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[Display omitted] • Pd/PANI-rGO catalyst was prepared by in-situ redox reaction. • Lamellar PANI-modified rGO offers abundant attachment sites for Pd. • Pd/PANI-rGO exhibits superior electrocatalytic properties for EGOR and EOR. • The theoretical reference for PANI used as anode catalyst support was provided. Design and preparation of catalysts with lower cost and higher catalytic efficiency are still important strategy to promote the wide application of alkaline direct alcohol fuel cells (ADAFCs). In this study, a novel anode catalyst for ADAFCs has been easily synthesized based on polyaniline (PANI)-modified wrinkled reduced graphene oxide (rGO) and Pd nanoparticles (Pd NPs). Morphology and structure characterization confirm the modified lamellar structure and composition of the Pd/PANI-rGO composite, and X-ray photoelectron spectroscopy (XPS) demonstrates the electron transfer from PANI-rGO to Pd NPs. For ethylene glycol and ethanol oxidation reactions (EGOR/EOR) in alkaline media, the Pd/PANI-rGO exhibits promising electrocatalytic properties with mass activity as 4342.5 and 2220.4 mA mg Pd -1, specific activity as 26.6 and 13.6 mA cm-2 and intrinsic activity as 5.7 and 2.5 s-1, respectively. Moreover, the Pd/PANI-rGO shows significantly enhanced anti-poisoning ability and durability as compared with contrast samples due to the well dispersion of Pd NPs on PANI-rGO and the synergistic interaction between PANI-rGO and Pd NPs producing electron-rich Pd and more active sites for EGOR and EOR. This work is expected to provide theoretical foundation for designing low-cost and high-efficiency ADAFCs anode catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel sunset yellow sensor is fabricated with MWCNT-CONH-66-UiO/PEDOT:PSS composites. • The amidation reaction of UiO-66-NH 2 converts –NH 2 into –NHCO- for protection. • This sensor performs a linear range as 0.01–70 μM and a LOD as 3.3 nM. • The sensor is successfully applied to sunset yellow detection in cake and meat. The out-of-range, overdose and illegal usage of sunset yellow azo dye in food will cause great damage to food safety and consumer health. In this work, a novel electrochemical sensing platform toward sunset yellow detection was prepared based on the amidated MWCNT-CONH-66-UiO and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). In MWCNT-CONH-66-UiO, the –NHCO- is produced by the amidation reaction between zirconium 2-amino terephthalate (UiO-66-NH 2) and carbonylated multi-walled carbon nanotubes (MWCNT-COOH), which play significant role for the enhancement of the sensing properties of MWCNT-CONH-66-UiO/PEDOT:PSS composite. PEDOT:PSS acts as a conducting film coated on MWCNT-CONH-66-UiO and alleviates the electrooxidation of –NHCO-. The large specific surface area, good conductivity, and outstanding synergistic effect of the composite trigger off prominent sensing properties of MWCNT-CONH-66-UiO/PEDOT:PSS toward sunset yellow detection with the lowest detection limit as 3.3 nM and a sensitivity as 6.6 mA mM−1 cm−2 (active area of 0.15 cm2). Additionally, this sensor shows satisfactory results for sunset yellow detection in plain cake and marinating meat via DPV in comparison to the high-performance liquid chromatography method. The research results in this work will provide technical support for the rapid and efficient detection of azo dyes in food, animal feeds, and industrial wastewater. [ABSTRACT FROM AUTHOR]

A novel molecularly imprinted sensor was developed for the voltammetric determination of adrenaline (AD). MXene/carbon nanohorn (MXene/CNH) composite with good electric conductivity and enormous accessible active sites was firstly introduced as catalytic substrate. Subsequently, molecularly imprinted polymer (MIP) film was fabricated in mixed solutions containing hydroxymethyl-3,4-ethylenedioxythiophene (functional monomer) and AD (template) through electro-polymerization process. A molecularly imprinted sensor was formed after removing the template. The morphology and elemental composition of the prepared composites were studied by scanning electron microscopy and X-ray photoelectron spectroscopy. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were used to investigate the electrochemical performance of the molecularly imprinted sensors. Under optimized conditions, the designed sensor displays a wide linear range from 1.0 nM to 60.0 μM and a low limit of detection of 0.3 nM. The developed sensor also presents good selectivity, reproducibility and long-term stability, and satisfactory feasibility in practical sample analysis. MXene/carbon nanohorns decorated with conductive molecularly imprinted poly(hydroxymethyl-3,4-ethylenedioxythiophene) was proposed for highly sensitive and selective detection of adrenaline. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanozyme sensor comprised of electro-synthesized imprinted PEDOT with graphene-like MoS 2 was prepared. • Imprinted nanozyme was employed for detection of luteolin with good electrochemical sensing performance. • The proposed method electrochemically detected luteolin in Gnaphalium affine obtained acceptable recoveries. A novel nanozyme sensor based on the electro-synthesized molecularly imprinted conducting poly(3,4-ethylenedioxythiophene) (PEDOT) nanocomposite with graphene-like two-dimensional layered molybdenum disulfide (MoS 2) was successfully prepared for electrochemical detection and analysis of luteolin in Gnaphalium affine. MoS 2 -MIPs were prepared facilely by electrochemical polymerization of monomer 3,4-ethylenedioxythiophene in the presence of both modifier MoS 2 and template molecule luteolin that can change the morphological structure and specific surface area of PEDOT, enhance electronic conductivity of MoS 2 , and improve the recognition capability and electrocatalytic capacity of electrode interface. The morphological structure of MoS 2 -MIPs was characterized by SEM, and its electrochemical performance and sensing parameters were investigated by voltammetry. The electrochemical response of luteolin was recorded by MoS 2 -MIPs in the linear concentration range from 3 × 10-7 to 3 × 10-5 Μ with limit of detection of 0.04 μΜ under the optimal conditions, which was successfully employed for electrochemically detecting luteolin in Gnaphalium affine with acceptable recoveries in comparison with high-performance liquid chromatography. This will provide a new nanozyme sensing platform comprised of electro-synthesized molecularly imprinted conducting polymers and graphene-like two-dimensional layered nanomaterials. [ABSTRACT FROM AUTHOR]

Infections caused by Staphylococcus aureus (S. aureus) are increasing difficult to treat because this pathogen is easily resistant to antibiotics. However, the development of novel antibacterial agents with high antimicrobial activity and low frequency of resistance remains a huge challenge. Here, building on the coupling strategy, an adamantane moiety was linked to the membrane-active Ru-based structure and then developed three novel metalloantibiotics: [Ru(bpy) 2 (L)](PF 6) 2 (Ru1) (bpy = 2,2-bipyridine, L = amantadine modified ligand), [Ru(dmb) 2 (L)](PF 6) 2 (Ru2) (dmb = 4,4′-dimethyl-2,2′-bipyridine) and [Ru(dpa) 2 (L)](PF 6) 2 (Ru3), (dpa = 2,2′-dipyridylamine). Notably, complex Ru1 was identified to be the best candidate agent, showing greater efficacy against S. aureus than most of clinical antibiotics and low resistance frequencies. Mechanism studies demonstrated that Ru1 could not only increase the permeability of bacterial cell membrane and then caused the leakage of bacterial contents, but also promoted the production of reactive oxygen species (ROS) in bacteria. Importantly, complex Ru1 inhibited the biofilm formation, exotoxin secretion and increased the potency of some clinical used antibiotics. In addition, Ru1 showed low toxic in vivo and excellent anti-infective efficacy in two animal infection model. Thus, Ru-based metalloantibiotic bearing adamantane moiety are promising antibacterial agents, providing a certain research basis for the future antibiotics research. [Display omitted] • An adamantane moiety was linked to Ru-based structure and then developed three novel metalloantibiotics. • Complex Ru1 showed excellent antibacterial activity against S. aureus , a stronger potency than most of clinical antibiotics and most of antibacterial Ru-based agents we reported before, and low resistance frequencies. • Complex Ru1 could not only destroy the bacterial cell membrane, but also promote production of ROS in bacteria. • Ru1 has low toxicity and exhibited robust anti-infective efficacy in vivo , better than vancomycin. [ABSTRACT FROM AUTHOR]

There is clearly a need for the development of new classes of antimicrobials to fight against multidrug-resistant bacteria. Here, we designed and synthesized of three ruthenium polypyridyl complexes: [Ru(bpy)2(BTPIP)](ClO4)2 (Ru(II)-1), [Ru(bpy)2(ETPIP)](ClO4)2 (Ru(II)-2) and [Ru(bpy)2(CAPIP)](ClO4)2 (Ru(II)-3) (N-N = bpy = 2,2′-bipyridine), their antimicrobial activities against S. aureus were assessed. The lead complexes of this set, Ru(II)-1(MIC = 0.016 mg/mL), was tested against biofilm. We also investigated whether bacteria can easily develop resistance to Ru(II)-1. The result demonstrated that S. aureus could not easily develop resistance to the ruthenium complexes. In addition, aimed to test whether ruthenium complexes treatment could increase the susceptibility of S. aureus to antibiotics, the synergism between Ru(II)-1 and common antibiotics against S. aureus were investigated using the checkerboard method. Interesting, Ru(II)-1 could increased the susceptibility of S. aureus to some aminoglycoside antibiotics(kanamycin and gentamicin). Finally, in vivo bacterial infection treatment studies were also conducted through murine skin infection model. These results confirmed ruthenium complexes have good antimicrobial activity in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a readily available copolymer that comes as an aqueous dispersion with good processability. A flexible voltammetric sensor for the widely used food stabilizer tert.-butylhydroquinone (TBHQ) was constructed by using a film of PEDOT:PSS. The electron transfer efficiency of the electrode was enhanced by doping with dimethyl sulfoxide (DMSO), and mass transport at the electrode-electrolyte interface was increased by adding the cationic surfactant cetyltrimethylammonium bromide (CTAB) which acts as a sorbent for TBHQ. SEM, AFM, XPS, UV − vis and electrochemical analysis were conducted to characterize the properties of the electrode. After optimization of the experimental conditions, the electrode operated at a working potential of 0.17 V (vs. SCE) has a linear response in the 0.5–200 μM TBHQ concentration range and a lower detection limit of 0.15 μM (at S/N = 3). It was applied for the determination of TBHQ in spiked real samples, and recoveries ranged between 96.85 and 103.41%. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus (S. aureus), one of the Gram-positive bacteria, is easily to develop drug-resistance. Drug-resistant S. aureus infection leads to high morbidity and mortality. The complexes, namely [Ru(dpa) 2 (PSPIP)](PF 6) 2 (Ru1), [Ru(dpa) 2 (TSPIP)](PF 6) 2 (Ru2), and [Ru(dpa) 2 (TBPIP)](PF 6) 2 (Ru3), were synthesized using 2, 2′-dipyridylamine as an auxiliary ligand and three main ligands PSPIP, TSPIP, TBPIP. In vitro studies demonstrated that the Ru1–3 exhibited excellent antibacterial activity against S. aureus while showing low hemolytic toxicity to rabbit red blood cells. Notably, Ru3 was found to disrupt the bacterial cell membrane and alter its permeability through fluorescence staining and scanning electron microscopy (SEM) analysis. Furthermore, Ru3 displayed low toxicity in G. mellonella Larvae. Ru3 exhibited good activity against S. aureus in G. mellonella Larvae infection model and mouse skin infection model.To some extent, Ru3 inhibited biofilm formation on S. aureus as well as hemolytic toxin production, thereby attenuating the development of drug resistance without cross-resistance with other antibiotics. In addition, complex Ru3 exhibited a synergistic effect when combined with antibiotics amikacin, kanamycin, tobramycin and chloramphenicol, making it a valuable antibiotics adjuvant. [Display omitted] • Ru3 was found to inhibit biofilm formation of S. aureus. • Ru3 plays an antibacterial role by destroying bacterial cell membranes. • Ru3 was found to prevent S. aureus from developing drug resistance and reduce the risk of cross-resistance. [ABSTRACT FROM AUTHOR]

Abstract In this work, electrode based on poly(3,4-ethylenedioxythiophene) (PEDOT) was employed for the fabrication of an efficient sensor for 4-chloro-3-methylphenol (PCMC) detection. To improve the dispersity and increase the specific surface area of PEDOT, core-shell structured UiO-66-NH 2 @PEDOT was designed by in-situ oxidation method using Zr-based metal-organic framework (UiO-66-NH 2) as template. In addition, to achieve a further increased active surface area and electron transfer rate of the modified materials, graphene aerogel (GA) was utilized as substrate material for the assembly of UiO-66-NH 2 @PEDOT. Then, the obtained UiO-66-NH 2 @ PEDOT/GA modified electrode was employed as an electrochemical sensor for PCMC detection. Experiment parameters, such as pH value of acetate buffer solution and accumulation time, were optimized in detail. Under the optimized experiment condition, the UiO-66-NH 2 @PEDOT/GA electrode showed a good linear range of 0.6–18 μM, as well as a low detection limit of 0.2 μM (S/N = 3). The UiO-66-NH 2 @PEDOT/GA electrode was applied toward the detection of PCMC in tap water with good recovery. All these features suggest that the prepared PEDOT-based composite could serve as a promising sensing platform for monitoring water pollutants. Graphical abstract 3D UiO-66-NH 2 @PEDOT/GA modified electrode as an electrochemical sensor was employed for 4-chloro-3-methylphenol detection. Unlabelled Image Highlights • A novel 3D UiO-66-NH 2 @PEDOT/GA composite was obtained through facial approach. • UiO-66-NH 2 @PEDOT/GA electrode was applied for the electrochemical detection of PCMC. • Low detection limit and wide linear range for PCMC were obtained. • The method can detect PCMC in tap water with good recovery. [ABSTRACT FROM AUTHOR]

Abstract Three new platinum(II) complexes with pendent morpholine were synthesized, namely complex 1 ([Pt(L)Cl]CF 3 SO 3), complex 2 ([Pt(L)(NH 3)](CF 3 SO 3) 2) and complex 3 ([Pt(L)(PPh 3)](CF 3 SO 3) 2), where L = 4′-[4-(4-morpholinobutyloxy)phenyl]-2,2′:6′,2″-terpyridine and PPh 3 = triphenylphosphine. The detailed molecular structures of complex 3 , L and its precursor L′ (1,4′-[4-(4-bromobutyloxy)phenyl]-2,2′:6′,2″-terpyridine) were determined by single crystal X-ray diffraction. An evaluation of in vitro cytotoxicity for both ligand and complexes was performed by methyl thiazolyl tetrazolium (MTT) assay in three cancer cell lines and normal cells as the control, respectively. IC 50 values of complexes 1 – 3 were lower than those exhibited for the reference drug cisplatin, and selectivity of these complexes were greater than cisplatin. Among them, complex 3 with a leaving group PPh 3 was found to be the most efficacious complex against certain cell lines, especially for cisplatin-resistant A549cisR cells. These complexes were found to bind DNA, induce efficient DNA unwinding. Meanwhile, topoisomerase (Topo) I inhibitory activities by three complexes were detected, and a minimum inhibitory concentration of 15 μM of complex 3 was found totally inhibit Topo I activity. Graphical abstract Three new platinum(II) complexes were synthesized and characterized. Those complexes can displace ethidium bromide (EB) from the DNA-EB conjugation and exhibit high DNA binding affinities. Complex 3 {([Pt(L)(PPh 3)](CF 3 SO 3) 2), L = 4′-[4-(4-morpholinobutyloxy)phenyl]-2,2′:6′,2″-terpyridine}, exhibits the best topoisomerase I inhibitory activity and significant anticancer activity. Unlabelled Image Highlights • Three new anticancer Pt(II) complexes have been synthesized and characterized. • These complexes exhibit interesting topoisomerase I inhibitory and antitumor activities. • The substituent effects of functional groups on cytotoxic potency were significant. [ABSTRACT FROM AUTHOR]

Abstract Two novel chiral 3,4-dihydro-2 H -thieno[3,4- b ][1,4]dioxepine (ProDOT)-based electrochemical sensor, employing a pair of glassy carbon electrodes modified with chiral poly(2-Phenyl-propionic acid 3,4-dihydro-2 H -thieno[3,4- b ][1,4]dioxepin-3-ylmethyl ester) (PProDTM-PP), were utilized for the enantioselective detection of chiral 3,4-dihydroxyphenylalanine (DOPA). The enantioselective recognition between chiral PProDTM-PP modified glassy carbon electrodes and chiral DOPA was studied by using different electrochemical technologies. The redox activity and electrochemical stability of chiral PProDTM-PP was good. (R)-PProDTM-PP and (S)-PProDTM-PP showed higher peak current responses toward D -DOPA and L -DOPA, respectively. Furthermore, the recognition efficiencies of chiral PProDTM-PP are between 1.48 and 1.89, which is higher than chiral PEDOT-based electrochemical sensors (around 1.10). The chiral PProDTM-PP provides an alternative to chiral recognition. [ABSTRACT FROM AUTHOR]

• Electrochemical sensing platforms were fabricated based on MOF-doped Au/PEDOT composites. • The electronic effects between Au/PEDOT and MOF dopants play significant role in improving the catalytic activity of the composites. • Both the Au/PEDOT/ZIF-8 and Au/PEDOT/MWCNT-CONH-UIO-66 composites perform satisfactory sensing properties toward CA and SY simultaneous detection. • Simultaneously detecting CA and SY in tea beverage electrochemically for the first time. Herein, the electrochemical sensing platform has been proposed based on metal-organic framework doped Au/poly(3,4-ethylenedioxythiophene) (PEDOT) composites to simultaneously detect the catechin and sunset yellow in tea beverage. The characterization reveals that the Au nanoparticles distribute well on/in conducting PEDOT, and the relatively few UIO-66 particles as the dopant intersperse the Au/PEDOT composites. The electrochemical test has been used to study the sensing properties toward catechin and sunset yellow simultaneous detection. The results show that the Au/PEDOT/MWCNT-CONH-UIO-66 performs a wide range of 0.03∼60 µM and 0.3∼40 µM, low detection limit as 0.01 μM / 0.15 μM towards catechin and sunset yellow simultaneous detection, respectively. Furthermore, the Au/PEDOT/MWCNT-CONH-UIO-66 possesses a wide linear detection range and high sensitivity for catechin and sunset yellow detection. Moreover, the Au/PEDOT/MWCNT-CONH-UIO-66 composite also has great stability and anti-interference ability. Finally, the sensing platform was applied to detect catechin and sunset yellow in the tea beverage compared with the high-performance liquid chromatography method. To the best of our knowledge, our work first reported the electrochemical sensing materials for catechin and sunset yellow simultaneous detection in food, which will provide a certain theoretical analysis and experimental experience for the preparation of materials used for catechin and sunset yellow simultaneous detection in food. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanowire poly (3,4-dihydro-2 H -thieno [3,4- b ] [1,4]dioxepin-3-yl)methanol (PProDTM) free-supporting films with conductivities around 1.92 S cm −1 were prepared using a template-free electropolymerization method. The structure, morphology, mechanical properties, and thermal stability of the PProDTM films were characterized by Fourier transform infrared spectroscopy, UV–vis spectroscopy, scanning electron microscopy, dynamic mechanical analysis and thermogravimetric analysis. Moreover, the capacitance performances of PProDTM films were investigated in aqueous and organic electrolytes (acetonitrile (ACN) and dichloromethane (DCM)). In 0.1 M H 2 SO 4 , a symmetrical supercapacitor based on PProDTM exhibited specific capacitance of 89.2 F g −1 at a current density of 1.0 A g −1 , an energy density of 3.1 Wh kg −1 at power density of 0.5 kW kg −1 and the cycling capacitance retention was 74.8% after 5000 cycles. As the scan rate and current density increased, the specific capacitance of PProDTM films clearly decreased in DCM, but no obvious changes occurred in water and ACN. In ACN containing 0.1 M Bu 4 NBF 4 , a symmetrical supercapacitor based on PProDTM exhibited specific capacitance of 99.6 F g −1 at a current density of 1.0 A g −1 , an energy density of 3.5 Wh kg −1 at power density of 0.5 kW kg −1 and the cycling capacitance retention was 82.2% after 5000 cycles. These results imply that our flexible free-supporting PProDTM films are promising for future use in supercapacitors. [ABSTRACT FROM AUTHOR]

A sensitive Pb(II) sensor was fabricated based on Co 3 O 4 /reduced graphene oxide/chitosan (Co 3 O 4 /rGO/chitosan) nanocomposite modified glassy carbon electrode (GCE). The Co 3 O 4 /rGO material was synthesized through in situ growth of Co 3 O 4 nanoparticles (NPs) on GO and subsequent hydrazine reduction process. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that Co 3 O 4 NPs with a diameter of around 100 nm are attached on rGO sheets. The structures and compositions of Co 3 O 4 /rGO were further characterized by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Many experimental parameters, such as pH value, deposition time and deposition potential were optimized. Under optimal conditions, the calibration plot for Pb(II), with data acquired at − 0.556 V ( vs . SCE) is linear in the concentration range from 1.0 to 200.0 nM. Combining the good conductivity and high surface area of rGO, strong Pb(II) adsorption ability of Co 3 O 4 NPs, and excellent Pb(II) complex-forming ability of chitosan, the nanocompsite provides a sensitive Pb(II) senor with a detection limit of 0.35 nM. Moreover, the positively charged chitosan can interact with the negatively charged rGO to increase the stability of Co 3 O 4 /rGO nanocomposite. The hybrid nanocomposite Pb(II) senor provides new opportunity for vegetable analysis. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) dotted S-doped carbon (AuNPs/S-C) nanoflakes were synthesized via a facial and simple approach. Typical synthesis route involves the formation of gold nanoparticles/poly(3,4-ethylenedioxythiophene) (AuNPs/PEDOT) and a subsequent calcination process. Many techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) were used to characterize their morphology, structures and compositions. Results indicated that AuNPs with an average size of 5 nm were uniformly dotted on/into the S-C nanoflakes. The AuNPs/S-C/nafion was utilized as a new electrode material for simultaneously electrochemical determination of Cu (II) and Hg (II) using differential pulse anodic stripping voltammetry (DPASV) technique. Benefiting from the efficient metal-complexing ability and electrocatalytic activity of S-C and the good conductivity of AuNPs, the modified electrode exhibited enhanced electrochemical performance compared with bare glassy carbon electrode. Under optimal conditions, the peak currents displayed linear response to the concentrations of Cu (II) and Hg (II) ranges from 0.64 to 63.55 μg/L and 4.01 to 300.89 μg/L, with detection limits of 0.19 μg/L and 1.40 μg/L (S/N = 3), respectively. The modified electrode was also applied for the determination of Cu (II) and Hg (II) in lake water samples with good results. [ABSTRACT FROM AUTHOR]

Free-standing conductive films are important for the application in organic electronics. However, PEDOT as one of the most promising CPs is difficult to be prepared into free-standing paper. Herein, a novel EDOT derivative, 1,6-bis((2,3-dihydrothieno[3,4- b ][1,4]dioxin-2-yl)methoxy)hexane (BEDTH), was synthesized and easily electrodeposited into free-standing flexible conducting poly(1,6-bis((2,3-dihydrothieno[3,4- b ][1,4]dioxin-2-yl)methoxy)hexane) (PBEDTH) in CH 2 Cl 2 containing 0.1 M Bu 4 NBF 4 . The free-standing PBEDTH films with the conductivity of 0.11 S cm −1 were characterized by FT-IR, UV–vis, SEM, TG, dynamic mechanical analysis and electrochemical method, respectively. Electrochemical results indicated that the specific capacitance of PBEDTH film was 40.8 F g −1 at the current density of 0.5 A g −1 in ionic liquid BmimBF 4 with the cycling capacitance retention of 86.7% after 5000 cycles. Additionally, the thermoelectric property of free-standing flexible PBEDTH film was also studied, showing the Seebeck coefficient was 37.2 μV K −1 and the power factor was 0.015 μW K −2 m −1 at 300 K. Although the capacitive and thermoelectric performance is not satisfactory, the free-standing flexible PBEDTH films will still be promising in the areas of energies and sensors in the true sense. [ABSTRACT FROM AUTHOR]

Herein, an electrochemical sensor was developed for detecting heavy metal ions by using a carboimidazole grafted reduced graphene oxide (reduced graphene oxide-NH-carboimidazole, abbreviated as RGO-NH-Ci) modified electrode. The morphology of RGO-NH-Ci material was characterized by scanning electron microscopy (SEM). The electrochemical behaviors of the RGO-NH-Ci modified electrode toward heavy metal ions, including Hg 2 + and Pb 2 + , were investigated with differential pulse anodic stripping voltammetry (DPASV). Compared with pure reduced graphene oxide (RGO), RGO-NH-Ci modified electrode showed improved analytical performance in detecting the two metal ions owing to the strong complexing capacity of Ci and the presence of the amino groups. The detection limits were estimated to be 0.2 nM and 3.0 nM for Hg 2 + and Pb 2 + , respectively, under the optimized conditions. The developed method was also employed to detect the Hg 2 + and Pb 2 + in real water samples, and satisfactory results were obtained. [ABSTRACT FROM AUTHOR]

The derivative of terthiophene oligomer 2-(2,5-di(thiophen-2-yl)thiophen-3-yl)acetic acid (TTAA) was synthesized, and its electropolymerization was researched comparatively by using three systems (CH 3 CN-Bu 4 NPF 6 , CH 2 Cl 2 -Bu 4 NPF 6 , and BFEE). The effects of solvent on the electrochemical, morphology, redox stability, spectroelectrochemical properties and electrochromic performance of the achieved poly(2-(2,5-di(thiophen-2-yl)thiophen-3-yl)acetic acid) (PTTAA) films were studied in detail. PTTAA could be electrosynthesized in all the three systems facilely and displayed wonderful electroactivity and prominent redox stability in a wide potential window. The PTTAA films obtained in CH 3 CN-Bu 4 NPF 6 and CH 2 Cl 2 -Bu 4 NPF 6 had similar electrochemistry property except morphology. PTTAA formed in BFEE had lower oxidation potential (0.4 V) and better cycling stability. Also, it showed moderate response time (1.2 s) and excellent coloration efficiency (391 cm 2 C −1 ), enhanced its possible application as electrochromic material. So compared with common solvents CH 3 CN and CH 2 Cl 2 , TTAA could electrochemical polymerization at a lower potential and got higher quality polymer films in the strong Lewis acid BFEE. And this also made PTTAA as-formed in BFEE had better redox stability and electrochromic perfromance. [ABSTRACT FROM AUTHOR]

Abstracts Development of selective methods for the detection of mercury (Hg 2+ ) has received tremendous attention in modern chemical research due to its health hazard and persistence in environment. In this paper, the electrochemical determination of Hg 2+ at trace level based on poly(3,4-ethylenedioxythiophene) nanorods/graphene oxide nanocomposite modified glassy carbon electrode (PEDOT/GO/GCE) is reported. PEDOT/GO nanocomposite has been proposed via a simple liquid–liquid interfacial polymerization approach. Scanning electron microscopy (SEM) and transmission electron microscope (TEM) were employed to characterize the morphology and structure of the as-prepared PEDOT/GO. The results revealed that PEDOT with a nanorods-like structure anchored on the surface of GO nanosheets, which could enhance the electro-active sites of the nanocomposite. Differential pulse stripping voltammetry (DPSV) was applied to determine low concentrations of Hg 2+ on PEDOT/GO/GCE. Experimental conditions, including accumulation time, pH values and deposition potential were optimized. In optimal conditions, a good linear relationship was found between peak currents and the concentration of Hg 2+ in 10.0 nM-3.0 μM range. The detection limit was estimated to be 2.78 nM at a signal-to-noise ratio of 3. Finally, the applicability for Hg 2+ determination in tap water samples was successfully demonstrated. [ABSTRACT FROM AUTHOR]

Large-scale chloromethyl functionalized poly(3,4-ethylenedioxythiophene) nanowires (PEDOT-MeCl), poly(2-chloromethyl-2,3-dihydrothieno[3,4- b ][1,4]dioxine), were easily electrodeposited in acetonitrile solution containing 0.1 M lithium perchlorate without any templates. The PEDOT-MeCl nanowires were characterized by FT-IR, TG, SEM, TEM and electrochemical technologies. The nanowires structural PEDOT-MeCl with diameter of about 20 nm displayed good thermal stability and high specific capacitance of 174 F g −1 at 25 mV s −1 . Furthermore, the energy density of the symmetric supercapacitor built by PEDOT-MeCl nanowires reached 6.95 Wh kg −1 at a power density of 1625 W kg −1 , and the specific capacitance retention was 81% after 1000 cycles. The above information implied the bright prospect of the PEDOT-MeCl nanowires as electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

The polyether-bridged 2,2′-bithiophenes were designed with a single methylene between the thiophene ring and the first oxygen atom in polyether, and synthesized by the Williamson reaction and the Suzuki coupling reaction. The electrochemical polymerization of as-synthesized monomers were investigated. The as-prepared polymers of polyether-bridged 2,2′-bithiophenes (P(BT-E-BT)) show a better electrochemical activity with a high-quality film on electrodes compared to the polymers of polyether-bridged thiophenes (T-E-T) in a neutral media. The P(BT-E-BT) exhibited broad absorption in near infrared region with the band gaps (2.03–2.05 eV) and the good thermal stability. The versatile coloration change for P(BT-E-BT) films on a ITO glass electrode were achieved from salmon pink (neutral state) to blue–green and transmissive rusty red (oxidized states). Further electrochromic investigation implied that the polymer P(BT-E-BT) films showed moderate to high contrast ratios, good coloration efficiencies, low switching voltages, fast response times, excellent stabilities and colour persistence as potential electrochromic materials. [ABSTRACT FROM AUTHOR]

Toxic heavy-metal ions are well known to be severely harmful to human health. Therefore, the development of fast and sensitive methods for their detection has drawn a great attention in recent years. Herein, a sensitive electrochemical platform for the simultaneous determination of Cd 2 + , Pb 2 + , Cu 2 + , and Hg 2 + has been constructed based on N-doped graphene (NG) modified electrode using differential pulse stripping voltammetry (DPSV). NG was synthesized by a facile, efficient and green electrochemical method. The structure and composition of NG were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron microscopy (XPS) techniques, chronocoulometry and N 2 adsorption–desorption measurements. The NG modified electrode showed excellent catalytic activity for selective detection of Cd 2 + , Pb 2 + , Cu 2 + , and Hg 2 + due to its particular structure and unique electronic properties. Under optimal conditions, the limits of detection were estimated to be 0.05 μM for Cd 2 + and Hg 2 + , 0.005 μM for Pb 2 + and Cu 2 + , respectively. Finally, the method was applied to the simultaneous detection of trace metal ions in the tap water samples. [ABSTRACT FROM AUTHOR]

2’-Aminomethyl-3,4-ethylenedioxythiophene (EDOT-MeNH 2 ) showed unsatisfactory results when its polymerization occurred in organic solvent in our previous report. Therefore, a water-soluble EDOT derivative was designed by using hydrochloric modified EDOT-MeNH 2 (EDOT-MeNH 2 ·HCl) and electropolymerized in aqueous solution to form the corresponding polymer with excellent electrochromic properties. Moreover, the polymer was systematically explored, including electrochemical, optical properties and structure characterization. Cyclic voltammetry showed low oxidation potential of EDOT-MeNH 2 ·HCl (0.85 V) in aqueous solution, leading to the facile electrodeposition of uniform the polymer film with outstanding electroactivity. Compared with poly(2′-aminomethyl- 3,4-ethylenedioxythiophene) (PEDOT-MeNH 2 ), poly(2′-aminomethyl-3,4-ethylenedioxythiophene salt) (PEDOT-MeNH 3 + A − ) revealed higher efficiencies (156 cm 2 C −1 ), lower bandgap (1.68 eV), and faster response time (1.4 s). Satisfactory results implied that salinization can not only change the polymerization system, but also adjust the optical absorption, thereby increase the electrochromic properties. [ABSTRACT FROM AUTHOR]

• A machine learning strategy was applied for electrochemical sensor and supercapacitor. • The carbonized metal–organic framework showed excellent electrochemical response for niclosamide (NA) and good capacitance. • Both adsorption and binding energy were theoretically calculated and the structure of prepared material was optimized. Machine learning (ML) plays an important role in the electrochemical application of electrode materials. In this work, an emerging machine learning strategy for both electrochemical sensor and supercapacitor using carbonized metal–organic framework (C-ZIF-67) is proposed. The morphology and element analysis of C-ZIF-67 are characterized and further demonstrate the presence of C, N, O, Co elements. The ML model based on artificial neural network (ANN) algorithm as a powerful tool to realize intelligent analysis of niclosamide (NA), the derivative technique as an auxiliary means of voltammogram treatment to reduce personal error from data-reading and improve the sensitivity of electrochemical responses at very low concentrations, and the theoretical calculation is employed for both adsorption and binding energy, optimized structure of the prepared sensing material. The developed sensor displays excellent electrochemical response about 196.6-fold improvement compared with the bare GCE for NA, wider linear ranges of intelligent analysis from 1 nM to 9 μM with low limit of detection of 0.3 nM, and satisfactory practicability. ML model with ANN algorithm is also employed for predicting the performance of supercapacitor. The supercapacitor shows good performance with capacitance of 336.67 F/g at the current density of 2 A/g and excellent prediction with acceptable errors. This work will provide a new strategy for the development and electrochemical application of bifunctional electrode materials using the ML technique combined with theoretical calculation. [ABSTRACT FROM AUTHOR]

Ponceau 4R, an edible synthetic colorant used in drinks, syrups, and sweets, has been successfully detected using differential pulse voltammetry at a single-walled carbon nanotubes-modified composite electrode based on poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) and two derivatives thereof. The electrochemical parameters of three Ponceau 4R sensors, such as pH value, pre-concentration time, and scan rate, have been optimized, and their electrochemical performances have been compared. A poly(acrylate-modified 3,4-ethylenedioxythiophene- co -3,4-ethylenedioxythiophene):poly(styrene sulfonate)–single-walled carbon nanotubes–poly(vinyl alcohol)-modified electrode showed the best electrocatalytic activity, with the highest response current, lowest detection limit (1.8 nm), widest linear range (0.0055–110.6 μm), and best sensing stability. Additionally, the modified electrode has also been successfully employed for real sample analysis with soft drinks. Satisfactory results were obtained, demonstrating this to be an easy and effective approach for trace analysis of Ponceau 4R in food samples. [ABSTRACT FROM AUTHOR]

Biomass waste, a good candidate for advanced carbon materials for sustainable electrodes, is receiving more and more attention for high value-added materials because of its promising contribution to economic growth and sustainable development. We proposed a green co-hydrothermal approach to prepare lotus seedpods biochar (BC) decorated molybdenum disulfide (MoS 2) from waste lotus seedpods and precursors of MoS 2, and a portable, flexible, outdoor and inexpensive sensing platform for hyperin on the integrated flexible three-electrode using U-disk potentiostat with smartphone was successfully developed. Structure and properties of MoS 2 -BC were characterized, it was proved that BC improves microstructure and morphology, electronic conductivity, electrode stability and electrocatalytic properties of MoS 2. Attributing to these impressive features, the detection signal of hyperin was significantly amplified by the MoS 2 -BC modified glass carbon electrode (GCE) in detection range of 0.01–21 μΜ with detection limit (LOD) of 5 nM. It was worth mentioning that the MoS 2 -BC modified screen-printed electrode (SPE) performs hyperin detection in range of 100 nM - 3 μM with LOD 50 nM (S/N = 3). The practicability of the proposed method confirmed that the portable, on-site, low-cost, and outdoor detection of hyperin was feasible and practical in comparison with traditional both electrochemical sensing and HPLC methods. A portable U-disk potentiostat with smartphone for outdoor sensing of hyperin using lotus seedpods biochar decorated molybdenum disulfide on screen-printed electrode. [Display omitted] • Lotus seedpods biochar decorated molybdenum disulfide was prepared by co-hydrothermal method. • A portable U-disk potentiostat with smartphone for outdoor sensing of hyperin was developed. • The BC improved microstructure, conductivity, stability, and electrocatalytic capacity of MoS 2. • The proposed method was feasible for portable, on-site, inexpensive, and outdoor detection. [ABSTRACT FROM AUTHOR]

The development of ruthenium-based complexes or antimicrobial peptides are identified as a promising strategy for combating drug-resistant bacteria. In this work, four biphenyl-based antibacterial ruthenium complexes by targeting membrane integrity, which act as antimicrobial peptides mimics, were designed and synthesized. In vitro antimicrobial screening demonstrated that four complexes could absolutely inhibit the growth of Staphylococcus aureus (S. aureus) with MIC values ranging from 15.6 to 100 μg/mL. The most active complex Ru(Ⅱ)-1 (MIC = 15.6 μg/mL) could kill S. aureus through targeting the membrane integrity without detectably resistance frequencies. Further investigation including bacteria biofilm formation, hemolysin activity and checkerboard assay were performed as well. The results revealed that Ru(Ⅱ)-1 could inhibit the biofilm formation and α-hemolysis secretion in S. aureus at subinhibitory concentration. More interestingly, the combination use of Ru(Ⅱ)-1 and five traditional antibiotics showing synergistic effect. Finally, based on the mouse model of S. aureus skin infection, Ru(Ⅱ)-1 showed important antibacterial efficacy against S. aureus in vivo , and almost non-toxic against mouse tissue. Our study indicates that introducing membrane targeting ligands onto ruthenium complexes may be an underappreciated strategy for developing antibacterial agents. [Display omitted] • Ruthenium-based antibacterial agents by targeting bacterial membrane integrity were designed and synthesized. • Ru(Ⅱ)-1 could inhibit the biofilm formation and α-hemolysis secretion in S. aureus. • S. aureus hardly develop resistance to Ru(Ⅱ)-1. • Ru(Ⅱ)-1 could increase the antibacterial activity of some traditional antibiotics. • Ru(Ⅱ)-1 showed high efficacy against S. aureus in vivo and almost non-toxic to mouse tissue. [ABSTRACT FROM AUTHOR]

Aims: Considering individual variability in regards to the effects of orthokeratology (ortho-k) on myopia progression and controversies regarding the precise underlying mechanism, the aim of this study was to investigate several ocular measurements associated with axial length (AL) growth in children wearing ortho-k lenses.Methods: In this retrospective chart review, medical records of 53 Chinese children who wore ortho-k lenses over the course of 12 months were reviewed. Baseline variables included age at initiation of ortho-k wear, refractive error (spherical equivalent, SE), central corneal thickness (CCT), and flat and steep keratometry of corneal principal meridians. The change of anterior chamber depth (ACD) and the change of crystalline lens thickness (CLT) between baseline and the 12-month follow-up were also analyzed. The contributions of all analyzed variables to AL change were assessed using univariate and multivariate regression analyses.Results: Initially, the results of paired t-test showed that CLT and AL were significantly increased after 12 months of ortho-k wear compared with that at baseline (P = 0.001 and < 0.001). The ACD did not change significantly after 12 months compared with that at baseline (P = 0.491). Subsequently, univariate analyses showed that a reduced rate of AL elongation was found in children who were older age at initiation of ortho-k wear (P = 0.028), had greater SE (higher degree of myopia) at baseline (p = 0.006), had thicker CCT at baseline (P = 0.04), and had greater increase of CLT (P = 0.001) in 12 months. At last, only greater SE (higher degree of myopia) and greater increase of CLT were associated with smaller increases of AL in multivariable analyses, (P = 0.003 and 0.001).Conclusions: Both CLT and AL were significantly increased in children with overnight ortho-k wear after 12 months of follow-up. Greater baseline SE and greater increase of CLT were associated with less increase in AL during ortho-k wear in children with myopia. [ABSTRACT FROM AUTHOR]

Highlights: [•] The ƒ-SWCNT–β-CD modified electrode was fabricated for the sensitive determination of MP using differential pulse voltammetry. [•] The modified electrodes were applied to monitor the trace level of MP in agricultural practical samples. [•] The modified electrode exhibited fast current response, high sensitivity, good reproducibility, and satisfactory anti-interference ability. [Copyright &y& Elsevier]

Highlights: [•] C4-EDOT-COOH monomer with good solubility in water was synthesized by an efficient five-step route. [•] That acidic conditions were favorable for the electropolymerization of C4-EDOT-COOH. [•] The resulting high-quality polymer film can be employed for the fabrication of chemo/bio-sensors and optical sensors. [•] These as-prepared sensors can be applied to the simple, fast and sensitive detection of different analytes. [ABSTRACT FROM AUTHOR]

Highlights: [•] PBA was facilely electrosynthesized in the binary solvent system containing of acetonitrile and boron trifluoride diethyl etherate. [•] “On–off” type fluorescent sensor based on this polymer for highly selective, sensitive, and practical detection of Pd2+ was designed. [•] The possible mechanism between Pd2+ and PBA has been discussed and TEM preliminary proved the proposed mechanism. [•] This fluorescent CP-based sensor has been used to practically detect Pd2+ in agricultural crops and environment samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Highlights: [•] The necklace-like GO-MWCNTs nanohybrid was facilely synthesized by ultrasonication. [•] The nanocomposites can be effectively used for the detection of Azithromycin. [•] Low detection limit with wide linear range could be obtained. [•] The method was applied to determine Azi in real samples. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, we for the first time propose a new one-step electrochemical redox route for the synthesis of high quality graphene–poly(3,4-ethylenedioxythiophene) (graphene–PEDOT) nanocomposite film based on simultaneous electrodeposition of PEDOT and electrochemical reduction of graphene oxide (GO) on a glassy carbon (GC) electrode. Data from scanning electron microscopy (SEM), UV–vis spectroscopy (UV–vis) and electrochemical impedance spectroscopy (EIS) demonstrated that the graphene/PEDOT nanocomposite film was successfully synthesized. The obtained graphene–PEDOT nanocomposite film showed large specific area, high conductivity, good biocompatibility, and fast redox properties and had encapsulated structures, which make it a novel material promising for biological applications. As an enzyme model, ascorbate oxidase (AO) was entrapped onto the film-modified electrode and used to construct an electrochemical ascorbic acid biosensor. The modified electrode showed good electrocatalytic performance towards ascorbic acid with high selectivity, wide linear range, and good stability. The facile and easy electrochemical approach used for the preparation of graphene–PEDOT/AO may open up new horizons in developing of cost effective biosensors. [Copyright &y& Elsevier]

It is an urgent need to exploit a potentially green, cost efficient and eco-friendly strategy for the utilization of waste kudzu vine. We developed a one-step green preparation of kudzu vine biochar (BC) decorated graphene-like molybdenum selenide (MoSe 2) with the oxidase-like activity as intelligent nanozyme sensing platform for voltametric detection of hesperetin (HP) in orange peel using the in-situ hydrothermal synthesis method. The structure and properties of MoSe 2 -BC was characterized, and found that BC significantly improved electrochemical cycle stability, electronic conductivity, electrochemical active area, and electrocatalytic activity of MoSe 2. The oxidase-like activity of MoSe 2 -BC was confirmed by the oxidization of the colorless substrate 3,3′,5,5′-tetramethylbenzidine (TMB) to form blue products and the change of absorbance intensity of UV–vis absorption spectra. The MoSe 2 -BC exhibited excellent electrochemical sensing performance for the detection of HP in wide linear ranges from 10 nM to 9.5 μM with a low limit of detection of 2 nM using differential pulse voltammetric method. An emerging machine learning technique is used to realize the intelligent sensing of HP, and the performance evaluation of regression analysis was selected to evaluate this technique. This work will provide a guidance for the preparation and application of biochar decorated graphene-like nanomaterials with the oxidase-like activity and the development of intelligent nanozyme sensing platform. [Display omitted] • The waste kudzu vine is utilized through the hydrothermal carbonization. • A facile and scalable approach is employed for green synthesis of MoSe 2 -BC. • A nanozyme sensor is developed for electrochemical detection of hesperetin. • A machine learning technique is used for the intelligent analysis of hesperetin. [ABSTRACT FROM AUTHOR]

The preparation process of MXene@PDA/NH 2 -MWCNTs modified electrode and its application for AAP determination. [Display omitted] • Hierarchical MXene@PDA/NH 2 -MWCNTs was prepared. • PDA enhances the interfacial bonding stability between MXene and NH 2 -MWCNTs. • MXene@PDA/NH 2 -MWCNTs was utilized as a platform for electrochemical sensing of AAP. • MXene@PDA/NH 2 -MWCNTs showed ultra-sensitive detection towards AAP. • The method was successfully applied for analysis of AAP in real samples. MXene/MWCNTs nanohybrid has been deemed as ideal electrode material owing to its unique structure, and physical and chemical properties. However, the bonding between MXene and MWCNTs reported in most literatures mainly depends on the π-π, hydrogen bonds, and electrostatic interaction, which limit the mechanical stability of the materials. To address this issue, herein, a facile approach was developed to in situ cross-link amino functionalized multi-carbon nanotubes on polydopamine functionalized MXene (MXene@PDA/NH 2 -MWCNTs). The NH 2 -MWCNTs can be well and firmly distributed on the MXene@PDA via Michael addition reaction. The resultant MXene@PDA/NH 2 -MWCNTs composite displays hierarchical structure, large specific surface area, good conductivity and electrocatalytic ability. Attributing to these characters, the composite modified electrode presents prominent sensing performance toward the determination of acetaminophen (AAP) with good linear response from 5.0 nM to 10.0 μM and 10.0 μM to 60.0 μM, along with a low detection limit of 1.0 nM (S/N = 3). Furthermore, the MXene@PDA/NH 2 -MWCNTs electrode shows acceptable reproducibility, good selectivity and excellent stability. This method is also employed to detect AAP in the actual samples with approving results. [ABSTRACT FROM AUTHOR]

The green preparation of the a-MoS x -BM nanocomposite for smart sensing baicalin. [Display omitted] • The a-MoS x -BM nanocomposite as sensing platform was prepared by a green hydrothermal method; • LSSVM displayed more superiority in practical application for smart sensing compared with ANN. Green and sustainable development provides a new idea for solving environmental pollution issues of rural biomass wastes. Amorphous molybdenum sulfide (a-MoS x) nanocomposite based on biochar microsphere (BM) as voltametric sensing platform for smart analysis of baicalin in real sample was facilely prepared. Pomelo peel was employed as the carbon source for improving electronic conductivity and environmental stability and electrocatalytic capacity of a-MoS x. A mixture consisted of the precursor of both a-MoS x and BM were treated by a co-hydrothermal method. The a-MoS x nanocomposite with porous BM was formed by centrifuging, washing, drying, pulverizing, and calcining. The structure and properties of the as-obtained nanocomposite were characterized, and the electrochemical behaviors of baicalin, parametric conditions and performance of the as-prepared sensor were investigated. Peak currents recorded by differential pulse voltammetry is proportional to baicalin concentrations in wide linear ranges from 10 nM to 5 μM with a low limit of detection of 2 nM. Machine learning algorithms like least squares support vector machine and artificial neural network was built to realize smart analysis and digital output for baicalin. Good cyclic stability, excellent voltammetric response, and satisfactory practicability will provide a promising electrochemical sensing platform for facile preparation of two-dimension nanomaterials functionalized with biochar derived from agroforestry biomass. [ABSTRACT FROM AUTHOR]

[Display omitted] • A porous poplar flower-like PEDOT-MeOH/PEG/WS 2 composite was fabricated. • The PEDOT-MeOH/PEG/WS 2 showed a high capacitance of 461.5 mF cm−2 at 5 mV s−1. • The device presented a specific energy of 8.72 × 103 μWh cm−2 at 2.62 × 105 μW cm−2. • The capacitive retention was 83.6% after 5000 charge-discharge cycles. The morphology of electrode material is generally critical to affecting their electrochemical performance. Here, a porous poplar flower-like PEDOT-MeOH/PEG/WS 2 hybrid material is successfully prepared using a simply co-electrodeposition method. With the assistance of poly(ethylene glycol) (PEG), the chemically exfoliated WS 2 nanosheets are doped into poly(hydroxymethyl-3,4-ethylenedioxythiophene) (PEDOT-MeOH) film. The formation of a porous poplar flower-like PEDOT-MeOH/PEG/WS 2 composite is proved by scanning electron microscopy, transmission electron microscopy, infrared spectra, energy-dispersive X-ray spectrometry and X-ray photoelectron spectroscopy. The maximum capacitance of the composite reaches 461.5 mF cm−2, which is 1.6 times greater than that of PEDOT-MeOH/PEG film. As-fabricated PEDOT-MeOH/PEG/WS 2 composite can keep 85.8% of the initial areal capacitance after 5000 cycles. Additionally, PEDOT-MeOH/PEG/WS 2 -based symmetrical supercapacitor presents a capacitive capacity of 62.7 mF cm−2 at 0.5 mA cm−2, specific energy of 8.72 × 103 μWh cm−2 at 2.62 × 105 μW cm−2, and capacitive retention of 83.3% after 5000 cycles with a 100% coulombic efficiency. The capacitance improvement of PEDOT-MeOH/PEG/WS 2 composite is closely related to porous poplar flower-like structure as well as the cooperation-enhancing effect between PEDOT-MeOH and WS 2. These results imply that PEDOT-MeOH/PEG/WS 2 composite will have great potential application in the field of the energy storage. [ABSTRACT FROM AUTHOR]

• Hierarchical PEDOT@MoS 2 composite was fabricated by electrochemical co-deposition. • As a separate electrode, it exhibits ultra-high capacitance and remarkable cycling stability. • The assembled supercapacitor delivers high energy density and excellent cycling stability. Hierarchical structural PEDOT@MoS 2 nanocomposite is synthesized via a facile electrochemical co-deposition of the intercalation of PEDOT into flower-like MoS 2 microspheres. The SEM, TEM, and other characterization results demonstrate the hierarchical PEDOT@MoS 2 composite with an enlarged interlayer spacing of MoS 2 to 1.02 nm, in which PEDOT nanoparticles act as intercalation, and flower-like MoS 2 microspheres are used as a substrate for growth. The electrochemical characterizations indicate that the PEDOT@MoS 2 electrode has an ultra-high specific capacitance of 4418 mF cm−2 at 2 mA cm−2 and remarkable cycling stability, retaining 100% of the initial capacitance at a high current density of 100 mA cm−2 after 10,000 cycles. The symmetric PEDOT@MoS 2 supercapacitor presents a high energy density of 88.3 mWh cm−2 at 60 mW cm−2, and outstanding cycling stability (93% after 10,000 cycles). These prominent electrochemical performances are attributed to the expanded interlayer spacing, the synergistic effect between PEDOT and MoS 2 , the low resistance, along with the PEDOT@MoS 2 porous structure, indicating great potential applications of the PEDOT@MoS 2 electrode in the energy storage field. [ABSTRACT FROM AUTHOR]

A rapid-responsive and high-selectivity colorimetric-fluorescent sensor for the detection of bisulfite and its application in real samples. • A simple but effective fluorescent sensor BCVTI for SO 2 derivatives was developed based on ICT mechanism. • BCVTI has highly selective and sensitive, with a detection limit of 3.3 nM. • BCVTI can be used to detect SO 2 derivatives in real food samples including wine and white sugar. Based on the Michael addition mechanism, a colorimetric fluorescence sensor (E)-2-(2-(9-benzyl-9 H -carbazol-3-yl)vinyl)-3-methylbenzo[ d ]thiazol-3-ium iodide (BCVTI) that specifically recognizes HSO 3 − was constructed with benzothiazole iodide as the acceptor unit and benzylcarbazole as the donor unit. The sensor BCVTI exhibited orange-red fluorescence by itself due to the intramolecular charge transfer (ICT) effect. When HSO 3 − was added, BCVTI underwent nucleophilic addition, which destroyed the ICT effect and quenched the fluorescence. At the same time, the color of the BCVTI solution changed from orange-red to colorless, which can detect HSO 3 − by naked eyes. BCVTI had high selectivity, and its sensing mechanism had been studied by nuclear magnetism and mass spectrometry. In addition, BCVTI can complete the detection of HSO 3 − within 4 min, with a detection limit as low as 3.3 nM. Finally, the fluorescence sensor BCVTI was also applied to the trace detection of HSO 3 − in mineral water, wine, and white sugar with satisfactory results. All these results showed that BCVTI could be as a practical sensing platform for analysis of HSO 3 − in food samples. [ABSTRACT FROM AUTHOR]

An active material electrode with high areal specific capacitance is needed for a high-performance supercapacitor, but it is difficult to achieve this goal for PEDOT-based composites. Here, a novel hierarchical core/shell PEDOT@MoS 2 composite was assembled by the electrochemical co-deposition of EDOT and MoS 2 submicron spheres. The SEM, TEM images of the as-obtained composite explicitly reveal the core/shell heterostructure of PEDOT@MoS 2 with a diameter of about 800 nm. The electrochemical characterizations show that the optimized PEDOT@MoS 2 composite possesses a high specific capacitance of 2540 mF cm−2 at 1 mA cm−2 and excellent capacitance retention of 98.5% after 5000 cycles at a high current density of 100 mA cm−2. The assembled P@M-4//PEDOT asymmetric supercapacitor shows a high energy density of 937 Wh m −2 at 6500 W m −2, and outstanding cycling stability with capacitance retention of 100% after 5000 cycles. It is proposed that the enhanced performances are attributed to the robust hierarchical core/shell structures and the synergic effect between PEDOT and MoS 2 , which is expected to become a promising candidate for applications in high-performance supercapacitors. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Luteolin (LUT) is one of the biologically active functional components, which was widely used in pharmacological applications. Thus, development of sensitive analytical methods for LUT determination is highly desired. In this work, Ti 3 C 2 -MXene/ZIF-67/CNTs heterostructure was exploited as a new electrochemical sensing platform for the sensitive determination of LUT. For the design of composite, the in-situ growth of ZIF-67 on CNTs surface ensures the stability of their binding and enhances the synergetic catalysis. Conductive MXene as matrix for the loading of ZIF-67/CNTs can promote the catalytic ability of composite. Electrochemical results show that the MXene/ZIF-67/CNTs modified electrode displays preeminent electrocatalytic activity and enhances electrochemical response to the redox reaction of LUT, ascribing to the synergistic effect of ZIF-67/CNTs and MXene. Upon the optimization of experimental parameters, e.g., pH, enrichment time, the sensor based on MXene/ZIF-67/CNTs composite exhibits excellent performance with wide linear relationship ranging from 0.1–1000 nM and a low limit of detection (LOD) of 0.03 nM (S/N = 3). Besides, MXene/ZIF-67/CNTs electrode performs high selectivity, stability, and acceptable reproducibility. Furthermore, the constructed sensor was successfully utilized to detect LUT in real samples with satisfactory recovery. A novel electrochemical sensor was fabricated based on MXene/ZIF-67/CNTs nanocomposite for the detection of luteolin. Unlabelled Image • Ti 3 C 2 MXene/zeolite imidazolate framework-67/carbon nanotubes nanocomposite (MXene/ZIF-67/CNTs) was synthesized. • MXene/ZIF-67/CNTs showed high specific surface area and good conductivity. • A novel electrochemical sensor for luteolin detection was fabricated based on MXene/ZIF-67/CNTs with high sensitivity. • This sensor was successfully applied for the detection of luteolin in real sample. [ABSTRACT FROM AUTHOR]

• PEDOT: PSS/rGO fibers are prepared by easily-accessible hydrothermal confinement reaction. • PEDOT:PSS/rGO fiber with simultaneously enhanced capacitance and mechanical properties can be obtained. • The fiber-shaped supercapacitor shows a high specific energy density of 10.68 Wh•kg−1 at the power density of 81.25 W kg−1. Implantable, flexible and easily reconfigurable supercapacitors with high power and energy densities are considered necessary for the development of portable and wearable electronics. However, obtaining a fiber-incorporating high electrochemical performance and fracture elongation remains a huge challenge. Here, we prepare a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid)/reduced graphene oxide (PEDOT:PSS/rGO) fiber (PGF) with high-quality electrodes for supercapacitors by easily-accessible hydrothermal confinement reaction. The optimized P 3 G 7 F exhibits improved electrochemical performance including a high specific capacitance (C s) of 249.5 F g −1 at 0.5 A g −1 and good cycling stability. Moreover, after introducing the PEDOT:PSS, the elongation at break of the P 3 G 7 F is doubled to 13.9%. A symmetric supercapacitor (SSC) based on the P 3 G 7 F displays a high specific energy density of 10.68 Wh kg−1 at a specific power density of 81.25 W kg−1. The improved performance of the fabricated composite fiber is attributed to the unique structures of the rGO and PEDOT:PSS and their synergistic effect. This study introduces an opportunity for the development of next-generation flexible and wearable devices. PEDOT:PSS/rGO fibers are prepared via easily-accessible hydrothermal confinement method and the PEDOT:PSS/rGO fibers exhibit good capacitance and mechanical properties. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Flexible PEDOT/paper with high electrochemical performance and excellent stability was successfully fabricated for supercapacitor. • The PEDOT/paper was prepared via vapor phase polymerization. • PEDOT/paper showed excellent flexibility and stability. • PEDOT/paper displayed high areal capacitance of 639 m F cm−2 at 1 mA cm-2. • PEDOT/paper displayed high specific capacitance of 118 F g−1 at 1 mA cm-2. Currently, electrodes with favorable flexibility, high capacitance and conductivity is vital to the development of supercapacitors. However, it is still a great challenge to manufacture these materials simply and inexpensively. Herein, vapor phase polymerization (VPP) is applied in this work to deposit poly(3,4-ethylenedioxythiophene) (PEDOT) on the flexible paper, which can prepare electrode on a large scale. The fabricated PEDOT/paper possesses porous structure, which can facilitate sufficient contact between electrolyte and electrode material, and benefit for ions diffusion. The effect of different amount of PEDOT on the electrochemical properties of the PEDOT/paper is investigated. As expected, the prepared electrode exhibits high areal capacitance of 639 m F cm−2 and good conductivity of 78 S cm-1, remarkable stability under different bending angle conditions, which can be directly used as electrode for flexible and light-weight energy storage devices. It is believed that the method is useful to improve both electrical conductivity and capacitance of the PEDOT/paper, and further to optimize the electrochemical performance of the prepared material. [ABSTRACT FROM AUTHOR]

• Few-layered crumpled porous N-doped graphene was prepared using nitroaromatic molecules as N sources. • Nitroaromatic molecules effectively suppressed the aggregation of N-doped graphene. • As-obtained 5-NIGN had high specific capacitance of 457.4 F g−1 and long cycle life. Nitroaromatic pollutants with unusually strong adsorption affinity are highly attractive candidates for creating 2D molecular assemblies on the surface of graphene, which is crucial to prepare high-quality N-doped graphene by post-treatment. Herein, the few-layered crumpled N-doped graphene (5-NIGN) with high N content is successfully prepared by mixing 5-nitroindole (5-NI), ammonia, and graphene oxide (GO) and using a simple hydrothermal method followed by the post-treatment process of vacuum freeze-drying and annealing. It is found that the rapid assembly of 5-NI effectively suppresses the aggregation of the products in the reduction process of GO, so that the thickness of as-prepared 5-NIGN is 4.21 nm, very close to that of GO (4.01 nm). Compared with the N-doped graphene (GN) derived from the system of GO containing ammonia (341 F g−1), 5-NIGN exhibits higher capacitance of 457.4 F g−1 at 1 A g−1 and prominent long-term life (115% of capacitance maintenance upon 10,000 cycles) within the voltage window of 1.0 V. Furthermore, the supercapacitor assembled by 5-NIGN electrodes can deliver the energy density of 15.5 Wh kg−1~18.5 Wh kg−1 at the power density of 8000 W kg−1~800 W kg−1. These results indicate that the 5-NIGN material will have potential advantages in the realm of electrochemical energy storage. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The introduction of fluorine into a compound or material is known to impart a range of interesting functionalities; however, the poor electrochemical capacity of existing fluorinated polymers limits their application in the field of energy storage. Thus, we herein report the successful preparation of several fluorinated polyindole materials exhibiting high energy storage behaviours using a simple electropolymerization strategy. Scanning and transmission electron microscopic images reveal that the monofluorinated polyindoles are mainly composed of one-dimensional (1D) nanofibers and nanorods, whereas 1D nanowires and two-dimensional (2D) nanosheets are obtained for the difluorinated polyindoles. Interestingly, the prepared fluorinated polyindoles are found to exhibit the highest specific capacitances among all reported fluorinated materials (i.e., 261–528 F g−1 at 18 A g−1). In addition, they exhibit a good cycle stability as well as a high rate capability. Our results indicate that fluorinated nano-polyindoles can be considered as promising electrode materials for energy storage applications. [ABSTRACT FROM AUTHOR]

• A reaction-based colorimetric-fluorescent sensor ASHTI was synthesized. • ASHTI with D -π-A structure emitted red fluorescence that could effectively increase signal-to-noise ratio. • ASHTI displayed high selectivity and sensitivity to HSO 3 − in aqueous solution. • ASHTI could initial screen and accurately analyze environmental samples containing HSO 3 −. The colorimetric-fluorescent sensor ASHTI , synthesized by simple method, could sensitively and selectively sense bisulfite (HSO 3 −) in phosphate-buffered saline solution (pH 7.4) via the Michael-addition mechanism. ASHTI with D -π-A structure emitted red fluorescence, which could minimize the background noises and increase signal-to-noise ratio. It showed higher selectivity to HSO 3 − than other anions and cations, and the low detection limit was 0.27 µM. Also, 1H NMR and LC-MS spectra were employed to confirm its sensing mechanism. The simple, quick, and convenient ASHTI test strips were prepared. And the naked eye could easily observe that the red color of these test strips gradually faded with increasing the concentration of HSO 3 −. Then ASHTI test strips were used for detecting HSO 3 − in river water and paddy water successfully. Also, ASHTI solution was applied to fluorescence sense HSO 3 − in paddy water, river water, lake water, and tap water with satisfactory results. All these results demonstrated that ASHTI could be applied for the initial screening of environmental samples containing HSO 3 − and accurately analyze the HSO 3 − content in environment field. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) MXenes have emerged as an attractive platform to construct electrochemical biosensors because of their excellent electronic properties. However, the self-restacking and agglomeration of MXenes lead to unsatisfactory performance. To overcome these drawbacks, herein, the treatment of Ti 3 C 2 MXene through a simultaneous oxidation and alkalization progress was proposed for the synthesis of 3D sodium titanate nanoribbons (M-NTO). Furthermore, conductive poly(3,4-ethyl-enedioxythiophene) (PEDOT) was anchored on 3D M-NTO to enhance its conductivity. The resulting M-NTO-PEDOT composite possessed high specific surface area, fast electron transfer ability, as well as excellent biocompatibility. Subsequently, Au nanoparticles (AuNPs) were electrodeposited on the surface of M-NTO-PEDOT for prostate specific antigen (PSA) antibodies immobilization. Thus, a facile electrochemical label-free immunosensor for sensitive detection of PSA was fabricated on a basis of AuNPs/M-NTO-PEDOT composite. Benefitting from the synergistic effects of M-NTO, PEDOT and AuNPs, the fabricated M-NTO-PEDOT based immunosensor exhibited good analytical performance with a low limit of detection (LOD) of 0.03 pg L−1 (S/N = 3). Additionally, high stability, good selectivity and recovery were achieved in the process of PSA detection in human serum samples. A novel electrochemical immunosensor was fabricated based on M-NTO-PEDOT/AuNPs composite for the detection of Prostate Specific Antigen. Unlabelled Image • Hierarchical Ti 3 C 2 MXene-derived sodium titanate nanoribbons (M-NTO)/PEDOT was synthesized. • M-NTO-PEDOT showed high specific surface area, good biocompatibility and conductivity. • A novel immunosensor for PSA detection was fabricated based on AuNPs/M-NTO-PEODT. • AuNPs/M-NTO-PEODT as signal amplifier greatly improved the detection sensitivity. • This immunosensor was successfully applied for the detection of PSA in real serum sample. [ABSTRACT FROM AUTHOR]

Fluoropolymers have great values in the scientific research and the industrial application, but poor electrochemical properties restricted their use as charge storage materials. In this work, we developed a high-performance poly(5-fluoroindole) (5-PFIn) as charge storage material by simple electrodeposition of 5-fluoroindole in acetonitrile solution containing 0.1 M Bu 4 NBF 4. The morphologies, structures and electrochemical properties of as-prepared 5-PFIn were studied by SEM, FT-IR, UV–vis, BET and electrochemical techniques, respectively. The electrochemical results indicated that the 5-PFIn nanowires in 1.0 M H 2 SO 4 electrolyte showed a full-covered strongly responsive redox behavior between −0.4 V and 0.85 V, which remarkably differed from polyindole (PIn) and poly(5-methoxyindole) (5-PMeOIn) and poly(indole-5-carboxylic acid) (5-PICA). As a result, 5-PFIn exhibited high specific capacitance of 416 F g−1 at 10 A g−1, good cycling stability of 83% after 5000 cycles and slow self-discharge behavior, which were superior to those of PIn (103 F g−1, 68%), 5-PMeOIn (114 F g−1, 70%) and 5-PICA (286 F g−1, 70%). These results indicated that the fluorine-substituted conjugated PIn will be one of the most promising fluoropolymers electrode materials for supercapacitor application. [ABSTRACT FROM AUTHOR]

This review (with 155 refs.) summarizes the progress made in the past few years in the field of electrochemical sensors based on graphene-derived materials for the determination of heavy metal ions. Following an introduction of this field and a discussion of the various kinds of modified graphenes including graphene oxide and reduced graphene oxide, the review covers graphene based electrodes modified (or doped) with (a) heteroatoms, (b) metal nanoparticles, (c) metal oxides, (d) small organic molecules, (e) polymers, and (f) ternary nanocomposites. Tables are provided that afford an overview of representative methods and materials for fabricating electrochemical sensors. Furthermore, sensing mechanisms are discussed. A concluding section presents new perspectives, opportunities and current challenges.Schematic illustration of electrochemical sensor for heavy metal ion sensing based on heteroatom-doped graphene, metal-modified graphene, metal-oxide-modified graphene, organically modified graphene, polymer-modified graphene, and ternary graphene based nanocomposites. [ABSTRACT FROM AUTHOR]

A promising electrochemical sensing platform for the detection of ponceau 4R in food has been fabricated based on the carboxylated graphene oxide (GO-COOH), metal-organic framework (MOF) UIO-66-NH 2 , and poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). To this end GO-COOH was covalently coupled with UIO-66-NH 2 through amide reaction, endowing the material (GO-CONH-UIO-66) unique hierarchical pores and high chemical stability and as a result improving the conductivity of MOF and the dispersion of GO. After the addition of PEDOT:PSS into GO-CONH-UIO-66, the continuity and conductivity of the composite (PEDOT:PSS/GO-CONH-UIO-66) have been further enhanced, due to the high conductivity, favorable film-forming, and hydrophilic properties of PEDOT:PSS. Systematic electrochemical experiments confirm that the PEDOT:PSS/GO-CONH-UIO-66/GCE shows satisfactory electrochemical sensing properties towards the detection of ponceau 4R, with a wide linear detection range of 0.01-30 μM, a low limit of detection of 3.33 nM, and a high sensitivity of 0.606 μA μM -1  cm -2 . The PEDOT:PSS/GO-CONH-UIO-66 sensing platform was successfully used to detect ponceau 4R in beverage, and the detection results were compared with  high-performance liquid chromatography. As a result, the PEDOT:PSS/GO-CONH-UIO-66 composite shows a promising application prospect for rapid detection of ponceau 4R in food and will play significant role in food safety detection and supervision., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)