The charge transfer kinetics of the oxidation of silver and nickel nanoparticles via particle–electrode impact electrochemistry

Abstract

The electro-oxidation of silver and nickel nanoparticles in aqueous solution was studied via their collisions with a carbon electrode. The average charge passed per impact varies with electrode potential and was analysed to determine that AgNPs display an electrochemically fast ("reversible") one-electron oxidation, whilst the NiNPs exhibit slow ("irreversible") 2-electron kinetics. Kinetic parameters are reported.

Charging and discharging at the nanoscale: Fermi level equilibration of metallic nanoparticles

“…56 The simplest experiments involve direct electrochemical measurements of the NPs by raising and lowering of E NPF on impact. The majority of these studies involve oxidation (and subsequent dissolution, see Scheme 6A) of Ag, 57 Au, 58 Cu 59 or Ni 60 NPs to reveal a host of information such as the NP size distributions and conductivities, 57 identification of individual NPs in a mixture, 61 the concentrations of the NPs, 61 the NP residence time on the electrode sufficient to ensure complete oxidation, 62 etc. Bard et al demonstrated that single NP collisions with an electrode could be observed via electrocatalytic amplification.…”

Metal‐halide Nanoparticle Formation: Electrolytic and Chemical Synthesis of Mercury(I) Chloride Nanoparticles

“…This has since been applied to a range of catalysed reactions including oxygen reduction, [20] water oxidation [21] and sodium borohydride oxidation. [22] The characterisation of NPs by their direct electrolysis has also been applied to a range of NP materials including metal, [23][24][25] metal oxide, [26] organic [27] and polymeric NPs. [28] When a NP collides with the electrode, a transient spike in current is observed and the charge passed can be directly related to its size.…”

Potassium (De‐)insertion Processes in Prussian Blue Particles: Ensemble versus Single Nanoparticle Behaviour

“…Its diverse applications rangef rom K-ion batteries, [5a, b] chemical and biological sensors, [8] H 2 O 2 catalysis [9] and electrochromic devices. [11] The magnitude of the charge,d uration and frequency of an umerically relevant number of single collisione vents, leads to directi nformation regarding the reactions occurring at the nanoscale. Single nanoparticlea nalysis was performedt hrough the electrode-particlei mpact method in which particles are suspended in solutiona nd they may,b yv irtue of their Brownian motion, collide with ap otentiostated microelectrode.…”