (GaN)1–x(ZnO)x without cocatalysts, pH modifiers and sacrificial reagents. Syntheses were carried out by reacting GaN and ZnO in appropriate amounts at temperatures ranging from 1150 to 1200 °C, and at a pressure of 1 GPa. ZnGa2O4 was observed as a second phase, with the amount decreasing from 12.8 wt% at x = 0.07 to ∼0.5 wt% at x = 0.9. The smallest band gap of 2.65 eV and the largest average photocatalytic H2 evolution rate of 2.31 μmol h−1 were observed at x = 0.51. Samples with x = 0.07, 0.24 and 0.76 have band gaps of 2.89 eV, 2.78 eV and 2.83 eV, and average hydrogen evolution rates of 1.8 μmol h−1, 0.55 μmol h−1 and 0.48 μmol h−1, respectively. The sample with x = 0.9 has a band gap of 2.82 eV, but did not evolve hydrogen. An extended photocatalytic test showed considerable reduction of activity over 20 hours.

Ultra-thin loose thin-film composite (TFC) nanofiltration membrane with potential high permeability is an urgent need in water purification. However, its tailor-made structure and morphology remains a challenge. Herein, a novel composite membrane was proposed for the first time by introducing 3,5-diamino-1,2,4 triazole (GAZ) and piperazine with trimesoyl chloride (TMC) into polyamide layer. The physic-chemical properties of the membranes prepared with various GAZ concentrations in the aqueous phase were characterized. GAZ-incorporated membranes had a thinner active layer and larger pore sizes as well as smoother surface morphology with increasing GAZ content. The presence of GAZ made the pure water permeance of the membranes 2.3-folds of the typical TFC membrane without GAZ, up to 30.5 LMH/bar with a comparable Na2SO4 rejection of 93.5%. The membranes fabricated with a higher GAZ fraction exhibited superior removal for the dyes of Rose bengal (>99.6%) and Congo red (>97.5%) with the dye permeance over 23.0 LMH/bar, and higher rejection rates for natural organic matters (>98.5%, >98.0% and >93.0% for sodium alginate, bovine serum albumin and humic acid, respectively). The membranes with stable operation implied their potential applications in water desalination and purification.

Conversion of methanol and dimethyl ether (DME) to high-octane gasoline catalyzed by beta zeolite (BEA) provides an opportunity for the production of high-quality fuels from renewable carbon sources (e.g., gasified biomass). Recent research demonstrated that a Cu-modified BEA zeolite catalyst (Cu/BEA) offered advantages over the unmodified BEA catalyst due to multifunctional Cu species that enabled incorporation of co-fed H2, reactivation of light alkanes, and reduction of products from the aromatic hydrocarbon pool. The shift in hydrocarbon pool chemistry has the potential to influence the identity and relative composition of surface carbon species that are often linked to deactivation. A detailed understanding of these carbon species is important to develop an effective and efficient regeneration procedure that can enable the transition from fundamental catalyst development to commercial application. Here, we applied complementary ex situ and in situ characterization techniques to compare the structures of surface carbon species on post-reaction Cu/BEA and unmodified BEA catalysts. Both catalysts contained acyclic and aromatic hydrocarbons along with graphitic carbon species. However, the post-reaction Cu/BEA catalyst had a lower polycyclic aromatic content, and further, the graphitic species were more hydrogenated and defective. It was also found that the presence of Cu promoted carbon removal at lower temperatures than for unmodified BEA through activation of O2 by Cu oxide during thermal oxidation. The fundamental insight into the composition of surface carbon species enabled the design of an effective and efficient regeneration strategy for the DME homologation reaction over Cu/BEA, resulting in full recovery of the catalyst activity.

A novel CeO2 doped high silica ZSM-5(CeO2@HSZSM-5) composite was originally fabricated via ammonia precipitation for the catalytic ozonation of sulfamethoxazole (SMX). Physicochemical properties have been investigated through electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy, etc. The prepared nanometer CeO2@HSZSM-5 had a much higher specific surface (348–395 m2/g), a finer crystallite size (8.2–33.5 nm) and superior stability. Temperature-programmed desorption and reduction analysis revealed that the formed CeO2 nanoparticles on the surface of CeO2@HSZSM-5 could improve the reducibility of surface-capping oxygen, induce more oxygen vacancies and promote oxygen migration. CeO2@HSZSM-5 exhibited excellent catalytic performance for SMX mineralization in the pH range of environmental waters. The great enhancement of CeO2@HSZSM-5 catalytic activity was ascribed to the conversion of O3 into active oxygen involved in SMX mineralization, including .OH, O2.– and 1O2. This work provides a reference for the removal of pollutants by zeolite supported Ce catalytic ozonation process in water.

In this work we describe a multimodal exploration of the atomic structure and chemical state of silica-supported palladium nanocluster catalysts during the hydrogenation of ethylene in operando conditions that variously transform the metallic phases between hydride and carbide speciations. The work exploits a microreactor that allows combined multiprobe investigations by high-resolution transmission electron microscopy (HR-TEM), X-ray absorption fine structure (XAFS), and microbeam IR (μ-IR) analyses on the catalyst under operando conditions. The work specifically explores the reaction processes that mediate the interconversion of hydride and carbide phases of the Pd clusters in consequence to changes made in the composition of the gas-phase reactant feeds, their stability against coarsening, the reversibility of structural/compositional transformations, and the role that oligomeric/waxy byproducts (here forming under hydrogen-limited reactant compositions) might play in modifying activity. The results pr...

An investigation of the adsorptive property of hydrated cement particle system for sulfur dioxide (SO2) removal was conducted. In situ and ex situ experiments using Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and X-ray Absorption Near Edge Spectroscopy (XANES) characterization techniques were employed to identify surface species formed during the exposure to SO2. Oxidation of SO2 to sulfate and sulfite species observed during these experiments indicated dominant reaction pathways for SO2 reaction with concrete constituents, such as calcium hydroxide, which were also moderated by adsorption on porous surfaces of crushed aggregates. The impact of variable composition of concrete on its adsorption capacity and reaction mechanisms was also proposed in this work.