نتایج جستجو برای: proton conductivity
تعداد نتایج: 115521 فیلتر نتایج به سال:
HKUST-1, a metal-organic framework (MOF) material containing Cu(II)-paddlewheel-type nodes and 1,3,5-benzenetricarboxylate struts, features accessible Cu(II) sites to which solvent or other desired molecules can be intentionally coordinated. As part of a broader investigation of ionic conductivity in MOFs, we unexpectedly observed substantial proton conductivity with the "as synthesized" versio...
Various polybenzimidazole (PBI)-based ion-exchange films were prepared and thoroughly characterized by Fourier transform infrared (FT-IR) spectroscopy, proton conductivity, and water uptake for possible use as fuel cell membranes. Upon the increase in the flexibility of the PBI-based polymer films (e.g., poly(oxyphenylene benzimidazole) (OPBI) and sulfonated OPBI (s-OPBI)), the membranes exhibi...
Polymer-electrolyte-membrane fuel cells (PEM-FCs) are considered as the most promising fuel cell technique for applications like automobiles or stationary power supplies. State-of-the-art separator materials in PEM-FCs are commonly sulfonic acid functionalized polymers, like the perfluorinated polymer Nafion. These materials show the required high proton conductivity only at high degree of hydr...
The introduction of sulfonic acid modified silica in Nafion nanocomposite membranes is a good method of improving the Nafion performance at high temperature and low relative humidity. Sulfonic acid-modified silica is bifunctional, with silica phase expected to offer an improvement in membranes hydration while sulfonic groups enhance proton conductivity. However, as discussed in this paper, this...
Proton transport is critical for many technologies and a variety of biochemical biophysical processes. transfer between molecules (via structural diffusion) considered to be an efficient mechanism in highly proton conducting materials. Yet, the what controls energy barriers this process remain poorly understood. It was shown that mixing phosphoric acid (PA) with lidocaine leads increase conduct...
A novel proton exchange membrane using phosphotungstic acid (HPW) as proton carrier and cubic bicontinuous Ia3d mesoporous silica (meso-silica) as framework material is successfully developed as proton exchange membranes for fuel cells. Meso-silica is functionalized by 80wt% HPW using a vacuum impregnation method. The HPW-functionalized meso-silica (HPW-meso-silica) nanocomposites are character...
Fuel cells hold great promise for wide applications in portable, residential, and large-scale power supplies. For low temperature fuel cells, such as the proton exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs), proton-exchange membranes (PEMs) are a key component determining the fuel cells performance. PEMs with high proton conductivity under anhydrous conditions can...
The novel oriented electrospun nanofiber membrane composed of MOFs and SPPESK has been synthesized for proton exchange membrane fuel cell operating at high temperature and anhydrous conditions. It is clear that the oriented nanofiber membrane displays the higher proton conductivity than that of the disordered nanofiber membrane or the membrane prepared by conventional solvent-casting method (wi...
This study describes the preparation of a novel proton conducting membranes based on bacterial cellulose (BC) modified by grafting of 2-acrylamido-2-methyl-1 -propanesulfonic acid (AMPS) through UV-induced graft polymerization. These AMPS-g-BC membranes have been characterized by various techniques including FTIR, SEM and TGA, to find their successful grafting of AMPS on BC, surface morphology ...
A new approach to enhancing proton conductivity of ceramics is demonstrated by aligning proton conductive pathways and eliminating resistive grain boundaries. Hydroxyapatite (HAP) membranes are synthesized by multistage crystallization onto palladium. The synthesis involves three steps: electrochemical deposition of HAP seeds, secondary hydrothermal crystallization onto the seed layer to promot...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید