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Type 2 diabetes (T2D) is associated with pancreatic β-cell dysfunction, which can be induced by oxidative stress or/and the aggregation of human islet amyloid polypeptide (hIAPP). Therefore, ONOO- and hIAPP become the crucial targets of T2D treatment. Previously, we found heme could be an effective inhibitor of hIAPP aggregation. However, heme causes serious toxic effects on cells, tissues and organs through oxidative stress, which block it as a potential drug candidate for T2D treatment. 5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrinato iron(III) chloride (FeTPPS), a water-soluble derivative of heme, is recognized as a high-efficient ONOO- decomposition catalyst, which is reported to have a great therapeutic potential in ONOO- -related diseases, including T2D. Here, we explored the potentiality of FeTPPS to be an inhibitor of hIAPP aggregation and the protective effects on cytotoxicity of hIAPP aggregation. It was found that the interaction between FeTPPS and hIAPP remarkably affected hIAPP fibrillation by both stabilizing hIAPP monomers and disaggregating the long fibrils into small oligomeric species. Furthermore, unlike heme, the addition of FeTPPS completely reversed the cytotoxicity and ROS level induced by hIAPP, which was consistent with its strong inhibitory activity. These results implied that FeTPPS could be a promising agent for the treatment of T2D.

A novel composite, polydopamine-modified Mo2C/MoO2 nanoparticles (HD-Mo2C/MoO2), as anode electrocatalyst for microbial fuel cells (MFCs), is synthesized via carbon thermal reduction and following in situ polydopamine modification. The physical and electrochemical characterizations show that Mo2C/MoO2 nanoparticles can be well dispersed through polydopamine modification and the resulting HD-Mo2C/MoO2 exhibits excellent electrocatalytic activity compared with unmodified Mo2C/MoO2. The MFC using HD-Mo2C/MoO2 as anode electrocatalyst achieves a maximum output power density of 1.64 ± 0.09 W m−2, which is 39% higher than that using Mo2C/MoO2 (1.18 ± 0.08 W m−2) as anode electrocatalyst. This excellent performance is attributed to modification of PDA, HD-Mo2C/MoO2 shows better hydrophilicity and electrocatalytic activity toward the direct oxidation of bacterial metabolites than unmodified Mo2C/MoO2.

Terthiophene (3THP) is evaluated as an electrolyte additive for improving cyclic stability of lithium nickel manganese oxide (LiNi 0.5 Mn 1.5 O 4 ) cathode for high energy density lithium-ion batteries. Charge/discharge tests demonstrate that 3THP is effective for improving the cyclic stability of LiNi 0.5 Mn 1.5 O 4 . With applying only 0.25% 3THP in a standard (1 M LiPF 6 in EC and DMC, 1/2 in volume) electrolyte, the capacity retention of Li/LiNi 0.5 Mn 1.5 O 4 cell after 350 cycles at 1C (1C = 147 mA g −1 ) under 4.9 V was improved from 50% to 91%, which is among the best that have been reported in literatures although the content of 3THP is far lower than those achieved by applying other additives. The physical characterizations from scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction, indicate that a thin cathode film has been formed on LiNi 0.5 Mn 1.5 O 4 particles, which suppresses the decomposition of electrolyte and protects LiNi 0.5 Mn 1.5 O 4 from structural destruction.

Cobalt-modified molybdenum dioxide nanoparticles highly dispersed on nitrogen-doped carbon nanorods (Co–MoO2/NCND), are synthesized from anilinium trimolybdate dihydrate nanorods, for the performance improvement of microbial fuel cell based on a mixed bacterial culture. Electrochemical measurements demonstrate that the as-synthesized Co–MoO2/NCND exhibits excellent electrocatalytic activity for the charge transfer on anode, providing the cell with a maximum power density of 2.06 ± 0.05 W m−2, which is strikingly higher than the bare carbon felt anode (0.49 ± 0.04 W m−2). The excellent performance of Co–MoO2/NCND is ascribed to the increased electronic conductivity of carbon nanorods by N-doping, the high ability of MoO2 to enrich electroactive bacteria, as demonstrated by high-throughput sequencing, and the enhanced activity of MoO2 by Co-modifying toward redox reactions in electroactive bacteria. This report provides a new concept of anode electrocatalyst fabrications for the application of microbial fuel cells in electricity generation and wastewater treatment.

We report a novel anode electrocatalyst, iron carbide nanoparticles dispersed in porous graphitized carbon (Nano-Fe3C@PGC), which is synthesized by facile approach involving a direct pyrolysis of ferrous gluconate and a following removal of free iron, but provides microbial fuel cells with superior performances. The physical characterizations confirm the unique configuration of iron carbide nanoparticles with porous graphitized carbon. Electrochemical measurements demonstrate that the as-synthesized Nano-Fe3C@PGC exhibits an outstanding electrocatalytic activity toward the charge transfer between bacteria and anode. Equipped with Nano-Fe3C@PGC, the microbial fuel cells based on a mixed bacterium culture yields a power density of 1856 mW m−2. The resulting excellent performance is attributed to the large electrochemical active area and the high electronic conductivity that porous graphitized carbon provides and the enriched electrochemically active microorganisms and enhanced activity towards the redox reactions in microorganisms by Fe3C nanoparticles.

TiO2 nanocones (TiO2-NCs) are constructed into arrayed spherical shells through a liquid-phase deposition reaction with polymer template, to improve the performance of TiO2 as anode of lithium ion microbattery. The morphology and structure characterizations indicate that TiO2 grows into nanocones with exposed {001} facets and is self-assembled into mesoporous structure. Meanwhile, macroporous channels are formed among the arrayed shells. Electrochemical measurements demonstrate that the TiO2-NCs reveal excellent performance in terms of improved lithium storage property and rate capability. The improved performance can be ascribed to the channel structure for the convenience of ionic transportation and the high-energy facets for the improvement of ionic reactivity.

A composite, polyaniline (PANI)/mesoporous tungsten trioxide (m-WO(3)), was developed as a platinum-free and biocompatible anodic electrocatalyst of microbial fuel cells (MFCs). The m-WO(3) was synthesized by a replicating route and PANI was loaded on the m-WO(3) through the chemical oxidation of aniline. The composite was characterized by using X-ray diffraction, Fourier transform infrared spectrum, field emission scanning electron microscopy, and transmission electron microscopy. The activity of the composite as the anode electrocatalyst of MFC based on Escherichia coli (E. coli) was investigated with cyclic voltammetry, chronoamperometry, and cell discharge test. It is found that the composite exhibits a unique electrocatalytic activity. The maximum power density is 0.98 W m(-2) for MFC using the composite electrocatalyst, while only 0.76 W m(-2) and 0.48 W m(-2) for the MFC using individual m-WO(3) and PANI electrocatalyst, respectively. The improved electrocatalytic activity of the composite can be ascribed to the combination of m-WO(3) and PANI. The m-WO(3) has good biocompatibility and PANI has good electrical conductivity. Most importantly, the combination of m-WO(3) and PANI improves the electrochemical activity of PANI for proton insertion and de-insertion.

A composite of nickel and β-molybdenum carbide (Ni/β-Mo2C) was prepared from solution derived precursor and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and Brunauer-Emmett-Teller (BET). The activity of Ni/β-Mo2C as noble-metal-free anodic electrocatalyst of microbial fuel cell (MFC) based on Klebsiella pneumoniae (K. pneumoniae) was investigated by electrochemical measurements. The results from voltammetric measurements show that Ni/β-Mo2C has high electrocatalytic activity towards the oxidation of formate, lactate, ethanol, and 2,6-di-tert-butyl-p-benzoquinon (2,6-DTBBQ), which are the main metabolites of K. pneumoniae. The results from polarization curve measurement indicate that the MFC using Ni/β-Mo2C as anodic electrocatalyst delivers a higher power density than the MFC using β-Mo2C as anodic electrocatalyst. Ni/β-Mo2C provides the MFC based on K. pneumoniae with a novel noble-metal-free anodic electrocatalyst of high activity.

In this paper, we reported an improved process for the preparation of PtRu/CNTs, which involves the adsorption of Pt and Ru ions on CNTs in aqueous solution and the reduction of the adsorbed Pt and Ru ions on CNTs in ethylene glycol. The surface morphology, structure, and compositions of the prepared catalyst were studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), and energy-dispersive spectrometer. TEM observation showed that the particles size of the prepared PtRu alloy was in the range of 2–5 nm, XRD patterns confirmed a face-centered cubic crystal structure. The activity and stability of the prepared catalyst toward methanol oxidation were studied in 0.5 M H2SO4 + 1 M CH3OH solution by cyclic voltammetry, chronoamperometry, and chronopotentiometry. The electrochemical results showed that the prepared catalyst exhibited higher activity and stability toward methanol oxidation than commercial PtRu/C with the same loading amount of Pt and Ru.

In this paper, Ni/β-Mo2C(S) and Ni/β-Mo2C(G) were prepared from solution-derived precursor with two different carbon sources (starch and glucose) and tested as anodic noble-metal-free catalysts in air-cathode microbial fuel cells (MFCs). The carburized catalyst samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET). The activity of the electrocatalyst towards the oxidation of several common microbial fermentation products (formate, lactate, and ethanol) was studied for MFC based on Klebsiella pneumoniae conditions. The composite MFC anodes were fabricated, and their catalytic behavior was investigated. With different carbon sources, the crystalline structure does not change and the crystallinity and surface area increase. The electrocatalytic experiments show that the Ni/β-Mo2C(G) gives the better bio- and electrocatalytic performance than Ni/β-Mo2C(S) due to its higher crystallinity and BET surface area.

Ni3Mo3C was prepared by a modified organic colloid method and explored as anode catalyst for high-performance microbial fuel cell (MFC) based on Klebsiella pneumoniae (K. pneumoniae). The prepared sample was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET). The activity of the sample as anode catalyst for MFC based on K. pneumoniae was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and polarization curve measurement. The results show that the adding of nickel in Mo2C increases the BET surface area of Mo2C and improves the electrocatalytic activity of Mo2C towards the oxidation of microbial fermentation products. The power density of MFC with 3 mg cm(-2) Ni3Mo3C anode is far higher than that of the MFC with carbon felt as anode without any catalyst, which is 19 % higher than that of Mo2C anode and produced 62 % as much as that of Pt anode, indicating that Ni3Mo3C is comparative to noble metal platinum as anode electrocatalyst for MFCs by increasing the loading.

A pure beta-molybdenum carbide (M(O2)C) with a Brunauer-Emmett-Teller (BET) special surface area of 77.5 m2/g, prepared by solution derived precursor, was used as anodic catalyst of microbial fuel cell (MFC) based on Klebsiella pneumoniae (K. pneumoniae). The electrochemical activity of the prepared M(O2)C and the performance of the MFC were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and polarization curve measurement. The results show that the prepared M(O2)C has high electrocatalytic activity and is a potential alternative to platinum as the anodic catalyst of MFCs. The maximum power density of single-cube MFC with 6.0 mg/cm2 M(O2)C as anodic catalyst is 2.39 W/m3. This power density is far higher than that of the MFC with carbon felt as anode without any catalyst (0.61 W/m3), and comparable to that of the MFC using 0.5 mg/cm2 Pt as anodic catalyst (3.64 W/m3).