Electrical conductivity of boron orthophosphate in presence of water

Mikhailenko, Serguei D.; Zaidi, Javaid S. M.; Kaliaguine, Serge

doi:10.1039/a708622i

Cited by 48 publications

(24 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The resonance at approximately À7 ppm is assigned to anhydride formation between two phosphoric acid molecules [36], which can still contribute to the conductivity via the vehicle mechanism. The other signals appearing at lower chemical shift values are most likely due to the possible anhydride formation between phosphoric acid molecules and boron sites (B-O-P arrangements) [21,37]. The formation of similar chemical structures has been studied before, in particular in the case of boron-phosphate glasses, where high-field shifts of 10-20 ppm of 31 P sites involved in the B-O-P links have been observed [40].…”

Section: Solid-state Nmr Studiesmentioning

confidence: 95%

“…The adsorbed water is present in a partially dissociated form because the surface is also covered with hydroxyl groups of various types, i.e., free B-OH, P-OH, geminal P-OH and H-bonded OH groups associated with both B and P. BPO 4 acts as a proton conductor probably due to the presence of the above-mentioned protogenic groups on the surface [20]. The conductivity of BPO 4 increased with atomic ratio of B/P and reached to a maximum value when B/P ratio is 0.80 [21].…”

Section: Introductionmentioning

confidence: 94%

See 1 more Smart Citation

Synthesis and NMR studies of the polymer membranes based on poly(4-vinylbenzylboronic acid) and phosphoric acid

Sezgin

Akbey

Hansen

et al. 2008

Polymer

View full text Add to dashboard Cite

Section: Solid-state Nmr Studiesmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 94%

Synthesis and NMR studies of the polymer membranes based on poly(4-vinylbenzylboronic acid) and phosphoric acid

Sezgin

Akbey

Hansen

et al. 2008

Polymer

View full text Add to dashboard Cite

“…By introducing metal oxides of high surface area, inorganic composites of CsHSO 4 129 It has been suggested to prepare composite membranes for the fuel cell purpose. 130 Recently a high-proton-conducting salt, boron phosphate (BPO 4 ), has been prepared 131 and its stability has been improved by aluminum substitution. 132 …”

Section: Inorganic Solid Proton Conductorsmentioning

confidence: 99%

Approaches and Recent Development of Polymer Electrolyte Membranes for Fuel Cells Operating above 100 °C

et al. 2003

View full text Add to dashboard Cite

The state-of-the-art of polymer electrolyte membrane fuel cell (PEMFC) technology is based on perfluorosulfonic acid (PFSA) polymer membranes operating at a typical temperature of 80°C. Some of the key issues and shortcomings of the PFSA-based PEMFC technology are briefly discussed. These include water management, CO poisoning, hydrogen, reformate and methanol as fuels, cooling, and heat recovery. As a means to solve these shortcomings, hightemperature polymer electrolyte membranes for operation above 100°C are under active development. This treatise is devoted to a review of the area encompassing modified PFSA membranes, alternative sulfonated polymer and their composite membranes, and acidbase complex membranes. PFSA membranes have been modified by swelling with nonvolatile solvents and preparing composites with hydrophilic oxides and solid proton conductors. DMFC and H 2 /O 2 (air) cells based on modified PFSA membranes have been successfully operated at temperatures up to 120°C under ambient pressure and up to 150°C under 3-5 atm. Alternative polymers are selected from silicon-and fluorine-containing inorganic polymers or aromatic hydrocarbon polymers and functionalized by sulfonation. The sulfonated hydrocarbons and their inorganic composites are potentially promising for high-temperature operation. High conductivities have been obtained at temperatures up to 180°C. Acid-base complex membranes constitute another class of electrolyte membranes. A high-temperature PEMFC based on H 3 PO 4 -doped PBI has been demonstrated for operation at temperatures up to 200°C under ambient pressure. The advanced features include high CO tolerance, simple thermal and water management, and possible integration with the fuel processing unit.

show abstract

“…5 shows the FT-IR spectra of the pure SPES and the composite membranes containing 10-40 vol.% SnP-NS. In the FT-IR spectra, peaks assigned to symmetric SO 3 − stretching vibrations appeared at 1022 cm −1 for the pure SPES membrane and the peak shifted to higher wavenumbers by the addition of SnP to the SPES matrix [31,32]. Fig.…”

Section: Resultsmentioning

confidence: 99%

Effects of tin phosphate nanosheet addition on proton-conducting properties of sulfonated poly(ether sulfone) membranes

et al. 2012

View full text Add to dashboard Cite

a b s t r a c t a r t i c l e i n f oThe stabilities and proton conductivities of SPES/SnP nanosheet (SnP-NS) composite membranes were investigated and compared with those of SPES/SnP particle (SnP-P) composite membranes. The chemical stabilities as evaluated by thermogravimetry, differential thermal analysis, and diffuse reflectance Fourier-transform infrared spectroscopy were improved in both composite membranes. The improvement in the structural stability of SPES/SnP-NS composite membranes was more evident than that in SPES/SnP-P. The results suggest that exfoliation of SnP increases the area of the SPES-SnP interface and extends the connectivity of the network of hydrogen bonds. A composite membrane containing 10 vol.% SnP-NS (SPES/SnP-NS10vol.%) showed a high conductivity of 5.9×10−2 S cmat 150°C under saturated water vapor pressure. Although less water was present in SPES/SnP-NS10vol.% than in SPES/SnP-P10vol.% or pure SPES, the conductivity of SnP-NS10vol.% was the highest among these samples at 130°C under a high relative humidity (RH). However at a low RH, the proton-conducting property was not improved by changing the composition of the SnP-NS. These results suggest that the hydrogen-bond network operates effectively for proton conduction at a high RH, but at a low RH, the network fails to conduct as a result of a decrease in water content accompanied by structural stabilization.

show abstract

Electrical conductivity of boron orthophosphate in presence of water

Cited by 48 publications

References 3 publications

Synthesis and NMR studies of the polymer membranes based on poly(4-vinylbenzylboronic acid) and phosphoric acid

Synthesis and NMR studies of the polymer membranes based on poly(4-vinylbenzylboronic acid) and phosphoric acid

Approaches and Recent Development of Polymer Electrolyte Membranes for Fuel Cells Operating above 100 °C

Effects of tin phosphate nanosheet addition on proton-conducting properties of sulfonated poly(ether sulfone) membranes

Contact Info

Product

Resources

About