Anti-corrosive and anti-microbial properties of nanocrystalline Ni-Ag coatings

Graphene-Reinforced Zn–Ni Alloy Composite Coating on Iron Substrates by Pulsed Reverse Electrodeposition and Its High Corrosion Resistance

“…where ρ is the density of the metal undergoing corrosion (7.87 g/cm 3 for Fe) and "0.129" is the calculation parameter. 52 Obviously, according to the CR values in Table 3, the corrosion resistance of the composite coatings was improved effectively due to the Gr incorporation. The mechanism could be explained as follows: (1) As an anode, Zn was dissolved and oxidized to Zn 2+ , which was stable thermodynamically; (2) for the pure Zn coating, the corrosion products were mainly ZnO, while for the regular Zn−Ni alloy coating, the main corrosion products consisted of ZnO, ZnCl 2 •Zn(OH) 2 and a little of 2ZnCO 3 •3Zn(OH) 2 ; 53 (3) when the regular Zn−Ni alloy coating was in a corrosive environment, Zn was first corroded and produced white rust of Zn(OH) 2 •2H 2 O, which was a non-conductive substance and tended to form a dense Zn(OH) 2 film on the coating surface as a protective layer; (5) however, in the pure Zn coating, Zn(OH) 2 •2H 2 O was easily converted into a ZnO film (a kind of n-type semiconductor) and formed a loosened film, and this film was in favor of passing through the corrosion current and weakened the shielding effect of the protective film; (6) the existence of the Ni element in the coating played a role in inhibiting the transformation from Zn(OH) 2 •2H 2 O into the ZnO film and therefore, the Zn−Ni alloy coating held a smaller corrosion current and lower CR than the pure Zn coating; (7) more importantly, the welldispersed Gr sheets in the composite coating acted as a barrier for preventing the penetration of corrosive media and further improved the corrosion resistance in corrosive environments; moreover, the best effect was acquired at the optimal GO adding content, about 0.4 g/L, in the electrolyte.…”

“…The corrosion rate (CR) ( r corr ) could be calculated from i corr by using Faraday’s law of electrolysis where M is the atomic weight of the metal (56 g/mol for Zn), Z is the number of lost electrons per metal atom during the anodic dissolution of the metal, and F is the Faraday constant (96485.34 C/mol). The r corr in this equation is the mass of dissolved metal in time per t unit area, which can be converted to corrosion depth by the following equation where ρ is the density of the metal undergoing corrosion (7.87 g/cm 3 for Fe) and “0.129” is the calculation parameter …”

Electrochemical Corrosion Resistance and Electrical Conductivity of Three-Dimensionally Interconnected Graphene-Reinforced Cu Composites

“…In corrosion kinetics, the corrosion rate (CR) is directly proportional to I corr ; hence, a higher I corr value would lead to a higher CR. Faraday's law of electrolysis was employed to deduce the CR from the value of I corr using the following equation [34]:…”

Cu/Ni/Au multilayers by electrochemistry: A crucial system in electronics - A critical review

“…those that can be deposited individually and those that can be only codeposited. The former group consists of metals that are much nobler than Ni, like Ag [54][55][56][57] and Cu [58][59][60][61][62][63][64][65][66][67][68]; metals that have similar standard potentials, such as Co [69][70][71][72][73][74][75][76] and Sn [77][78][79][80][81][82][83][84][85]; and metals that are more cathodic, like Cr [86,87], Zn [88][89][90][91][92][93][94][95][96][97][98][99][100] and Mn [101]…”