Modification of Electrical Response after Intercalation of TTF in Vanadyl and Uranyl Phosphates

Pozas-Tormo, R.; Moreno-Real, L.; Bruque, S.; Martı́nez-Lara, M.; Ramos-Barrado, J.R.

doi:10.4028/www.scientific.net/msf.91-93.511

Cited by 9 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A compound with formula VOPO 4 Á0.25(tetrathiafulvalene)ÁH 2 O was prepared by a 15-day's reaction of an acetone solution of tetrathiafulvalene with vanadyl phosphate dihydrate at room temperature [139]. The supposed layered structure has not been confirmed by XRD.…”

Section: Intercalation Of Heterocyclic N-and S-donorsmentioning

confidence: 99%

Intercalation chemistry of layered vanadyl phosphate: a review

Beneš

Melánová

Svoboda

et al. 2012

J Incl Phenom Macrocycl Chem

View full text Add to dashboard Cite

The intercalation chemistry of layered a I modification of vanadyl phosphate and vanadyl phosphate dihydrate is reviewed. The focus is on neutral molecular guests and on metal cations used as guest species. The basic condition for the ability of the neutral molecules to be intercalated into vanadyl phosphate is a presence of an electron donor atom in them. The most commonly used guest compounds are those containing oxygen, nitrogen or sulfur as electron donor atoms. Regarding the molecules containing oxygen, various compounds were used as molecular guests starting from water to alcohols, ethers, aldehydes, ketones, carboxylic acids, lactones, and esters. An arrangement of the guest molecules in the interlayer space is discussed in connection with the data obtained by powder X-ray diffraction, thermogravimetry, IR and Raman spectroscopies, and solid-state NMR. In some cases, the local structure was suggested on the basis of quantum chemical calculations. Besides of those O-donor guests, also N-donor guests such as amines, nitriles and nitrogenous heterocycles and S-donor guests such as tetrathiafulvalene were intercalated into VOPO 4 . Also intercalates of complexes like ferrocene were prepared. Intercalation of cations is accompanied by a reduction of vanadium(V) to vanadium(IV). In this kind of intercalation reactions, an iodide of the intercalated cation is often used as it serves both as a mild reduction agent and as a source of the intercalated species. Intercalates of alkali metals, hydronium and ammonium were prepared and characterized. In the case of lithium and sodium intercalates, a staging phenomenon was observed. These redox intercalated vanadyl phosphates undergo ion exchange reactions which are discussed from the point of the nature of cations involved in the exchange. Vanadyl phosphates in which a part of vanadium atom is replaced by other metals are also briefly reviewed.

show abstract

Section: Intercalation Of Heterocyclic N-and S-donorsmentioning

confidence: 99%

Intercalation chemistry of layered vanadyl phosphate: a review

Beneš

Melánová

Svoboda

et al. 2012

J Incl Phenom Macrocycl Chem

View full text Add to dashboard Cite

show abstract

“…While various articles have appeared concerning the electrical properties of intercalated VOPO 4 , − very little work has been devoted to the electrical properties of VOPO 4 in its anhydrous and hydrated form. In the range 400−500 °C, anhydrous VOPO 4 phases were found to be extrinsic n-type semiconductors .…”

Section: Introductionmentioning

confidence: 99%

Electrical-Transport Properties of Hydrated and Anhydrous Vanadyl Phosphate in the Temperature Range 20−200 °C

Zima¹,

Vlček²,

Beneš³

et al. 1996

Chem. Mater.

View full text Add to dashboard Cite

The ac/dc conductivity of hydrated and anhydrous vanadyl phosphate has been measured in the range 20-200°C in wet and dry nitrogen. Emf and thermoelectric power measurements have also been carried out at room temperature and 180°C, respectively. At 20°C and 58% relative humidity, the ac conductivity of a pellet of VOPO 4 ‚2H 2 O is of the order 10 -5 S cm -1 . Both conductivity and emf measurements indicate that at room temperature VOPO 4 ‚2H 2 O is a mixed protonic-electronic conductor with dominant protonic component (t H + ≈ 0.9). The presence of mixed conduction has allowed to use VOPO 4 ‚2H 2 O as an electrode able to exchange reversibly protons with a solid-state protonic conductor. Proton conduction in hydrated vanadyl phosphate decreases with increasing temperature, due to the loss of intercalated water, and vanishes at 70°C concomitantly with the formation of VOPO 4 ‚H 2 O. The activation energy for electronic conduction of anhydrous VOPO 4 in a dry nitrogen atmosphere is 11.9 kcal/mol between 100 and 200°C. In this temperature range the electronic conductivity is enhanced by the presence of water chemisorbed on surface sites. Possible mechanisms accounting for this effect are suggested.

show abstract

“…Aliphatic alcohols and diols [2][3][4], amines [5], carboxylic acids [6], carboxamides [7], aliphatic nitriles [8] belong to the compounds, which can be intercalated in such a way. Great attention was devoted to the intercalation of heterocyclic N-and Sdonors [9][10][11][12][13]. Recently, intercalation of ketones [14,15], aldehydes [16], poly(ethylene glycol)s [17,18], heterocycles with O-donor [18][19][20], and g-butyrolactone [21] into vanadyl phosphate has been described.…”

Section: Introductionmentioning

confidence: 99%