Proton Conduction in Organically Templated 3D Open-Framework Vanadium–Nickel Pyrophosphate

Abstract

A new proton-conducting material (C6H14N2)­[NiV2O6H8(P2O7)2]·2H2O (1) was hydrothermally synthesized by using 1,4-diazabicyclo­[2,2,2]­octane (DABCO) as the template. Its inorganic framework, determined by single crystal X-ray diffraction, is constructed by the connection of V/NiO6 octahedral to P2O7 pyrophosphate units through sharing oxygen atoms, giving rise to three-dimensional (3D) intersecting 6-, 8-, and 12-ring channels along the [100], [010], and [001] directions, respectively, in which there are ordered protonated DABCO cations balancing negative charge of the framework and disordered water molecules. Complex impedance measurements on polycrystalline samples gave proton conductivities of 4.9 × 10–3 and 2.0 × 10–2 S cm–1 at 25 and 60 °C under high humidity conditions, respectively. The activation energy is 0.38 eV.

Proton-Conducting Vanadoborate with New [V10B26] Clusters

“…The spectral bands at 1671, 1600, and 3461–2947 cm –1 are ascribed to the bending and tensile vibrations of the N–H and O–H groups. , The charge balance of the structure was verified by BVS bond valence theory calculations (Table S4), which confirmed the presence of B­(III), Ni­(II), and V­(IV) in the crystal. In addition, the presence of V and Ni was further confirmed by an XPS analysis of compound 1 and the result of the test (Figure S4) showed that the valence state of the V ion was V 4+ and that of the Ni ion was Ni 2+ , which is consistent with reports in the literature. − Its crystallographic data are shown in Table S1.…”

Ultrahigh Proton Conduction in Two Highly Stable Ferrocenyl Carboxylate Frameworks

“…As demonstrated in Table , the highest σ of 1 is comparable to that of Nafion and several conductive materials of COF­(TfBD) (3.0 × 10 –1 S/cm, 80 °C and 95% RH), PSM 1 (1.67 × 10 –1 S/cm, 80 °C and 95% RH), MOF­(Co) (1.49 × 10 –1 S/cm, 80 °C and 98% RH), H 3 PO 4 @S1–15 (1. 37 × 10 –1 S/cm, 30 °C and 100% RH), and BUT-8­(Cr)­A (1.27 × 10 –1 S/cm, 80 °C and 100% RH) and higher than that of a few of efficient proton conducting materials with high conductivities around 10 –2 S/cm. ,,,,,− Also, the highest proton conductivity of 2 can be comparable with the above high proton conducting materials under similar testing conditions. ,,,,,− …”

A [V6B20]-based architecture incorporating two types of organic amine ligands: innovative additives for enhancing the proton conductivity of Nafion membrane

“…S1, ESI†). 33 The absorption band observed in the UV spectrum of VB-1 (Fig. S2, ESI†) indicates charge transfer within the [V 6 B 20 ] cluster unit.…”

“…S1, ESI †). 33 The absorption band observed in the UV spectrum of VB-1 (Fig. S2 34,35 The experimental PXRD pattern presented in Fig.…”