16871-54-8Relevant articles and documents
Elding, L. I.,Gustafson, L.
, p. 31 - 38 (1976)
New strategy to prepare platinum salts by electrochemical methods and subsequent synthesis of platinum nanoparticles
Mai, Fu-Der,Yu, Chung-Chin,Liu, Yu-Chuan,Hsu, Ting-Chu,Wu, Yi-Hao
, p. 167 - 171 (2012)
As shown in the literature, most of Pt nanoparticles (NPs) were synthesized from precursors of commercial Pt salts. However, the impurity of the commercial Pt salts is a concerned issue. In this work, we report a new pathway based on electrochemical methods to prepare Pt-containing complexes with high purity in aqueous solutions from bulk Pt substrates. Experimental results indicate that Pt complexes with higher concentration can be obtained in 0.1 N HCl by using square-wave oxidation-reduction cycles (ORCs) under a frequency of 8 Hz with a step potential of 6.3 mV. Moreover, concentrations of other heavy metals of Hg and Cr in 65 ppm Pt complexes-containing solution are just 0.65 and 0.78 ppb, respectively. These Pt complexes were further reduced to Pt NPs by using NaBH4 and poly(vinylpyrrolidone) (PVP) as reducing agent and stabilizer, respectively. The concentration and the particle size of synthesized Pt (1 1 1) NPs are ca. 60 ppm and smaller than 5 nm, respectively.
Mechanism of tetrachloroplatinate(ii) oxidation by hydrogen peroxide in hydrochloric acid solution
Murray, Pieter,Koch, Klaus R.,Van Eldik, Rudi
, p. 6308 - 6314 (2014/04/17)
Oxidation of tetrachloroplatinate(ii) by hydrogen peroxide in hydrochloric acid was studied by UV-Vis spectrophotometry. Oxidation takes place via two parallel reactions with hypochlorous acid and hydrogen peroxide, respectively, according to the overall rate law d[Pt(iv)]/dt = (k0 + k H2O2[Pt(ii)])[H2O2]. For oxidation of [PtCl4]2- at relatively low concentrations, [PtCl4]2- ? 0.5 mM, hypochlorous acid formation is fast relative to the oxidation of [PtCl4]2- by hydrogen peroxide, as a result of the rate determining reaction H2O 2 + H+ + Cl- → HOCl + H2O, resulting in a rate law d[Pt(iv)]/dt = k0[H2O2] with a value k0 = (8 ± 2) × 10-7 s -1 at 35 °C. For concentrations of [PtCl4] 2- > 0.5 mM, oxidation by hydrogen peroxide becomes dominant, resulting in the pseudo-first order rate law d[Pt(iv)]/dt = kH2 O2[Pt(ii)][H2O2] with the value kH2O2 = (1.5 ± 0.1) × 10 -2 M-1 s-1 at 35°C. The final oxidation product is a mixture of [PtCl5(H2O)]- and [PtCl6]2-, with [PtCl6]2- formed as a result of [PtCl4]2- assisted chloride anation reactions. This journal is the Partner Organisations 2014.
Outer-sphere electron transfer from platinum(II) to Keggin-type 12-tungstocobaltate(III) in the presence and absence of chloride ions
Bhosale,Gokavi
, p. 799 - 802 (2007/10/03)
The reaction between Pt(II) and [CoIIIW12I 40]5- proceeds with two, one-electron steps involving formation of unstable Pt(III) followed by its reaction with another oxidant. The reaction rate is unaffected by the [H+] as there are no protonation equlibria involved with both the reactants whereas, chloride ion accelerates the reaction and the reaction follows chloride independent and dependent paths leading to a two term rate law, rate= {k1 + Kk 2 [Cl-]} [Pt(II)] [CoIIIW12O 40]5-. The chloride ion dependent path is due to rapid substitution of chloride ion on PtCl42-. The products formed have been found to be PtCl4(aq) and PtC6 2- in the absence and presence of chloride ion respectively. Increase in the ionic strength and decrease in the relative permittivity of the medium increase the rate of the reaction. This is due to the formation of an outer-sphere complex between the two reactants. The activation parameters in the presence and absence of chloride ions have also been determined and the values support the proposed mechanism.
