High specific surface area carbon aerogel derived from starch for methylene blue adsorption and supercapacitors.

Starch based carbon aerogel has attracted significant attention due to the wide source, environmental friendliness and low price of raw materials. Here, starch based carbon aerogel was fabricated by graft reaction and cross-linking reaction of starch. The network structure of starch hydrogel was optimized through graft and cross-linking reaction.

A completely precious metal-free alkaline fuel cell with enhanced performance using a carbon-coated nickel anode.

SignificanceWe present a groundbreaking advance in completely nonprecious hydrogen fuel cell technologies achieving a record power density of 200 mW/cm with Ni@CN anode and Co-Mn cathode. The 2-nm CN coating weakens the O-binding energy, which effectively mitigates the undesirable surface oxidation during hydrogen oxidation reaction (HOR) polarization, leading to a stable fuel cell operation for Ni@CN over 100 h at 200 mA/cm, superior to a Ni nanoparticle counterpart. Ni@CNx exhibited a dramatically enhanced tolerance to CO relative to Pt/C, enabling the use of hydrogen gas with trace amounts of CO, critical for practical applications.

[Expression of Twist1, SIRT1, FGF2 and TGF-β3 genes and its regulatory effect on the proliferation of placenta, umbilical cord and dental pulp mesenchymal stem cells].

Objective: To compare the mRNA level of cell proliferation-related genes Twist1, SIRT1, FGF2 and TGF-β3 in placenta mesenchymal stem cells (PA-MSCs), umbilical cord mensenchymals (UC-MSCs) and dental pulp mesenchymal stem cells (DP-MSCs).

Methods: The morphology of various passages of PA-MSCs, UC-MSCs and DP-MSCs were observed by microscopy. Proliferation and promoting ability of the three cell lines were detected with the MTT method.

Improving the Antioxidation Capability of the Ni Catalyst by Carbon Shell Coating for Alkaline Hydrogen Oxidation Reaction.

Increasing the antioxidation capability of Ni for the hydrogen oxidation reaction (HOR) is considered important and challenging for alkaline polymer electrolyte fuel cells (APEFCs). Herein, we report a series of Ni-core carbon-shell (Ni@C) catalysts obtained by a vacuum pyrolysis method treated at different temperatures. According to the cyclic voltammetry tests and the HOR tests, Ni@C treated at 500 °C exhibits a much higher Ni core utilization and better catalytic activity toward HOR than the commonly used Ni/C catalyst.

The Comparability of Pt to Pt-Ru in Catalyzing the Hydrogen Oxidation Reaction for Alkaline Polymer Electrolyte Fuel Cells Operated at 80 °C.

The Pt-catalyzed hydrogen oxidation reaction (HOR) for alkaline polymer electrolyte fuel cells (APEFCs) has been one of the focus subjects in current fuel-cell research. The Pt catalyst is inferior for HOR in alkaline solutions, and alloying with Ru is an effective promotion strategy. APEFCs with Pt-Ru anodes have provided a performance benchmark over 1 W cm at 60 °C.

Sulfonated Nanobamboo Fiber-Reinforced Quaternary Ammonia Poly(ether ether ketone) Membranes for Alkaline Polymer Electrolyte Fuel Cells.

Alkaline polymer electrolyte fuel cells (APEFCs) are a new class of electrochemical devices that intrinsically enable the use of nonprecious metal catalysts. As an important component of APEFCs, alkaline polymer electrolytes (APEs) have been a research focus in recent decades. To minimize the ohmic loss and to facilitate the water transport, the APE membrane should be as thin as possible, which generally requires a trade-off between the ionic conductivity and the mechanical robustness/dimensional stability of the membrane.

An effective approach for alleviating cation-induced backbone degradation in aromatic ether-based alkaline polymer electrolytes.

Aromatic ether-based alkaline polymer electrolytes (APEs) are one of the most popular types of APEs being used in fuel cells. However, recent studies have demonstrated that upon being grafted by proximal cations some polar groups in the backbone of such APEs can be attacked by OH(-), leading to backbone degradation in an alkaline environment. To resolve this issue, we performed a systematic study on six APEs.

Facile bottom-up synthesis of coronene-based 3-fold symmetrical and highly substituted nanographenes from simple aromatics.

A facile and efficient self-sorting assemble (CSA) strategy has been paved for bottom-up construction of the 3-fold symmetrical and highly substituted hexa-cata-hexabenzocoronenes (c-HBCs), the trithieno analogues, and larger disc-shaped PAHs from simple chemicals using benzylic carbons as tenon joints and a novel FeCl3-mediated AAA process as a key step. The structures of the as-prepared c-HBCs and related NGs were clearly identified by spectral analyses and X-ray crystallographic studies. Moreover, these can be envisaged to serve as new launching platforms for the construction of larger and more complex π-conjugated molecules and supramolecular architectures because of the modifiable and symmetrical decorations.

Highly stable alkaline polymer electrolyte based on a poly(ether ether ketone) backbone.

Alkaline polymer electrolyte fuel cells (APEFCs) promise the use of nonprecious metal catalysts and thus have attracted much research attention in the recent decade. Among the challenges of developing practical APEFC technology, the chemical stability of alkaline polymer electrolytes (APEs) seems to be rather difficult. Research found that, upon attachment of a cationic functional group, an originally stable polymer backbone, such as polysulfone (PSF), would degrade in an alkaline environment.