查找使用阿拉丁产品的科研文献

MXene/Cellulose Hydrogel Composites: Preparation and Adsorption Properties of Pb2+

Qiang Yang,Jia Zhang,Hairong Yin,Junkang Guo,Shenghua Lv,Yaofeng Li

In this work, acrylic cellulose hydrogel, a typical natural polymer adsorbent, was modified using MXene through in situ polymerization to create a synthetic inorganic–polymer composite known as MXene/cellulose hydrogel. FTIR, XRD, SEM, and thermogravimetric analyses were applied to characterize the chemical structure and micromorphology. The MXene/cellulose hydrogel was utilized for the removal of Pb2+from wastewater. Under optimal experimental conditions (initial Pb2+concentration of 0.04 mol/L, adsorption time of 150 min, pH = 5.5, and MXene doping content of 50% at 30 °C), a maximum adsorption capacity of 410.57 mg/g was achieved. The MXene/cellulose hydrogel corresponded with the pseudo-second-order kinetic equation model and exhibited a better fit with the Freundlich isotherm model.

MXene functionalized whispering gallery mode microbubble resonator for Pb2+ sensing

Lu Cai,Yu-xiao Liu,Hao Jing,Li-ke Li,Kai Gao,Jin-ze Zhang,Yu-jie Wang,Si-rui Huang

This study proposes a novel optical fiber sensor that integrates two-dimensional MXene materials with a microbubble whispering gallery mode (WGM) resonator for the detection of lead ions (Pb 2+ ). Utilizing the inherent negative surface charge of MXene nanosheets, a uniform functionalized film was formed on the inner surface of the microbubble cavity, enabling specific binding to Pb 2+ . Experimental results demonstrated a nonlinear response ( R 2  > 0.99) over a Pb 2+ concentration range of 0–1000 mg/L, with a detection limit of 5 mg/L, meeting the standard requirements for monitoring lead ions in industrial wastewater. The sensor also exhibits high selectivity toward Pb 2+ in the presence of interfering ions such as Zn 2+ , Ni 2+ , and Cd 2+ . Furthermore, owing to the inherent microfluidic channel of the microbubble cavity, this structure is suitable for real-time monitoring in complex aqueous environments, highlighting the great potential of the MXene-microbubble resonator platform for environmental heavy metal detection.

Peptide-based system for sensing Pb2+ and molecular logic computing

Jiao Yang Lu,Fu Rui Zhang,Wen Zi Zou,Wei Tao Huang,Zhen Guo

Peptides with recognition, assembly, various activities exhibit strong power and application prospects in sensing, material science, biomedicine . However, peptide-based sensing and expanding application is still at an early stage. Herein, a peptide-based sensing and logic system was developed for highly sensitive and selective detection of Pb 2+ and implementation of logic operations. Our Pb 2+ assay method was ultra-rapid (less than 1 min), direct, simple with detection limit of 0.75 nM. Flexibility and scalability of peptide-based solution system facilitated the execution of sensing and logic operations from simple to complex. This research will not only inspire discovery and comprehensive applications (such as sensing and assembly) of more functional peptides, but also provide more opportunities for development and design of peptide-based systems and molecular information technologies.

Adsorption and Thermal Stabilization of Pb2+ and Cu2+ by Zeolite

Xingwen Lu,Fei Wang,Xiao-yan Li,Kaimin Shih,Eddy Y. Zeng

In recent years, zeolite has been proven to be a cost-effective adsorbent for treating wastewater containing heavy metal ions. However, few studies have investigated the subsequent treatment of metal-laden zeolites after adsorption, which may become a source of secondary pollution if not properly dealt with. To fill the knowledge gap, the adsorption behavior of Pb2+ and Cu2+ on zeolite was examined in the present study. The adsorption process was fast and reached equilibrium within 60 min, with adsorption data fitted better with the Langmuir equation than the Freundlich equation. After thermal treatment for metal-adsorbed zeolites, X-ray diffraction results showed that Pb2+ and Cu2+ adsorbed on zeolites can be readily stabilized into PbAl2Si2O8 and CuAl2O4, and the best temperatures for formation of PbAl2Si2O8 and CuAl2O4 were 950 and 1000 °C, respectively. Finally, a prolonged leaching test (at pH 2.9 for 22 d) demonstrated that the Pb2+ and Cu2+ concentrations in the leachate of calcined samples were approximately 2 orders of magnitude lower than those of untreated samples, validating the high stability of treated zeolites. All these findings pointed to the potential for use of zeolites as a promising and sustainable strategy to treat and stabilize Pb2+ and Cu2+ in wastewater.

Hybrid Electrochemical-Surface Plasmon Resonance Microfiber Sensor for Pb2+ Detection

Xiaoling Peng,Zhicong Ren,Changhai Lu,Penglai Guo,Weicheng Chen,Daotong You,Kaiwei Li,Tuan Guo,Gaozhi Xiao,Jianqing Li

Magnetic mesoporous silica/ε-polylysine nanomotor-based removers of blood Pb2+

Zhiyong Liu,Tingting Xu,Meng Wang,Chun Mao,Bo Chi

The removal of excessive blood lead ions (Pb2+) is very important to human health, but current effective removal technology is still lacking because of the complex existence state of Pb2+ in blood, which can be attributed to the fact that most of the blood Pb2+ is combined with haemoglobin (Hb) located in red blood cells (RBCs). Here, a new type of magnetic mesoporous silica/ε-polylysine nanomotor-based remover (MMS/P NR) with abundant chelation sites was designed, synthesized and used to remove Pb2+ from blood. The magnetic core can make the nanocomposites become nanomotors with autonomous movement under an external variable magnetic field, which can effectively improve the contact probability between the MMS/P NRs and Pb2+-contaminated Hb in RBCs. The amino rich ε-polylysine (ε-PL) was used as the co-template of mesoporous silica. Mesoporous channels can provide a confinement effect for Pb2+-contaminated Hb to stabilize the captured blood Pb2+. The movement behavior of the MMS/P NRs in and out of RBCs and the capture mechanism of Pb2+ in the blood were studied. The results indicate that the MMS/P NRs we propose have good blood compatibility, low cytotoxicity, magnetic properties, autonomous movement ability and recyclability under the condition of an external magnetic field. Moreover, compared with the experimental conditions without an external variable magnetic field (0.01485 mg g−1), the MMS/P NRs show a higher blood Pb2+ removal ability under the condition of an external variable magnetic field (0.05525 mg g−1). The design strategy of this remover based on nanomotor technology has great potential in the future medical treatment of heavy metal poisoning.

Pb2+-Doping-Activated Localized Luminescence of Organic-Inorganic Cobalt (II) Bromides

Jiali Fu,Tongzhou Li,Quan Zhao,Xiaodong Shen,Qingyi Huang,Tao Huang,Bingsuo Zou

Transition-metal Co2+ions in halide systems are generally regarded as inefficient emitters due to rapid nonradiative relaxation of their d-d excited states. Here, we prepared two zero-dimensional (0D) organic-inorganic hybrid cobalt halides, benzyl triphenyl phosphonium bromide cobalt ((BTP)2CoBr4) and triphenyl phosphonium bromide cobalt ((PPh3)2CoBr4), composed of [CoBr4]2−tetrahedra embedded in distinct organic frameworks. Upon Pb2+incorporation, both compounds exhibit visible photoluminescence composed mainly of two emission bands centered at approximately 450 and 500 nm, with decay lifetimes on the nanosecond timescale. The emission at 450 nm originates from d-d transitions associated with short-range Co-Co ferromagnetic (FM) interactions, whereas the 500 nm emission can be attributed to donor-acceptor pair (DAP) transitions involving Co and Pb. At low temperatures, an additional broadband emission centered at ~620 nm emerges in Pb2+-doped (PPh3)2CoBr4, with lifetimes reaching the microsecond scale, while such emission is not observed in (BTP)2CoBr4. Low-temperature lattice contraction in the PPh3framework further shortens the Co-Co distance, thereby enhancing short-range FM interactions and leading to the formation of a magnetic bipolaron for emission. Overall, this work reveals the role of organic ligand structure and dopant modulation in regulating the Co-centered excited states, providing deeper insight into the interactions between cobalt ions and organic ligands in low-dimensional halide systems.

Induced crystallization of Pb2+ on smithsonite surface during sulfidation-xanthate flotation

Rongdong Deng,Yi Wang,Wenting Duan,Dingquan Xing,Yuan Hu

Smithsonite is a common oxidized zinc ore , and its recovery has gained increasing attention to meet the high demand for zinc. Current methods to concentrate oxidized zinc ores are through sulfidation flotation or “sulfidation + metal + xanthate” flotation. However, such techniques are not sufficiently efficient for treating smithsonite. In this study, Pb(NO 3 ) 2 was used to pre-treat smithsonite as a crystallization inducer, and the mechanism of lead modification was studied through micro-flotation tests, adsorption measurements, contact angle measurements, X-ray diffraction (XRD), scanning electronic microscopy (SEM), and TOF-SIMS analysis. The micro-flotation test results showed that the recovery of smithsonite after Pb 2+ pre-treatment increased from 80.3% to 85.3%. The comprehensive results of adsorption experiments, contact angle measurements, XRD and SEM analysis indicated that Pb 2+ adsorbed on the smithsonite surface and transformed portion of smithsonite into cerussite, increasing the active sites on the mineral surface for adsorption of S ions . The newly formed PbS after sulfidation had an effect of induced crystallization on subsequently formed PbS, increasing PbS species and making the surface more effective for xanthate flotation. ToF-SIMS was used to visualize the 3D distribution of Pb 2+ and S 2- adsorption, and it further proved that pre-treatment with Pb(NO 3 ) 2 enhanced the sulfidation process of smithsonite.

Stable Pb2+ ion-selective electrodes based on polyaniline-TiO2 solid contacts

Xianghua Zeng,Wenen Jiang,Xiaohui Jiang,Geoffrey I.N. Waterhouse,Zhiming Zhang,Liangmin Yu

A novel Pb 2+ ion selective electrode based on a polyaniline-doped titanium dioxide (PANI-TiO 2 ) solid contact, denoted herein as GC/PANI-TiO 2 /Pb 2+ -ISE, was successfully developed. The GC/PANI-TiO 2 /Pb 2+ -ISE exhibited a stable and rapid potential response to Pb 2+ ions, with a linear response over the concentration range 10 −3 -10 −9  M, a detection limit of ∼10 −9.1  M and a response time of only 10–15 s. The PANI-TiO 2 solid contact layer possessed a large specific capacitance , thereby effectively promoting ion-to-electron transduction and enhancing the output stability (potential drift, 122.6 μV/s). The developed electrode maintained excellent performance during continuous use, showing a linear response range of 10 −3 -10 −7  M with no obvious changes in the potential response time or response slope (29 ± 0.2 mV/decade) over six weeks. Results encourage the wider use of conducting polymer-semiconductor solid contacts in ion selective electrode development.

In situ polymerized poly(acrylic acid)/alumina nanocomposites for Pb2+ adsorption

Ya-Ping Wang,Peng Zhou,Shi-Zhong Luo,Sijie Guo,Jing Lin,Qian Shao,Xingkui Guo,Zhongqing Liu,Jun Shen,Bin Wang,Zhanhu Guo

In this study, two poly(acrylic acid)/alumina (PAA/alumina) nanocomposites with varied polymer loadings were prepared via in situ polymerization of preadsorbed acrylic acid. One composite would have a ~1/4-monolayer polymer coverage, while the other had a ~2-monolayer coverage. The produced composite materials were characterized in the adsorptive behavior of Pb 2+ from aqueous solution. When there was less PAA produced in a nanocomposite sample, there was higher Pb 2+ sorption capacity due to potentially less blocked alumina pores by in situ formed PAA. Isothermal and kinetic models for Pb 2+ sorption were applied by considering the effects of the initial Pb 2+ concentration and the contact time. The adsorption kinetics was best expressed using the pseudo-second-order equation. Through the isothermal studies, the maximum Pb 2+ monolayer adsorption capacity of 167.79 mg/g was recorded for the composite with higher PAA loading.

Pb2+ Responsive Cu-In-Zn-S Quantum Dots With Low Cytotoxicity

Han XiaoLe,Yu Fan,Lei JiaWen,Zhu Jiahua,Fu HaiYan,Hu JunCheng,Yang Xiao-Long

Water-soluble Cu-In-Zn-S quantum dots (CIZS QDs) with orange fluorescence have been synthesized with a glutathione (GSH) as stabilizer via facile a one-step hydrothermal method. The optimal reaction conditions of CIZS QDs including temperature, time, pH, and the molar ratios of precursors were studied. TEM results indicate that the aqueous-dispersible CIZS QDs are quasi-spherical, and the average diameters are 3.76 nm with excellent fluorescent stability. Furthermore, the cytotoxicity of CIZS QDs was investigated by the microcalorimetry combining with TEM and the IC50 was 10.2 μM. CIZS QDs showed a promising perspective in applications such as a fluorescent probe for bioimaging and biolabeling due to the low cytotoxicity and good biocompatibility. Moreover, the CIZS QDs can distinguish Pb2+ ion from other ions, offering great potentials in lead ion determination in drinking water. According to the results of UV, XRD, FL, PL, and ITC methods, the mechanism of CIZS QDs-Pb2+ assay is due to hydrogen bonding or van der Waals forces in the formation of Pb2+ and CIZS QDs.

Ultrabright carbon dots as a fluorescent nano sensor for Pb2+ detection

Xiang Long,Ruixue Li,Jiamei Xiang,Shaogui Wu,Jiayang Wang

In this work, we synthesized ultrabright carbon dots (U-CDs) with photoluminescence quantum yield (PLQY) up to ∼100% using CA and EDA as precursors. When studying their interaction with the Pb2+ ion, we found that the PL quenching degree is independent of the U-CDs concentration. This feature provides great convenience for practical detection, which allows the standard curve determination and practical detection to be conducted under different U-CDs concentrations with detection error less than 20%. Based on the experimental observations, a possible mechanism is proposed to explain this phenomenon. To our best knowledge, this work has never been reported before and provides a new idea for the design of novel fluorescent sensors.