查找使用阿拉丁产品的科研文献

Photocatalytic selective oxidation of aromatic alcohols coupled with hydrogen evolution over CdS/WO3 composites

Yu-Lan Wu,Ming-Yu Qi,Chang-Long Tan,Zi-Rong Tang,Yi-Jun Xu

ABSTRACT Simultaneously utilizing photogenerated electrons and holes to convert renewable biomass and its derivatives into corresponding value-added products and hydrogen (H 2 ) is a promising strategy to deal with the energy and environmental crisis. Herein, we report a facile hydrothermal method to construct a direct Z-scheme CdS/WO 3 binary composite for photocatalytic coupling redox reaction, simultaneously producing H 2 and selectively converting aromatic alcohols into aromatic aldehydes in one pot. Compared with bare CdS and WO 3 , the CdS/WO 3 binary composite exhibits significantly enhanced performance for this photocatalytic coupled redox reaction, which is ascribed to the extended light harvesting range, efficient charge carrier separation rate and optimized redox capability of CdS/WO 3 composite. Furthermore, the feasibility of converting various aromatic alcohols to corresponding aldehydes coupled with H 2 evolution on the CdS/WO 3 photocatalyst is proved and a reasonable reaction mechanism is proposed. It is hoped that this work can provide a new insight into the construction of direct Z-scheme photocatalysts to effectively utilize the photogenerated electrons and holes for photocatalytic coupled redox reaction.

Bacterial Inactivation and Biofilm Disruption through Indigenous Prophage Activation Using Low-Intensity Cold Atmospheric Plasma

Xia Gu,Dan Huang,Juhong Chen,Xiang Li,Yongquan Zhou,Manhong Huang,Yanan Liu,Pingfeng Yu

Biofilms can be pervasive and problematic in water treatment and distribution systems but are difficult to eradicate due to hindered penetration of antimicrobial chemicals. Here, we demonstrate that indigenous prophages activated by low-intensity plasma have the potential for efficient bacterial inactivation and biofilm disruption. Specifically, low-intensity plasma treatment (i.e., 35.20 W) elevated the intracellular oxidative reactive species (ROS) levels by 184%, resulting in the activation of prophage lambda (λ) within antibiotic-resistant Escherichia coli K-12 (lambda+) [E. coli (λ+)]. The phage activation efficiency was 6.50-fold higher than the conventional mitomycin C induction. Following a cascading effect, the activated phages were released upon the lysis of E. coli (λ+), which propagated further and lysed phage-susceptible E. coli K-12 (lambda−) [E. coli (λ−)] within the biofilm. Bacterial intracellular ROS analysis and ROS scavenger tests revealed the importance of plasma-generated ROS (e.g., •OH, 1O2, and •O2–) and associated intracellular oxidative stress on prophage activation. In a mixed-species biofilm on a permeable membrane surface, our “inside-out” strategy could inactivate total bacteria by 49% and increase the membrane flux by 4.33-fold. Furthermore, the metagenomic analysis revealed that the decrease in bacterial abundance was closely associated with the increase in phage levels. As a proof-of-concept, this is the first demonstration of indigenous prophage activations by low-intensity plasma for antibiotic-resistant bacterial inactivation and biofilm eradication, which opens up a new avenue for managing associated microbial problems.

Efficient peroxymonosulfate activation by CuO-Fe2O3/MXene composite for atrazine degradation: Performance, coexisting matter influence and mechanism

Peng Xu,Peng Wang,Xiang Li,Rui Wei,Xiaojing Wang,Chunyan Yang,Tianyao Shen,Tong Zheng,Guangshan Zhang

CuO-Fe 2 O 3 /MXene was fabricated using a rapid microwave hydrothermal method and used for the enhanced peroxymonosulfate (PMS) activation and atrazine (ATZ) degradation. The ATZ degradation rate could reach up to nearly 100% within 60 min at pH = 6.4, with low dosage for CuO-Fe 2 O 3 /5% MXene (0.1 g‧L -1 ) and PMS (0.37 mM). Experimental results and DFT calculations showed that coexisting matter had little influence on ATZ degradation at low concentrations, indicating the excellent anti-interference capability of the system. Circulation and interaction of ≡Fe(III)/≡Fe(II) and ≡Cu(II)/≡Cu(I) produced SO 4 •- and •OH, O* and SO 5 •- could participate in the formation of 1 O 2 . Then, ATZ degradation pathways, including dealkylation, dichlorination-hydroxylation, alkyl hydroxylation, alkyl oxidation, olefination, and deamination-hydroxylation processes, were proposed based on DFT calculations and ESI-QTOF-MS/MS data. QSAR analysis illustrated that most intermediates were more environmentally friendly than ATZ. This study developed novel materials with superior catalytic performance for elimination of refractory organic pollutants in wastewater.

Controllable Microemulsion Synthesis of Hybrid TiO2–SiO2 Hollow Spheres and Au-Doped Hollow Spheres with Enhanced Photocatalytic Activity

Qiangtao Zhu,Dongyu Pan,Yangyi Sun,Dongming Qi

Hollow structures in TiO2 materials can enhance the photocatalytic properties by reducing the diffusion length and improving the accessibility of active sites for the reactants. However, existing approaches for preparing hollow TiO2 materials have two drawbacks that restrict their engineering applicability: first, a heavy reliance on templates to form a hollow structure, which makes the preparation laborious, complicated, and costly; second, difficult-to-achieve high crystallization while maintaining the small grain size in calcinated TiO2, which is crucial for enhancing photocatalytic activity. Herein, a simple, effective method is proposed that not only enables the preparation of hybrid TiO2–SiO2 hollow spheres without the template fabrication and removal process via microemulsion technology but also achieves both high crystallization and a small grain size in calcinated TiO2 at once through the calcination of amorphous TiO2 with organosilane at a high temperature of 850 °C. The prepared TiO2–SiO2 hollow spheres with tunable sizes demonstrate high photocatalytic activity with a maximum k value of 133.74 × 10–3 min–1, which is superior to commercial photocatalyst P25 (k = 114.97 × 10–3 min–1). In addition, Au can be doped in the hybrid TiO2–SiO2 shell to gain Au-doped hollow spheres that show a high k value of up to 694.14 × 10–3 min–1, which is 6 times larger than that of P25 and much better than that reported in the literature. This study not only provides an effective approach to stabilize and tune the grain growth of the TiO2 photocatalyst during calcination but also enables the simple preparation of hollow TiO2-based materials with controllable hollow nanostructures.

A novel colorimetric strategy for rapid detection of dimethoate residue in vegetables based on enhancing oxidase-mimicking catalytic activity of cube-shape Ag2O particles

Xiangqiang Zhan,Yue Tang,Yuanyuan Liu,Han Tao,Yuangen Wu

Although many colorimetric methods have been established for pesticide analysis, most of them rely on inhibiting catalytic activities of natural enzymes or nanozyme , easily leading to false positives in results of pesticide detection. Herein, a simple, stable, and rapid colorimetric method was firstly proposed to detect pesticide residues in vegetables based on enhancing the oxidase-mimicking activity of cube-shape Ag 2 O. The experiments, including fluorescence probe, electrochemistry , free radical tracking and enzymatic kinetics, confirmed that dimethoate could promote electron transfer from Ag 2 O to dissolved oxygen and accelerate the release of·O 2 - radicals as well as 1 O 2 , facilitating the catalytic oxidation of the chromogenic substrate. The colorimetric method exhibited satisfactory sensitivity with the limit of detection as low as 14 μg·L −1 . Moreover, such method showed excellent selectivity against other competitive pesticides, and achieved good recovery in several typical vegetables, which indicate that such strategy has a bright application prospect in the field of pesticide detection in food.

Heat-activated peracetic acid for degradation of diclofenac: kinetics, influencing factors and mechanism

Jiewen Deng,Shenglan Liu,Yongsheng Fu,Yiqing Liu

Efficient peroxymonosulfate activation through a simple physical mixture of FeS2 and WS2 for carbamazepine degradation

Ge Gou,Shurui Kang,Hailing Zhao,Chao Liu,Naiwen Li,Bo Lai,Jun Li

In this study, carbamazepine (CBZ) degradation was evaluated by peroxymonosulfate (PMS) activation after the simultaneous introduction of FeS 2 and WS 2 . For FeS 2 /WS 2 /PMS system, 99% of CBZ was removed within 40 min under the conditions of 100 mg/L FeS 2 , 150 mg/L WS 2 , 0.2 mM PMS, and initial pH 6.7. The apparent rate constant ( k obs ) of CBZ degradation in the FeS 2 /WS 2 /PMS system (0.108 min −1 ) was about 3.0- and 13.5-folds of that in FeS 2 /PMS system (0.036 min −1 ) and WS 2 /PMS system (0.008 min −1 ). Quenching experiments and electron paramagnetic resonance (EPR) experiments indicated that hydroxyl radical, sulfate radical , superoxide radical, and singlet oxygen participated in the CBZ degradation. The catalytic reaction mechanism was proposed, and W on the surface of WS 2 was the main reactive site to accelerate the regeneration of Fe(II) in the FeS 2 , which played a dominant role in PMS activation. The degradation pathways of CBZ in the FeS 2 /WS 2 /PMS system were put forward, and the ecotoxicity of CBZ and its degradation by-products was evaluated. A distinguishing performance of CBZ degradation in the successive six runs was shown. The work indicated the FeS 2 /WS 2 /PMS system was an efficient advanced oxidation process with promising engineering application due to its simple operation, high efficiency, and stability for the degradation of the organics from water.

Transformation of houttuynia cordata into a surface-loaded cobalt/biocarbon activated peroxymonosulfate for degradation of chlortetracycline

Chun-Sheng OuYang,Jing Tan,Chao Zhang,Hao Bi

Peroxymonosulfate (PMS) has attracted great interest over the past few years owing to its great capacity and versatility for the breakdown of developing antibiotic contaminants. It is under intensive investigation for its potential for alternative advanced oxidation processes (AOPs) in wastewater treatment. In this study, we used activated cobalt-doped carbon as a new and excellent metal catalyst to activate PMS. The synthesis of novel Co 3 O 4 @C-900 hybrids with numerous active interfaces and superior surface electron transfer was achieved. Co 3 O 4 @C-900 and carbon matrix mixed evenly to create a stable catalytic structure. The Co 3 O 4 @C-900 structure equipped them with enhanced catalytic efficacy, thus decreasing environmental harm during actual Chlortetracycline (CTC) degradation. The CTC removal rate reached 100% within 10 min, exhibiting outstanding stability and high efficiency of Co 3 O 4 @C-900 hybrids. Additionally, we elucidated the PMS activation mechanism by Co 3 O 4 @C-900 via electron paramagnetic resonance (EPR) spectroscopy, radical quenching studies, and characterization analyses. Free radical quenching experiments and EPR spectroscopy revealed that the degradation of CTC by the Co 3 O 4 @C-900 PMS system was a concomitant process of free-radical and non-radical reactions. The free-radical reactions were based on the activation of PMS by Co 3 O 4 @C-900 to generate O 2 - , SO 4 - and OH, whereas the non-radical reactions were based on the activation of PMS by C to generate the active species 1 O 2 . Therefore, this study presents Co 3 O 4 @C-900 as a promising candidate for PMS activation and also demonstrates a novel mechanism of CTC degradation.

ZIF-8 derived boron, nitrogen co-doped porous carbon as metal-free peroxymonosulfate activator for tetracycline hydrochloride degradation: Performance, mechanism and biotoxicity

Jinling Xie,Xuan Luo,Liu Chen,Xiaobo Gong,Lingrui Zhang,Jing Tian

Boron and nitrogen co-doped porous carbon material (B-NPC) derived from zeolitic imidazolate frameworks (ZIF-8) was well prepared, characterized, and performed as an excellent metal-free carboncatalyst to activate peroxymonosulfate (PMS) for tetracycline hydrochloride (TC) degradation. Almost 100% of TC was removed within 60 min using 10 mg B-NPC, 20 mg PMS at 25 ℃. The co-doping of boron and nitrogen significantly improved the catalytic performance of PMS activation . The co-doping of B, N not only provided abundant active sites, but also enhanced the specific surface area and porous structure. Furthermore, free radicals combined with the non-radical mechanism worked together in B-NPC/PMS system to efficiently degrade TC. The B species, pyridinic N and graphite N on carbon matrix played major roles in activating PMS and degrading TC. Coexisting ions, humic acid and water qualities barely affected TC degradation efficiency in B-NPC/PMS system. Metal-free B-NPC catalysts also showed excellent reusability and notable adaptability to various pollutants. Moreover, possible TC degradation pathways were proposed. The main intermediate and final products showed significant decrease in biotoxicity compared to TC. This study provides a novel strategy for designing efficient metal-free PMS activator to degrade antibiotics in wastewater.

Evaluation of copper(I)-doped zinc oxide composite nanoparticles on both gram-negative and gram-positive bacteria

Jing Kong,Sufen Zhang,Ming Shen,Jingui Zhang,Sabesan Yoganathan

Antibiotic resistance is a serious problem all over the world. Inorganic metal oxide nanoparticles are suitable substitutional treatments for organic antibiotic-resistant bacterial infections. Various copper dopped ZnO nanocomposites were prepared with chemical deposition method in aqueous solution. X-ray diffraction (XRD) coupled with energy dispersive spectroscopy results reveals that cuprous oxide is uniformly doped on the surface of ZnO nanoparticles , forming Cu 2 O/ZnO nanocomposites. In addition, from Transmission electron microscopy (TEM) and scanning electron microscopy analysis , the average size of prepared Cu 2 O/ZnO composite is about 30 nm. The antibacterial activity of the Cu 2 O/ZnO composite was examined on two bacteria strains: Gram-positive Staphylococcus aureus ( S. aureus ) and Gram-negative Escherichia coli ( E. coli ). When the doping amount of Cu 2 O reaches more than 5%, a 3.58 log-reduction of S. aureus growth under visible light within 30 mins treatment was observed. The antibacterial activity of Cu 2 O/ZnO is 2.7-fold higher than pure ZnO and killing bacteria on E. coli with a 1.0 log-reduction in viability. Meanwhile, the bacteriological properties of Cu doped ZnO composites with different valence states (Cu 2+ , CuO, Cu 2 O, and Cu 0 ) were compared. Furthermore, the antibacterial mechanism was further discussed in this paper.

Highly efficient adsorption and catalytic degradation of aflatoxin B1 by a novel porous carbon material derived from Fe-doped ZIF-8

Yaqi Zhang,Yaming Sun,Yong Man,Hang Yuan,Renyong Zhao,Guoqiang Xiang,Xiuming Jiang,Lijun He,Shusheng Zhang

The development of peroxymonosulfate (PMS) catalysts with sufficient active sites and high mass transfer capacity is a desirable but challenging aspect in advanced oxidation processes. In this work, an Fe/N-co-doped porous carbon (Fe/N-PC) material derived from silica-coated Fe-doped zeolitic imidazolate framework-8 (Fe-ZIF-8) was developed and used as catalyst for the degradation of aflatoxin B 1 (AFB 1 ). Fe-ZIF-8 introduced additional Fe-N sites with high catalytic PMS activity. Importantly, the strategy of silica coating on the surface of Fe-ZIF-8 effectively prevented the aggregation of catalyst particles during the pyrolysis process and introduced a hierarchical porous structure in Fe/N-PC, significantly improving the mass transfer of reactants on the catalyst. As a result, Fe/N-PC possessed a much higher adsorption capacity for AFB 1 (202.8 mg g −1 ) than other reported carbon adsorbents and exhibited fast degradation of AFB 1 with ultra-high removal efficiency (99.88%) within 30 min. Singlet oxygen ( 1 O 2 ) was proved to be the dominant reactive species for AFB 1 degradation. In addition, four degradation products were identified, and two possible degradation pathways were proposed. The double bond of the terminal furan ring or the methoxy group was destroyed, which implied that the toxicity of the degradation products was significantly reduced. Based on the above results, Fe/N-PC can be considered an efficient catalyst for the removal of hard-to-degrade AFB 1 in practical applications.

Peroxidase-like Active Nanomedicine with Dual Glutathione Depletion Property to Restore Oxaliplatin Chemosensitivity and Promote Programmed Cell Death

Feng Wu,Yaqian Du,Jiani Yang,Boyang Shao,Zhensheng Mi,Yuanfei Yao,Ying Cui,Fei He,Yanqiao Zhang,Piaoping Yang

The nanocatalytic activity of nanozymes provides a vision for tumor treatment. However, the glutathione (GSH)-related antioxidant defense system (ADS) formed on the basis of excessive GSH in the tumor microenvironment limits its catalytic activity. Here, dendritic mesoporous silica nanoparticles (DMSNs) were employed as nanocarrier; ultrasmall Fe3O4 nanoparticles, Mn2+ ions, and glutaminase inhibitor Telaglenastat (CB-839) were subsequently integrated into large mesopores of DMSNs, forming DMSN/Fe3O4–Mn@CB-839 (DFMC) nanomedicine. This nanomedicine exhibits peroxidase mimicking activities under acidic conditions, which catalyzes the decomposition of hydrogen peroxide (H2O2) into hydroxyl radical (•OH). This also promotes the formation of lipid peroxides, which is required for ferroptosis. Furthermore, this nanomedicine can effectively deplete the existing GSH, thereby enhancing reactive oxygen species (ROS)-mediated tumor catalytic therapy. Moreover, the introduced CB-839 blocks the endogenous synthesis of GSH, further enhancing GSH depletion performance, which reduces the excretion of oxaliplatin (GSH-related resistance) from tumor cells, thereby restoring the chemical sensitivity of oxaliplatin. The dual GSH depletion property significantly weakens the GSH-related ADS and restores the chemical sensitivity of oxaliplatin, leading to the high DFMC-induced apoptosis and ferroptosis of tumor cells. Our developed nanomedicine based on integrated nanotechnology and clinical drug may aid the development of tumor treatment.