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The antimicrobial properties of copper are well-known but maintaining a low oxidation state of Cu in particles is difficult. Herein, antimicrobial CuxP particles were synthesized through phosphorization of Cu(OH)2, to lock copper in its monovalent state (as Cu3P). We found that the phosphorization could be achieved at temperatures as low as 200°C, with stable surface presence of Cu(I) on the resulting CuxP particles. Cu(I) can act as a one-electron reducing agent for molecular oxygen, to generate the highly reactive hydroxyl radical. In this study, CuxP displayed antibacterial activities on the Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli, with minimum inhibitory concentrations of 32 mg/L for the highest temperature particles (350°C) on both model bacteria. The evident membrane damage is consistent with the intended hydroxyl radical bacterial targeting mechanism. Low-temperature CuxP, although exhibiting lower antibacterial efficacies than those of the higher temperature variant, still showed competitive growth inhibiting activities when compared to other reported antimicrobial copper-based particles. The present work showcases advancements in particle technology that can lead to the development of a more robust antimicrobial agent, presenting a potent additive for self-disinfection applications.

This study investigated the use of ozone in a rotating packed bed (RPB) with liquid detention for the treatment of Basic Red 46 (BR-46). Liquid detention means that liquid accumulates at the lower section to a certain level in the RPB, which leads to longer liquid residence time and greater liquid holdup in the packing and cavity in the RPB. The experimental results showed that the presence of liquid detention in the RPB significantly enhanced the BR-46 treatment effect and ozone absorption rate. With 200 mL of liquid detention in the RPB, the decolorization rate, COD degradation rate, and ozone absorption rate were 34.7%, 62.8%, and 80.0% higher than those without liquid detention. The effects of the rotational speed of the RPB, ozone concentration, initial BR-46 concentration, liquid and gas flow rates on BR-46 degradation were also investigated, and it was found that the high-gravity environment is beneficial to the degradation of BR-46. These results suggest that with the utilization of the liquid detention phenomena in the high-gravity devices, the applications of the high-gravity technology can be extended to the processes where a long liquid residence time is required.

Electronic engineering of gallium nitride (GaN) is critical for enhancement of its electrode performance. In this work, copper (Cu) cation substituted GaN (Cu-GaN) nanowires were fabricated to understand the electronically engineered electrochemical performance for Li ion storage. Cu cation substitution was revealed at atomic level by combination of X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS), density functional theory (DFT) simulation, and so forth. The Cu-GaN electrode delivered high capacity of 813.2 mA h g−1 at 0.1 A g−1 after 200 cycles, increased by 66% relative to the unsubstituted GaN electrode. After 2000 cycles at 10 A g−1, the reversible capacity was still maintained at 326.7 mA h g−1. The DFT calculations revealed that Cu substitution introduced the impurity electronic states and efficient interatomic electron migration, which can enhance the charge transfer efficiency and reduce the Li ion adsorption energy on the Cu-GaN electrode. The ex-situ SEM, TEM, HRTEM, and SAED analyses demonstrated the reversible intercalation Li ion storage mechanism and good structural stability. The concept of atomic-arrangement-assisted electronic engineering strategy is anticipated to open up opportunities for advanced energy storage applications.

A novel oxygen reduction reaction (ORR) electrode comprising isolated Co atom decorated vertically aligned graphene nanosheets is designed, which can enable the most energy-efficient, rapid acidic H2O2 production in a flow-cell reactor.

Phenol is a nocuous water pollutant that threatens human health and the ecological environment. CoOx-doped micron-sized hollow MgO rods were prepared for the treatment of phenol wastewater by catalytic ozonation. Magnesium sources, precipitants, initial precursor concentration, Co/Mg molar ratio, and catalyst calcination temperature were optimized to obtain the best catalysts. Prepared catalysts were also well characterized by various methods to analyze their structure and physical and chemical properties. In this process, CoOx/MgO with the largest large surface area (151.3 m3/g) showed the best catalytic performance (100 and 79.8% of phenol and chemical oxygen demand (COD) removal ratio, respectively). The hydrolysis of CoOx/MgO plays a positive role in the degradation of phenol. The catalytic mechanism of the degradation of O3 to free radicals over catalysts has been investigated by in situ electronic paramagnetic resonance (EPR). The catalyst can be reused at least five times without any activity decline. The prepared CoOx/MgO catalyst also showed excellent catalytic performance for removal and degradation of ciprofloxacin, norfloxacin, and salicylic acid.

The electrochemical oxygen reduction reaction (ORR) provides a green route for decentralized H2 O2 synthesis, where a structure-selectivity relationship is pivotal for the control of a highly selective and active two-electron pathway. Here, we report the fabrication of a boron and nitrogen co-doped turbostratic carbon catalyst with tunable B-N-C configurations (CNB-ZIL) by the assistance of a zwitterionic liquid (ZIL) for electrochemical hydrogen peroxide production. Combined spectroscopic analysis reveals a fine tailored B-N moiety in CNB-ZIL, where interfacial B-N species in a homogeneous distribution tend to segregate into hexagonal boron nitride domains at higher pyrolysis temperatures. Based on the experimental observations, a correlation between the interfacial B-N moieties and HO2 - selectivity is established. The CNB-ZIL electrocatalysts with optimal interfacial B-N moieties exhibit a high HO2 - selectivity with small overpotentials in alkaline media, giving a HO2 - yield of ≈1787 mmol gcatalyst -1 h-1 at -1.4 V in a flow-cell reactor. ispartof: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION vol:61 issue:37 ispartof: location:Germany status: published

In this study, monodispersed NiRu nanocrystals with a diameter of 3 nm were synthesized at 90 °C via a tuning hot-inject method to lower the temperature of the organic phase synthesis of monodispersed nanomaterials. The key factor for the nanocrystalline formation of NiRu alloy nanocrystals was summarized in detail. Simultaneously, the synergistic effect of Ni and Ru in CO2 methanation was explored. Doping trace Ru can significantly improve the conversion rate of CO2 methanation and CH4 selectivity. The underlying mechanism was studied in detail via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), temperature-programmed hydrogen reduction (H2-TPR) and desorption (H2-TPD) tests, and temperature-programmed desorption of CO2 (CO2-TPD). This study gives out a new way for the general synthesis of monodisperse nickel-based nanocrystals and provides a reference for the development and application of monodispersed nanoparticles for CO2 methanation.

Nanoparticle drug delivery is largely restricted by the low drug loading capacity of nanoparticle carriers. To address this critical challenge and maximize the potential of nanoparticle drug delivery, a 2D ultra-thin layered double hydroxide (LDH) nanosheet with exceptionally high drug loading, excellent colloidal stability, and prolonged blood circulation for cancer treatment is constructed. The nanosheet is synthesized via a biocompatible polymer-assisted bottom-up method and exhibits an ultra-thin 2D sheet-like structure that enables a considerable amount of cargo anchoring sites available for drug loading, leading to an extraordinary 734% (doxorubicin/nanoparticle mass ratio) drug loading capacity. Doxorubicin delivered by the nanosheet remains stable on the nanosheet carrier under the physiological pH condition, while showing sustained release in the tumor microenvironment and the intracellular environment, thus demonstrating on-demand drug release as a result of pH-responsive biodegradation of nanosheets. Using in vitro and in vivo 4T1 breast cancer models, the nanosheet-based ultra-high drug-loading system demonstrates even enhanced therapeutic performance compared to the multilayered LDH-based high drug-loading system, in terms of increased cellular uptake efficiency, prolonged blood circulation, superior therapeutic effect, and reduced systemic toxicity.

Tungsten carbide (WC) with imperfect structures determined by phase engineering and heteroatom doping has attracted a great deal of attention with respect to hydrogen evolution reaction (HER). Howe...

A pilot plant with a closed cycle of the absorption/desorption process has been taken into account for the simulation of carbon dioxide (CO2) capture by piperazine (PZ) + methyldiethanolamine (MDEA) solution using Aspen Plus rate-based model with all design and operational parameters such as the hydraulic specifications of absorber and stripper as well as inlet flue gas conditions which are present in a commercial gas-fired burner for heating houses. Metal FLEXIPAC 250Y has been considered as the packing type to apply the model to the proposed correlations on Aspen Plus for calculation of flooding and pressure drop. In order to simulate the process, a new property package has been developed by electrolyte non-random two-liquid (E-NRTL) model and perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state which are used for the calculation of activity and fugacity coefficients respectively. The model has been compared with some experimental data e.g. CO2 absorption efficiency and CO2 loading and demonstrated good agreement with them.

Photoluminescent metal-organic frameworks (MOFs) were grown in a living plant (Syngonium podophyllum) via immersing their roots in an aqueous solution of disodium terephthalate and terbium chloride hexahydrate sequentially for 12 h without affecting their viability. Then, app-assisted living MOF-plant nanobiohybrids were used for the detection of various toxic metal ions and organic pollutants. Their performance and sensing mechanism were also evaluated. The results demonstrated that the living plants served as self-powered preconcentrators via their passive fluid transport systems and accumulated the pollutants around the embedded MOFs, resulting in relative changes in fluorescence intensity. Therefore, the living MOF-plant nanobiohybrids initiate superior selectivity and sensitivity (0.05-0.5 μM) in water for Ag+, Cd2+, and aniline with a "turn-up" fluorescence response and for Fe3+ and Cu2+ with "turn-down" fluorescence response in the linear range of 0.05-10 μM with excellent precision and accuracy of 5 and 10%, respectively. With the easy-to-read visual signals under ultraviolet light, the app translates plant luminescent signals into digital information on a smartphone for on-site monitoring of environmental pollutants with high sensitivity and specificity. These results suggest that interfacing synthetic and living materials may contribute to the development of smart sensors for on-site environmental pollutant sensing with high accuracy.

Off-target toxicity remains a major limitation of current cancer therapy, necessitating an alternative precision approach to treat cancers. Herein, a tumor microenvironment (TME)-triggered anticancer strategy was developed by constructing an anti-alcoholism drug disulfiram (DSF)-loaded, Cu-doped zeolite imidazolate frameworks-8 (DSF-Cu/ZIF-8) nanoparticle followed by PEGylation (PEG-DSF-Cu/ZIF-8) to realize in situ generation of cytotoxic compounds specifically in TME. The PEG-DSF-Cu/ZIF-8 demonstrated excellent hydrolytic stability in normal physiological conditions, guaranteeing the minimized off-target release of disulfiram and Cu ions. Under the TME condition, the PEG-DSF-Cu/ZIF-8 exhibited acidity-triggered biodegradation and the associated payload release, through which low-toxic compounds (disulfiram and Cu

Hydrodesulfurization of 4, 6-dimethyldibenzothiophene is of great significance for emission reduction and environmental protection. Herein, the effects of Mg addition on CoMo/Al2O3 were systematically studied for the hydrodesulfurization of 4, 6-dimethyldibenzothiophene. The CoMo/Mg-Al2O3 was formed by incorporating Mg in the alumina lattice and showed excellent hydrodesulfurization performance compared to CoMo/Mg/Al2O3 formed after deposition of Mg on the alumina surface and to CoMo/Al2O3 without introducing Mg. Experimental characterization and theoretical calculations showed that the introduction of Mg is beneficial to the formation of β-CoMoO4, which significantly promoted the production of CoMoS active sites. Meanwhile, the introduction of Mg mainly improved the medium-strong surface basic sites.

Metal–organic frameworks (MOFs) have been widely used to remove organic/toxic compounds from waste water. Ciprofloxacin (CIP) has been detected in surface and waste water, which is harmful to aquatic organisms and human body. Herein, MIL-101(Cr)-HSO3 was synthesized by solvothermal method and its structural features were characterized by XRD, SEM, FTIR, N2 adsorption–desorption analysis at 77 K and zeta potential. Then, the CIP adsorption performance of MIL-101(Cr)-HSO3 was investigated, in which the effect of adsorbent dosage, contact time, pH and ionic strength were explored. MIL-101(Cr)-HSO3 showed the highest adsorption capacity when the adsorbent dosage was 0.1 g/L and the pH was 8.0. The observation from the effects of pH and ionic strength suggested a stronger electrostatic interactions between CIP and MIL-101(Cr)-HSO3. The pseudo-second-order model fitted the adsorption kinetics data of MIL-101(Cr)-HSO3 well. Moreover, the equilibrium adsorption data of MIL-101(Cr)-HSO3 followed the Langmuir model, indicating a mono-layer adsorption of CIP onto surface of MIL-101(Cr)-HSO3. The calculated maximum CIP adsorption capacity from Langmuir model was 564.9 mg/g, which was higher than the reported materials. Besides, the equilibrium adsorption data were fitted to the Tempkin model with r2 = 0.9880, which also suggested a stronger electrostatic interaction between CIP and MIL-101(Cr)-HSO3. Finally, the introduced sulfonic acid group made the material more negatively charged on the surface, which benefited the adoption of CIP via stronger electrostatic interactions resulting the enhanced adsorption capacity of CIP. The results show that the MIL-101(Cr)-HSO3 is a promising candidate for removal of CIP and introducing proper functional groups on organic linker is a convenient way to obtain MOFs with better performance for a specific application.

Co–Mo–S based catalysts have promising applications in both hydrogen evolution reaction (HER) and hydrodesulfurization (HDS). Herein, MoS2–Co3S4 hollow polyhedrons have been successfully synthesized by the vulcanization of Mo doped ZIF-67. MoS2–Co3S4 hollow polyhedrons show the superior HER and HDS catalytic activities to pure MoS2, Co3S4 and MoS2–Co3S4 nanoparticles prepared by the traditional coprecipitation methods, owing to the both morphology effect and synergistic effect between Co3S4 and MoS2. DFT calculation studied the activation energies needed by MoS2 and Co–Mo–S for HER and HDS, respectively. The required activation energies for C–S bond fracture and H2 generation on Co–Mo–S structure are both obviously lower than that of MoS2 structure. Our work reported a new method to synthesize Co–Mo–S catalysts with large surface area and numerous active sites, and further experimentally and theoretically proved Co–Mo–S structure had better catalytic activities for both HER and HDS.

Different carbon structures (activated carbon, carbon nanotubes, graphene and graphite) were investigated for the replacement of heteropoly catalysts for the oxidation of methacrolein to methacrylic acid. Activated carbon showed the best catalytic performance with higher catalytic activity than molybdovanaphosphoric acid at lower temperatures. The catalytic performance of activated carbon was further improved by the addition of heteroatoms, such as P, B, N and S. The latter occupy the electrophilic oxygen functional groups thus preventing further oxidation of methacrylic acid and improving reaction selectivity. The best catalytic performance results were obtained on activated carbon with 10 wt% P, where methacrolein conversion, methacrylic acid selectivity and yield at 270 °C were 40.1, 70.8 and 30.3%, respectively. The results of the present work show a novel way to design non-metal catalysts for the selective oxidation of methacrolein to methacrylic acid.

Degradation of cellulose to reducing sugar is the key step for the conversion of cellulose to valuable chemicals. Cellulose was degraded by WCl6 in 1-butyl-3-methyl imidazole chloride at 80 °C and lower. 83% and 85.5% yield of total reducing sugar was gotten at 70 and 80 °C, respectively. Compared with inorganic acid, heteropoly acid, acidic ionic liquid and other metal chlorides, WCl6 has shown better catalytic performance for degradation of cellulose to reducing sugar. The effect of reaction temperature, reaction time, WCl6 amount and cellulose concentration were investigated. Degradation of cellulose by WCl6 in 1-butyl-3-methyl imidazole chloride is a zero reaction. WCl6 also showed excellent catalytic performance for the degradation of nature cellulose and lignocellulose. Catalyst can be reused at least 5 times without decrease of reducing sugar yield. The mechanism of degradation of WCl6 was also suggested.