Electrochemical sorption of hydrogen in exfoliated graphite/nickel/palladium composite

Methanol Electrooxidation at Electrodes Made of Exfoliated Graphite/Nickel/Palladium Composite

“…Such a behavior indicates that during the second and third cycle the regarded cathodic peaks are likely associated with reduction of Pd oxides formed on the surface of electrode during the previously performed anodic oxidation [15,19]. For the first cycle, during the anodic polarization, presented curve involves anodic wave with two maxima positioned at − 0.602 and − 0.49 V. These effects can be assigned to oxidation of Ni particles [7,15,[22][23][24][25]30]. During the second and third cycle the location of these peaks vary due to activation of Ni.…”

“…The investigated EG/Ni/Pd composite was widely described in our previous work [30]. On the basis of XRD analysis two essential conclusions have been stated.…”

“…Our work reported that exfoliated graphite/nickel/palladium (EG/Ni/Pd) composite exhibits high electrochemical activity toward the processes of reversible electrosorption of hydrogen [30]. Electrochemical measurements comprising of cyclic potential scanning interrupted by the potentiostatic saturation of composite electrode with hydrogen provided an important information on the mechanism of hydrogen accumulation within the respective parts of the examined composite.…”

Electrochemical properties of exfoliated graphite/nickel/palladium/carbon fibers composite

“…Firstly, exfoliated graphite (EG) was coated with a layer of Ni by electrochemical treatment in bath composed of NiSO 4 x7H 2 O (140 g dm −3 ), NiCl 2 x 6H 2 O (5 g dm −3 ), and H 3 BO 3 (20 g dm −3 ) using a constant current density of 20 mA g −1 . As prepared EG/Ni underwent chemical reaction in 0.11 M PdCl 2 dissolved in 1 M HCl to yield EG/Ni/Pd [3]. A carbon layer of EG/Ni/ Pd/C composite was formed by thermal decomposition of acetylene by CVD method (chemical vapor deposition).…”

“…Our previous works revealed that graphite intercalation compound with nickel chloride (NiCl 2 -GIC) and with nickel chloride, iron chloride, and palladium chloride (NiCl 2 -FeCl 3 -PdCl 2 -GIC) are electrochemically active towards the processes of hydrogen sorption/desorption [1,2]. The composite described in our last paper concerning the electrochemical properties of EG/Ni/Pd has a markedly different structure [3]. The sandwich type structure makes it more accessible to electrolytes, thus contributing to the increment in activity of reversible sorption of hydrogen.…”