Proton Conductive Lanthanide-Based Metal–Organic Frameworks: Synthesis Strategies, Structural Features, and Recent Progress

High Protonic Conductivity of Three Highly Stable Nanoscale Hafnium(IV) Metal–Organic Frameworks and Their Imidazole-Loaded Products

“…To clarify the proton-conducting mechanism, the E a values of 1–3 were calculated by the Arrhenius eq . As for 1 , E a values are 0.92 and 0.47 eV at 68 and 98% RHs, respectively (Figure j), implying that the proton conduction belongs to the Vehicle mechanism (>0.40 eV) ,− at 68% RH and hybrid mechanism, which is mainly governed by the Vehicle mechanism, combined with the synergic Grotthuss mechanism at 98% RH. − At low humidity, the additional protons diffuse directly with the water molecules, and the movement of protons depends mainly on proton hopping along with H-bonded networks at high humidity. For 2 , at 68% RH, there exist diverse mechanisms at different temperature ranges, which are 1.83 eV (40–70 °C) and 0.41 eV (80–100 °C) (Figure k), revealing that proton conduction of 2 corresponds to the Vehicle mechanism at low temperature ranges and hybrid mechanism at high-temperature ranges.…”

“…The excellent structural stability as well as the durability and stability of their proton conduction demonstrate that these MOFs have great potential in the proton conduction field. 59,68 In addition, the proton conductivities of Im@1,2,3 under anhydrous conditions were tested and the results showed that σ increased with the increase of temperature, reaching the maximum value at 160 °C (1.53 × 10 −6 for Im@1; 2.41 × 10 −6 for Im@2; and 2.29 × 10 −5 S•cm −1 for Im@3) (Figure S17). Because the proton conductivities of these three compounds are almost negligible in anhydrous conditions, we mainly focus on their proton conductivities in humid environments.…”

“…As shown in Figure S15, under such test conditions, their proton conductivity hardly changes within 10 h. Furthermore, comparing the PXRD patterns of the samples before and after the AC impedance test, it is found that the structure of the samples remains intact (Figure S16). The excellent structural stability as well as the durability and stability of their proton conduction demonstrate that these MOFs have great potential in the proton conduction field. , …”

Two Stable Cd-MOFs as Dual-Functional Materials with Luminescent Sensing of Antibiotics and Proton Conduction

“…8,32,36 To date, although many MOF-based proton-conducting materials have been reported and exhibited relatively good conductivity, only a few examples exhibited outstanding physical and chemical stabilities. 18,32,34,36,37 Therefore, designing multifunctional MOFs exhibiting excellent physical and chemical stabilities and promising proton conduction and luminescent sensing performances is very important and highly desirable to meet the requirement of practical applications.…”

Rational design of heterostructural heterometallic phosphonates as highly efficient electrocatalysts for overall water splitting under alkaline conditions

“…They have many potential applications in the fields of gas storage/separation, sensing, optics, biomedicine and catalysis. 5,24–27 In recent years, more and more work has confirmed that transition metal based MOF materials are promising electrocatalysts for water splitting. For instance, Liu and his coworkers reported that a 2D CoNi-MOF array is a superior OER electrocatalyst in alkaline medium, showing a low overpotential of 265 mV at 10 mA cm −2 .…”