Sa Liu,Li Zhou,Pengjie Wang,Linsong Zhang,Zhigang Shao,Baolian Yi
A new blend ultrafiltration (UF)/nanofiltration (NF)-based proton-conductive membrane, which comprised poly(ether sulfone) (PES), sulfonated poly(ether ether ketone) (SPEEK) and absorbed aqueous acid, as an alternative to traditional exchange membrane, was proposed and designed for H2/Cl2 fuel cells. The effect of SPEEK concentration at different degree of sulfonation on membrane properties was systematically studied. The room-temperature conductivity of the prepared membrane doped with 3 M hydrochloric acid reached up to 106–131 mS cm−1. The electrochemical characteristics of membrane/electrode assemblies using the PES–SPEEK composite membrane were also analyzed. The cell exhibited better performance than that of a cell based on Nafion 212 membrane (about twice). The study provides an effective way to fabricate high performance porous membranes for H2/Cl2 fuel cell applications.
Chun-Chao Hou,Ting-Ting Li,Shuang Cao,Yong Chen,Wen-Fu Fu
A molecular photosensitizer [Ru(dcbpy)(bpy)2]2+ (dcbpy = 2,2′-bipyridyl-5,5′-dicarboxylic acid) and a proton reduction catalyst Pt(dcbpy)Cl2 were successfully incorporated into a highly robust metal–organic framework (MOF) of Zr(IV)6O4(OH)4(bpdc)6 (bpdc = 4,4′-biphenyldicarboxylic acid) by making use of a mix-and-match approach. The molecular integrity of the Ru and Pt complexes within the MOFs was demonstrated by a variety of techniques, including XRD, BET, TGA, SEM, TEM, HAADF-STEM, EDX, DRUS and XPS. This di-component Ru–Pt@UIO-67 MOF assembly allows a facile arrangement of the photosensitizer and the reduction catalyst with close spatial proximity, promotes the electron transfer between them, and thus leads to a significantly improved hydrogen evolution activity in aqueous solution at pH 5.0 upon visible light irradiation. This Ru–Pt@UIO-67 system represents the first example of MOFs functionalized with two different transition metal complexes, which can be used as a photosensitizer and catalyst, respectively, for hydrogen generation from water.
Introduction of divalent metal oxides into the TeO2 matrix can produce the chemical formula Mn[TemO2m+n] ≡ (MO)n(TeO2)m, compounds in which divalent metal oxides provide oxygen ions to the parent compound TeO2, to cleave neutral Te–O net to form various tellurium(IV) oxide anion [TemO2m+n]2n− and divalent metal cations as balanced charges. [TemO2m+n]2n− can form isolated anion, discrete polyanion, one-dimensional chain and ribbon polyanion, two-dimensional (2D) layered polyanion, and 3D tunnel polyanion depending on the ratio of MO/TeO2. In this work, a new type of inorganic compound AE2[Ni(Te4O10)Cl2] ≡ [(AEO)2(TeO2)4](NiCl2) (AE = Ca, Sr, Ba, Pb) can be obtained by introducing NiCl2 into the compound AE2[Te4O10] ≡ (AEO)2(TeO2)4 (AE = Ca, Sr, Ba, Pb). In AE2[Ni(Te4O10)Cl2] ≡ [(AEO)2(TeO2)4](NiCl2), AEO acts as a structural shearing agent to cleave the neutral Te–O layered structures of parent TeO2 into [Te4O10]4– anionic fragments, and the introduced NiCl2 acts as an “adhesive” to recombine [TemO2m+n]2n− anionic fragments to form new [Ni(Te4O10)Cl2] anionic framework and does not provide additional oxygen ions to cleave the parent compound TeO2. AE2[Ni(Te4O10)Cl2] compounds feature 2D 2∞[Ni(Te4O10)Cl2] anionic layers composed by TeO4E, TeO3+1E (where E is the lone pair of electrons of TeIV) distorted trigonal bipyramid, and NiO4Cl2 octahedra, and the spaces between 2∞[Ni(Te4O10)Cl2] layers are filled with AE2+ cations (acting as charge balance) as well as E (protruding from sides of the layers). The optical band gaps of AE2[Ni(Te4O10)Cl2] (AE = Ca, Sr, Ba, Pb) were evaluated to be ∼3.69 eV through extrapolating the UV–vis–near-infrared optical absorption spectra. Thermogravimetric and differential scanning calorimetry measurements indicate that Ca-, Sr-, Ba-, and Pb-compounds are stable below 787, 716, 648, and 517 °C, respectively, under flowing N2 atmosphere. The effective moments estimated by Curie–Weiss equation show that the Ni2+ cations of AE2[Ni(Te4O10)Cl2] (AE = Ca, Sr, Ba, Pb) are all in high-spin ground states.
危险品化学品经营许可证（带存储）