查找使用阿拉丁产品的科研文献

Effect of Persulfate Activation by Electrogenerated H2O2 and Anodic Oxidation on the Color Removal of Dye Solutions at Pt and BDD Anodes

Yifan Yao,Kai Zhu,Yucan Liu,Qianjin Liu,Lihua Huang

In this study, tartrazine solutions were oxidized using innovative electrochemical advanced oxidation processes (EAOPs) that combined persulfate (PS) activation with electrogenerated H2O2, cathodic reduction and anodic oxidation at Pt and BDD anodes, and graphite cathode in an undivided stirred reactor. For the Pt anode, SO4·−was generated from a reduction reaction at the cathode and a reaction between the PS and electrogenerated H2O2. For the BDD anode, SO4·−was generated from a reduction reaction at the cathode, an oxidation reaction at the anode, and a reaction between PS and electrogenerated H2O2. Among these activation methods, the activation efficiency of PS by electrogenerated H2O2is much better than other methods. The effects of PS concentration up to 36 mM, applied current density between 6 to 15 mA cm−2,and temperatures between 25 to 45 °C were investigated. For the electro-Fenton process with Pt anode (Pt-H2O2/PS process), the best result for oxidizing 250 mg L−1tartrazine solution was obtained with 37.5 mM Na2SO4+ 9.0 mM Na2S2O8, applied current density at 12 mA cm−2and 45 °C, acquiring total color removal after 30 min reaction. For the electro-Fenton process with BDD anode (BDD-H2O2/PS process), the best result for oxidizing 250 mg L−1tartrazine solution was obtained with 25 mM Na2SO4+ 18 mM Na2S2O8, applied current density at 12 mA cm−2and 45 °C, yielding 100% color removal after 30 min reaction. The main oxidizing agents are SO4·−and OH·in the anodic oxidation process with PS and the electro-Fenton process with PS. It is concluded that the additions of PS tremendously improve the oxidation power of electro-Fenton processes with PS, especially the Pt-H2O2/PS process.Keywords:anodic oxidation;electrogenerated H2O2;persulfate;hydroxyl radical;sulfate radical

Combination of coagulation, Fe0/H2O2 and ultra-high lime aluminium processes for the treatment of residual pollutants in biologically-treated landfill leachate

Xue Bai,Shiqi Mu,Bowen Song,Mingde Xie

Highly efficient electro-peroxone enhanced by oxygen-doped carbon nanotubes with triple role of in-situ H2O2 generation, activation and catalytic ozonation

Jinyu Gu,Jinxin Xie,Shasha Li,Ge Song,Minghua Zhou

The oxygen-doped carbon nanotubes coated on the carbon felt acted as cathode to enhance the electro-peroxone (OCNT-EP) process. Owing to the introduction of oxygen-containing functional groups and defect sites, the OCNT modified cathode could achieve in-situ H 2 O 2 generation, activation, and catalytic ozonation in the EP process. The OCNT-EP showed a 2.3-folds apparent first-order rate constant ( k ) compared with the EP process using CNT cathode (CNT-EP) for atrazine (ATZ) degradation. According to the processes comparison, quenching experiments, electron paramagnetic resonance (EPR) analysis and determination of hydroxyl radical, it was proved that more . OH and 1 O 2 were generated by the in-situ H 2 O 2 activation and catalytic ozonation in the OCNT-EP process. Especially, this process improved pollutants degradation under acidic condition for the in-situ H 2 O 2 activation and catalytic ozonation, expanding the pH application range of the EP process with a lower energy consumption (0.10 kWh/g ATZ). What’ more, the OCNT modified cathode performed excellent stability with 20 cycle tests, and demonstrated all improved degradation rate (21.7%−78.0%) for various pollutants (carbamazepine, sulfamethazine, phenol and 2,4-dichlorophenol). Therefore, the OCNT-EP process could be considered as a promising and enhanced EP process for wastewater treatment.

The degradation of municipal solid waste incineration leachate by UV/persulfate and UV/H2O2 processes: The different selectivity of SO4•- and •OH

Pengfei Gan,Yichun Sun,Yunyi Li,Wen Liu,Jiangyu Ye,Meiping Tong,Jialiang Liang

In this work, the different selectivity of SO 4 •- and • OH towards municipal solid waste incineration leachates (MSWILs) was studied by a comparative study of UV/persulfate (PS) and UV/H 2 O 2 . Results showed SO 4 •- preferentially mineralized carbon atoms of higher average oxidation state, while • OH showed a two-stage mechanism of partial oxidation and mineralization successively. Electron spin resonance (ESR) analysis showed SO 4 •- had superior selectivity towards MSWILs than • OH, and Fe(II) would significantly affect the selectivity via forming Fe-MSWILs complex. As the consequence, Fe(II) showed slightly negative effect on UV/PS, but greatly enhanced the performance of UV/H 2 O 2 /Fe(II). High concentration of Cl - affected the degradation of non-fluorescent substances by UV/PS, while SO 4 2 - and NO 3 - showed no effect. In contrast, anions showed no effect on UV/H 2 O 2 . In addition, • OH preferentially attacked large molecules, but SO 4 •- showed no selectivity. This study further revealed the selectivity of SO 4 •- and • OH in the treatment of hypersaline wastewater, and provided theoretical support for the development of targeted technology .

A unique colorimetric and ratiometric reversible fluorescent probe for HSO3−/H2O2 detection and imaging in real water samples, rice leaves and roots

Jian Wang,Haoyang Li,Weibo Xu,Bo Zhang,Yu Wang,Nan Chen,Qinghai Zhou,Tianrui Ren

A reversible colorimetric and ratiometric fluorescent probe ( QG-Py ) was developed for HSO 3 − detection. The probe showed large changes in absorbance and emission wavelength shift both with 155 nm when reacted with NaHSO 3 . Furthermore, probe QG-Py exhibited high selectivity and sensitivity to NaHSO 3 with quantitative analysis in real water samples through colorimetric and ratiometric methods. Interestingly, the reaction product ( QG-Py-SO 3 H ) displayed structural recovery to QG-Py induced by H 2 O 2 , accompanied with reversible optical properties . Probe QG-Py was established to visualize HSO 3 − /H 2 O 2 in MCF-7 cells. Importantly, QG-Py was also successfully applied for HSO 3 − /H 2 O 2 detection and imaging in rice roots and leaves, providing better understanding of the influence of SO 2 derivatives to crops, as well as a new and simple method for evaluating environmental pollution of SO 2 .

Tumor microenvironment-activated single-atom platinum nanozyme with H2O2 self-supplement and O2-evolving for tumor-specific cascade catalysis chemodynamic and chemoradiotherapy

Qiqi Xu,Yuetong Zhang,Zulu Yang,Guohui Jiang,Mingzhu Lv,Huan Wang,Chenghui Liu,Jiani Xie,Chengyan Wang,Kun Guo,Zhanjun Gu,Yuan Yong

Nanozyme-based tumor collaborative catalytic therapy has attracted a great deal of attention in recent years. However, their cooperative outcome remains a great challenge due to the unique characteristics of tumor microenvironment (TME), such as insufficient endogenous hydrogen peroxide (H 2 O 2 ) level, hypoxia, and overexpressed intracellular glutathione (GSH). Methods: Herein, a TME-activated atomic-level engineered PtN 4 C single-atom nanozyme (PtN 4 C-SAzyme) is fabricated to induce the “butterfly effect” of reactive oxygen species (ROS) through facilitating intracellular H 2 O 2 cycle accumulation and GSH deprivation as well as X-ray deposition for ROS-involving CDT and O 2 -dependent chemoradiotherapy. Results: In the paradigm, the SAzyme could boost substantial ∙OH generation by their admirable peroxidase-like activity as well as X-ray deposition capacity. Simultaneously, O 2 self-sufficiency, GSH elimination and elevated Pt 2+ release can be achieved through the self-cyclic valence alteration of Pt (IV) and Pt (II) for alleviating tumor hypoxia, overwhelming the anti-oxidation defense effect and overcoming drug-resistance. More importantly, the PtN 4 C-SAzyme could also convert O 2 ·- into H 2 O 2 by their superior superoxide dismutase-like activity and achieve the sustainable replenishment of endogenous H 2 O 2 , and H 2 O 2 can further react with the PtN 4 C-SAzyme for realizing the cyclic accumulation of ∙OH and O 2 at tumor site, thereby generating a “key” to unlock the multi enzymes-like properties of SAzymes for tumor-specific self-reinforcing CDT and chemoradiotherapy. Conclusions: This work not only provides a promising TME-activated SAzyme-based paradigm with H 2 O 2 self-supplement and O 2 -evolving capacity for intensive CDT and chemoradiotherapy but also opens new horizons for the construction and tumor catalytic therapy of other SAzymes.

Synergetic effects of Sn and Ti incorporated in MWW zeolites on promoting the oxidative hydration of ethylene with H2O2 to ethylene glycol

Wen Xu,Xiaoshu Wang,Weilong Hou,Kang Tang,Xinqing Lu,Yijing Gao,Rui Ma,Yanghe Fu,Weidong Zhu

Although the titanosilicate zeolite catalyzed one-pot oxidative hydration of ethylene with hydrogen peroxide (H 2 O 2 ) to ethylene glycol (EG) takes advantages of step-saving and facile operation, both H 2 O 2 utilization efficiency and EG yield are relatively low. In the present work, Sn-doped Ti-MWW zeolites, named Sn-Ti-MWW, were developed for this oxidative hydration, showing the much higher H 2 O 2 utilization efficiency and EG yield, compared to Ti-MWW. The extensive characterizations of Sn-Ti-MWW zeolites, in combination with Density Functional Theory (DFT) calculations, verify that the doping of Sn into Ti-MWW leads to the higher electropositivity of the Ti species, resulting in the stronger acidity of the zeolite, which is helpful to the H 2 O 2 utilization and EG production. In addition, although the catalyst deactivation is observed due to the deposition of the bulky byproducts onto the active sites and/or into the zeolite micropores, the simple calcination of the used catalyst readily restores its catalytic activity. Therefore, it is anticipated that the developed Sn-Ti-MWW catalyst might be applicable in the one-pot oxidative hydration of ethylene with H 2 O 2 to EG industrially.

Enhancing H2O2 and glucose double detection by surface microstructure regulation of Brussels sprout-like Ni–Co(OH)2/rGO/carbon cloth composites

Xinmeng Zhang,Zixuan Mao,Wanyin Ge,Jiajing Zhu,Yuanxiao Zhao

Surface microstructure regulation is an effective way to enhance the performance of sensing materials. Here, a hierarchical and flexible Brussels sprout-like Ni–Co(OH)2/rGO/carbon cloth (CC) composite was constructed by optimizing the morphology of Ni–Co(OH)2 microspheres and the addition amount of rGO. This sensor shows excellent reproducibility, high selectivity, and good stability. It shows a high sensitivity of 3.7391 mA mM−1 cm−2 in the 0.0388–124.0436 mM line detection range for H2O2 and 1.8457 mA mM−1 cm−2 in the 0.0300–2.0000 mM line detection range for glucose. The low limits of detection for H2O2 and glucose are 2.316 nM and 0.115 μM, respectively. The excellent electrochemical performance of the Ni–Co(OH)2/rGO/CC composite is attributed to its unique Brussels sprout-like microstructure. By studying the electrical conductivity, electrochemical active surface area, and hydrophilic–hydrophobic surfaces of the Ni–Co(OH)2/rGO/CC composite, the structure–performance relationship between the microstructure and sensing performance of the composite was further clarified. Moreover, the mechanism of CC, rGO, and the Ni–Co(OH)2 ternary composite in the sensing process is proposed. This study provides a new strategy for the construction of flexible wearable electrodes with high sensitivity.

Co–N/C-900 metal–organic framework-derived nanozyme as a H2O2-free oxidase mimic for the colorimetric sensing of L-cysteine

Jian Chen,Song Hu,Yongliang Cai,Xia Liu,Yueqi Wu,Yihu Dai,Zhijuan Wang

Nanozymes have attracted considerable attention as a new type of promising artificial enzyme in recent years. Here, an oxidase-like cobalt–nitrogen–carbon (Co–N/C-900) nanozyme with well-regulated metal atom spatial distribution has been derived from Co–Zn bimetal zeolitic imidazolate framework precursors and used to develop a facile colorimetric sensing method for L-cysteine. With the aid of Co–N/C-900, the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) was oxidized to blue oxidized TMB in the absence of H2O2. However, the oxidation was inhibited after the addition of L-cysteine, and the blue color faded to colorless. Thus, Co–N/C-900 exhibited quite good oxidase-like activity with high catalytic efficiency. Therefore, a facile and efficient colorimetric method to sensitively determine L-cysteine with a low detection limit of 33 nM (S/N = 3) has been developed. Furthermore, favorable selectivity and anti-interference ability towards the determination of L-cysteine based on this approach have also been achieved. It is believed that this colorimetric method for the detection of L-cysteine based on Co–N/C-900 will show potential applications in bioscience and bioengineering.

Understanding the selectivity trend of water and sulfate (SO42−) oxidation on metal oxides: On-site synthesis of persulfate, H2O2 for wastewater treatment

Zhen Chen,Shipeng Geng,Juan Xiao,Fengyue Zhao,Kun Wang,Yi Wang,Panagiotis Tsiakaras,Shuqin Song

Herein, H 2 O 2 production activity via two-electron water oxidation reaction is identified on metal oxides (WO 3 , TiO 2 , and BiVO 4 ) in acidic SO 4 2− involving electrolyte, in which persulfate (PS) acts as an intermediate. A deep understanding of mechanism of PS production reaction on metal oxides has been realized based on rigorous crystal plane analysis of WO 3 and TiO 2 by combining density functional theory calculations and zeta potential measurements. It is found that the binding-energy of adsorbed hydroxyl groups on dominant exposed crystal plane of WO 3 is lower than that of TiO 2 , leading to more SO 4 2− adsorption sites at the surface of WO 3 . Consequently, the formation of PS on WO 3 surface is more favorable. Meanwhile, both SO 4 − · and OH· were detected in the electrolyte by electron paramagnetic resonance measurement, which play a crucial role in organic pollutants wastewater treatment, with a degradation efficiency of 96% in 90 min for a typical pollutant norfloxacin. This work can provide a novel insight for understanding the selectivity of water and SO 4 2− species oxidation on metal oxides, and open a new way for both on-site H 2 O 2 production and advanced oxidation processes application.

The multifunctional BODIPY@Eu-MOF nanosheets as bioimaging platform: A ratiometric fluorescencent sensor for highly efficient detection of F-, H2O2 and glucose

Yang Li,Jia-Jia Li,Qing Zhang,Jian-Yong Zhang,Na Zhang,Yong-Zheng Fang,Jinwu Yan,Qinfei Ke

The highly emissive BODIPY (boron-dipyrromethene) have been grafted on the Eu-based metal-organic frameworks (Eu-MOFs) via the covalent F-B bonding using a facile one-pot solvothermal reaction. The fluorescence emission ratio of [email protected] has been applied to construct the ratiometric fluorescence sensor for the F - , H 2 O 2 and glucose detection in water solution and living cells. The produced [email protected] probe provided enhanced sensitivity, higher selectivity and lower lower limits of detection (LOD) for the detection of F - (0.1737 μM), H 2 O 2 (6.22 nM) and glucose (6.92 nM), and 5.96, 6.52 and 6.95 times lower than that for single Eu-MOF, respectively. More importantly, the probe also exhibited the lower biotoxic in living cells for bioimaging and the better visualization performance with multiplex channels. The results indicated the π-conjugated BODIPY derivative not only acted as the surfactant molecule or template agent for preferred growth, but also modulated the fluorescent emissions drastically, and thus induced excellent fluorescent detecting performances.

A H2O2-activatable nanoprobe for diagnosing interstitial cystitis and liver ischemia-reperfusion injury via multispectral optoacoustic tomography and NIR-II fluorescent imaging

Chen Junjie,Chen Longqi,Wu Yinglong,Fang Yichang,Zeng Fang,Wu Shuizhu,Zhao Yanli

Developing high-quality NIR-II fluorophores (emission in 1000–1700 nm) for in vivo imaging is of great significance. Benzothiadiazole-core fluorophores are an important class of NIR-II dyes, yet ongoing limitations such as aggregation-caused quenching in aqueous milieu and non-activatable response are still major obstacles for their biological applications. Here, we devise an activatable nanoprobe to address these limitations. A molecular probe named BTPE-NO 2 is synthesized by linking a benzothiadiazole core with two tetraphenylene groups serving as hydrophobic molecular rotors, followed by incorporating two nitrophenyloxoacetamide units at both ends of the core as recognition moieties and fluorescence quenchers. An FDA-approved amphiphilic polymer Pluronic F127 is then employed to encapsulate the molecular BTPE-NO 2 to render the nanoprobe BTPE-NO 2 @F127. The pathological levels of H 2 O 2 in the disease sites cleave the nitrophenyloxoacetamide groups and activate the probe, thereby generating strong fluorescent emission (950~1200 nm) and ultrasound signal for multi-mode imaging of inflammatory diseases. The nanoprobe can therefore function as a robust tool for detecting and imaging the disease sites with NIR-II fluorescent and multispectral optoacoustic tomography (MSOT) imaging. Moreover, the three-dimensional MSOT images can be obtained for visualizing and locating the disease foci.