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PtZn is Tetraauricupride structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Pt2- is bonded in a distorted body-centered cubic geometry to eight equivalent Zn2+ atoms. All Pt–Zn bond lengths are 2.70 Å. Zn2+ is bonded in a body-centered cubic geometry to eight equivalent Pt2- atoms.
PtZn(CN)4 crystallizes in the tetragonal P4_2/mcm space group. The structure is three-dimensional. Pt2+ is bonded in a square co-planar geometry to four equivalent C2+ atoms. All Pt–C bond lengths are 1.98 Å. Zn2+ is bonded in a tetrahedral geometry to four equivalent N3- atoms. All Zn–N bond lengths are 1.97 Å. C2+ is bonded in a single-bond geometry to one Pt2+ and one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a linear geometry to one Zn2+ and one C2+ atom.
La3(PtZn)4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded to six Pt atoms to form edge-sharing LaPt6 octahedra. There are four shorter (3.09 Å) and two longer (3.15 Å) La–Pt bond lengths. In the second La site, La is bonded in a 12-coordinate geometry to six Pt and six equivalent Zn atoms. There are two shorter (3.06 Å) and four longer (3.17 Å) La–Pt bond lengths. There are four shorter (3.19 Å) and two longer (3.22 Å) La–Zn bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to three La and six equivalent Zn atoms. There are four shorter (2.63 Å) and two longer (2.81 Å) Pt–Zn bond lengths. In the second Pt site, Pt is bonded in a 8-coordinate geometry to six La and two equivalent Zn atoms. Both Pt–Zn bond lengths are 2.65 Å. Zn is bonded in a 4-coordinate geometry to three equivalent La and four Pt atoms.
Preactivated MFI zeolite nanosheet plates (ZNPs) with large areas (~2.0 × 2.0 μm 2 ) and nanometer thicknesses (~60 nm) were prepared directly in liquid-dispersed state. The individual ZNP was a stack of 4-nm-thick single crystalline zeolite nanosheets (ZNs) interlinked by Si–O–Si bonds between neighboring ZN surfaces. The dispersed open-pore ZNPs allowed formulating suspensions for tiling ZNP membranes on polymer substrates without requiring post-coating activation. A pinhole-free ZNP-tiled (ZNPT) membrane has been achieved on macroporous PVDF film by a self-repairing vacuum-assisted filtration coating method. The resultant ZNPT layer was ~500 nm-thick consisting of about 7 ZNP layers with inter-ZNP width and inter-ZNP entrance porosity around 9 nm and 2%, respectively. The ZNPT-PVDF membrane exhibited high selectivity to proton transport over vanadyl ion and low resistances to proton conduction in aqueous solutions. The membrane also demonstrated to function as an efficient ion separator for the vanadium redox flow battery. The reported synthesis of preactivated ZNP suspension may overcome the major hurdle to realizing polymer-supported ZN membranes, which is the inefficiency of existing methods in obtaining readily dispersible open-pore ZNs. Finally, the ZNPT-PVDF membrane can be a more affordable and sustainable alternative to the Nafion-based ion separation membranes.