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Mass-transport acceleration is essential toward enhanced electrocatalytic performance yet rarely recognized under irradiation, because light is usually reported to improve charge transfer. We studied laser-enhanced mass transport through the heterojunction between Ag and semiconductor Fe

Structure-guided microtuning of an

The interchangeable operation of alkaline oxygen evolution and reduction using bifunctional electrocatalysts in devices consolidates the commercialization milestone of energy storage in hydrogen, a...

Sulfamates and sulfamides are prevalent in biological molecules, but their universal synthetic methods are limited. We herein report a sulfamoylation agent with high solubility and shelf stability. Various sulfamates and sulfamides can be synthesized directly from alcohols or amines by employing this agent with high selectivity and high yields. This protocol was also successfully used for late-stage sulfamoylation of pharmaceuticals containing a hydroxyl or amino group.

Robust antimicrobial coatings featuring high transparency, strong bactericidal activity, and easy application procedure on generic surfaces can be widely accepted by the public to prevent pandemics. In this work, we demonstrated the hand sprayer-based approach to deposit complex oxide coatings composed of Co-Mn-Cu-Zn-Ag on screen protectors of smartphones through acidic redox-assisted deposition (ARD). The as-obtained coatings possess high transparency (99.74% transmittance at 550 nm) and long-lasting durability against swiping (for 135 days of average use) or wet cleaning (for 33 days of thrice-a-day routine). The spray coating enabling 3.14% E. coli viability can further be reduced to 0.21% through a consistent elemental composition achieved via the immersion method. The high intake of Cu2+ in the coating is majorly responsible for bactericidal activity, and the presence of Ag+ and Zn2+ is necessary to achieve almost complete eradication. The success of extending the bactericidal coatings on other typical hand-touched surfaces (e.g. stainless steel railings, rubber handrails, and plastic switches) in public areas has been demonstrated.

In this study, a metal–organic framework, namely, Zn3(BTC)2 (BTC = 1,3,5-benzenetricaboxylic acid), was solvothermally synthesized and employed as a catalyst for biodiesel production from degummed vegetable oil via a one-step transesterification and esterification reaction. The resulting Zn3(BTC)2 particles exhibit a well-defined triclinic structure with an average size of about 1.2 μm, high specific surface area of 1176 m2/g, and thermal stability up to 300 °C. The response surface methodology–Box–Behnken design (RSM–BBD) was employed to identify the optimal reaction conditions and to model the biodiesel yield in relation to three important parameters, namely, the methanol/oil molar ratio (4:1–8:1), temperature (45–65 °C), and time (1.5–4.5 h). Under the optimized reaction conditions (i.e., 6:1 methanol/oil molar ratio, 65 °C, 4.5 h), the maximum biodiesel yield reached 89.89% in a 1 wt % catalyst, which agreed very well with the quadratic polynomial model’s prediction (89.96%). The intrinsic catalytic activity of Zn3(BTC)2, expressed as the turnover frequency, was found to be superior to that of other MOF catalysts applied in the transesterification and esterification reactions. The reusability study showed that the as-synthesized Zn3(BTC)2 catalyst exhibited good stability upon three consecutive reuses without a noticeable decrease in the methyl ester yield (∼4%) and any appreciable metal leaching (

The search for high-active and long-lasting materials is of paramount significance for elimination of aqueous organic contaminants. Herein, a nitrogen-coordinated cobalt embedded in hollow carbon p...

Long-term efficient separation of highly emulsified oily wastewater is challenging. Reported herein is the preparation of a reinforced superhydrophilic, underwater superoleophobic membrane with demulsification properties using active iron nanoparticles in situ generated on a polydopamine (PDA)/polyethylenimine (PEI)-modified polyvinylidene fluoride (PVDF) membrane surface. A stable zwitterionic structure is fabricated on the membrane surface and provides it with an excellent capability of binding a hydration layer, leading to enhanced superhydrophilic/underwater superoleophobic properties. The interaction between the membrane surface and water is quantified using the relaxation time of water. After iron nanoparticles in situ anchoring, the superhydrophilic, underwater superoleophobic PDA/PEI modified PVDF membrane shows more stable flux behaviors, higher oil separation efficiency, demulsification, and excellent antioil-fouling properties for various anionic, nonionic, and cationic surfactant-stabilized oil-in-water emulsions in a crossflow filtration system. The reinforced hydration layer and the amphoteric charged demusification properties of the membrane play important roles in enhancing the membrane separation performance. The reinforced membrane also exhibits excellent cleaning and reusability performance in long-term operations. The outstanding separation performance, as well as the simple and cost-effective fabrication process of the membrane with various favorable properties, highlight its promise in practical emulsified oily water applications.

Galvanic replacement (GR) is a widely used method to obtain substrates with nanostructure morphologies. However, substantial challenges related to the uniformity of the deposited nanostructures, th...

Sodium hypochlorite (NaClO) solution is a typical cleaning agent for membrane fouling. However, it can damage membrane chemical structures and produce toxic disinfection byproducts, which in turn reduces the membrane performance. This study focuses on the fabrication of active membranes thereby overcoming the limitations of chemical cleaning. A hierarchical active poly(vinylidene fluoride) membrane with polydopamine/polyethyleneimine (PEI) co-supported iron nanoparticle (Fe NP) catalysts was successfully constructed and denoted as a Fe-HP-membrane. The Fe-HP-membrane exhibited excellent advanced oxidation activity with maximum flux recoveries (∼85% with bovine serum albumin [BSA] and ∼95% with humic acid [HA] solutions). After the static experiment of ∼30 days, the BSA proteins and HA successfully desorbed from the membrane surface. Especially, with a trace amount of hydrogen peroxide (H2O2) flowing over the surface of the Fe-HP-membrane, highly exposed active sites were observed. Membrane cleaning showed that the "outside-to-in" active surfaces generated considerable amounts of •OH radicals at the interface of BSA or HA and the fouled membrane. As a result, the unwanted foulants were successfully removed from the membrane interface, enabling multiple use of the Fe-HP-membrane. Therefore, backwashing with a small amount of H2O2 (0.33 wt %) covered ∼20% of the flux. In contrary, backwashing with NaClO (1 wt %) can only achieve a flux recovery of ∼10% after six consecutive BSA filtration cycles. The Fe-HP-membrane exhibited better HA foulant removal (a flux recovery of ∼51%) after backwashing with H2O2 than using NaClO (a flux recovery of ∼43%). Our findings demonstrate a new platform for water treatment and regeneration of fouled membranes.

Significant heat generation in modern high-speed electronic devices requires elevated thermal conductivity of electrically conductive adhesives (ECAs), but the gap between discrete filler materials...

In this study, the effect of the grain boundary density on the transport properties of the Re-substituted higher manganese silicide Mn30.4Re6Si63.6 has been investigated. The efficiency of electric...

Carbon nitride compounds (CN) complexed with the in-situ-produced Cu(II) on the surface of CuAlO2 substrate (CN-Cu(II)-CuAlO2) is prepared via a surface growth process for the first time and exhibits exceptionally high activity and efficiency for the degradation of the refractory pollutants in water through a Fenton-like process in a wide pH range. The reaction rate for bisphenol A removal is ∼25 times higher than that of the CuAlO2. According to the characterization, Cu(II) generation on the surface of CuAlO2 during the surface growth process results in the marked decrease of the surface oxygen vacancies and the formation of the C–O–Cu bridges between CN and Cu(II)-CuAlO2 in the catalyst. The electron paramagnetic resonance (EPR) analysis and density functional theory (DFT) calculations demonstrate that the dual reaction centers are produced around the Cu and C sites due to the cation−π interactions through the C–O–Cu bridges in CN-Cu(II)-CuAlO2. During the Fenton-like reactions, the electron-rich center...

Efficient cycling of Fe3+/Fe2+ is a key step for the Fenton reaction. In this exploration, from microalgae, we have prepared a novel Fe-N-graphene wrapped Al2O3/pentlandite composite which showed high Fenton catalytic ability through accelerating of Fe3+ reduction. The catalyst exhibits high activity, good reusability along with stability, and wide adaptation for the organics degradation under neutral pH. High TON and H2O2 utilization efficiency have also reached by this catalyst. Characterization results disclose a unique structure that the layered Fe-N-graphene structure tightly covers on Al2O3/pentlandite particles. Mechanistic evidence suggests that the accelerated Fe3+/Fe2+ redox cycle originates from the enhanced electron transfer by the synergistic effect of Fe, Ni and Al in the catalyst, and it causes the low H2O2 consumption and high •OH generation rate. Moreover, organic radicals formed in the Fenton process also participate in the Fe3+ reduction, and this process may be accelerated by the N dop...

Solidification and aqueous redispersion of fluorophores are characteristically challenging because of aggregation quenching and random shifts of emission. Carbon-based polymer dots (PDs) have recently shown photoluminescent (PL) performances superior to those of conventional dyes and inorganic quantum dots (QDs) but suffer from significant fluorescence (FL) quenching and irreversible aqueous dispersion after solidification, which limits their applications in practical biomedicine and optical devices. In this work, we have compared three strategies by utilizing layered double hydroxides (LDHs) to effectively solidify PDs as robust and redispersible composites with well-preserved high brightness against wide pH (pH = 4–12) and strong ionic strength conditions, more stable than the pristine PDs. The resulting PD–LDH nanocomposites also show in vitro/in vivo bioimaging ability with low cytotoxicity and improved photostability. In addition, these composites exhibit high thermal stability at 150 °C for at least...

Recent progress in the relationship between carbohydrate cross-reactive determinants (CCDs) and allergic response highlights the importance of carbohydrate moieties in the innate immune system. Previous research pointed out that the protein allergen in Ginkgo biloba seeds is glycosylated, and the oligosaccharides conjugated to these proteins might also contribute to the allergy. The aim of this study was to analyze carbohydrate moieties, especially N-linked glycans, of glycoproteins from Ginkgo seeds originating from different places for detailed structures, to enable further research on the role played by N-glycans in Ginkgo-caused allergy. Results of monosaccharide composition and immunoblotting assays indicated the existence of N-glycans. Detailed structural elucidation of the N-glycans was further carried out by means of hydrophilic interaction ultraperformance liquid chromatography (HILIC-UPLC) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). In total, 14 out of 16 structures detected by UPLC were confirmed by MALDI-TOF-MS and tandem mass spectrometry, among which complex-type N-glycans bearing Lewis A determinants and high-mannose-type N-glycans were identified from Ginkgo seeds for the first time. Precise quantification of N-glycans was performed by use of an external standard, and both the absolute amount of each N-glycan and the percentage of different types of N-glycan showed significant diversity among the samples without any pattern of geographic variation.

Mono- and binuclear Cu(II) complexes bearing an unsymmetrical bipyridine–pyrazole–amine ligand were synthesized and characterized using X-ray diffraction. The mononuclear complex could be converted to the corresponding binuclear complexes under basic conditions due to the lability of the pyrazolyl N–H. Both complexes proved to be effective catalysts for azide–alkyne cycloaddition to form triazoles, with the binuclear complex exhibiting higher catalytic activity than the corresponding mononuclear one. The binuclear complex was effective at catalyst loadings as low as 0.0125 mol %, making it one of the most active catalysts for this reaction to date. Therefore, this catalyst was applied in the synthesis of potentially biologically active molecules. At 0.1–0.3 mol % catalyst loading, three precursors of Sorafenib analogs were synthesized in excellent yields. A one-pot variant of the reaction, generating the azide in situ, could also be performed using the binuclear complex as the catalyst. The transition met...

The muscarinic M1 acetylcholine receptor is a key target for drugs aimed at treating cognitive dysfunction, including the memory impairment in Alzheimer’s disease. The overall question of the current study was to ask how systemic administration of the bitopic M1 agonist VU0364572, the M1 positive allosteric modulator BQCA, and the acetylcholinesterase inhibitor donepezil (current standard of care for Alzheimer’s disease), would impact spatial memory-related hippocampal function in rats. Hippocampal pyramidal neuron spiking and local field potentials were recorded from regions CA1 and CA3 as rats freely foraged in a recording enclosure. To assess the relative stability versus flexibility of the rats’ spatial representations, the walls of the recording enclosure were reshaped in 15-m intervals. As compared to the control condition, systemic administration of VU0364572 increased spatial correlations of CA1 and CA3 pyramidal neuron spiking across all enclosure shape comparisons, whereas BQCA and donepezil app...