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

Abstract

Mercury(I) chloride (Hg2Cl2) nanoparticles (NPs) are synthesised for the first time by using two different techniques. First, particles are formed by implosion of a calomel nanolayer, induced by partial electrolysis at a mercury hemisphere microelectrode. The resulting NPs are then characterised by the nanoimpact method, demonstrating the first time metal chloride NPs have been sized by this technique and showing the ability to form and study NPs in situ. Second, Hg2Cl2 NPs are synthesised by using the precipitation reaction of Hg2(NO3)2 with KCl. The NPs are characterised on both mercury and carbon microelectrodes and their size is found to agree with TEM results.

Electrochemical Nanoparticle Sizing Via Nano‐Impacts: How Large a Nanoparticle Can be Measured?

“…No well-definedA gBrr eduction peak is apparent;i nstead, sharp reductive features (spikes) are observed at potentials lower than À0.75 Vv s. as aturated mercury sulfate electrode (MSE). Thist ype of voltammetric response has been previously attributed to an ucleation overpotential required for particle reduction [14] and can be associated with reduction of AgBr to Ag:…”

“…Since the initial work on the direct electrolytic characterisation of silver NPs, the area has expanded to include a range of nanomaterials including gold, nickel, copper, iron oxide, mercury chloride, indigo, and poly(N‐vinylcarbazole) (PVK) . The method has also shown to be applicable via the use of various types of electrodes and electrode materials such as carbon and gold microdisks, carbon fibre microcylinders, liquid hemispheres, and random microelectrode assemblies (RAMs)…”

“…Since the initial work on the direct electrolytic characterisation of silver NPs, [7] the area has expanded to include ar ange of nanomaterials including gold, [8,9] nickel, [10,11] copper, [12] iron oxide, [13] mercury chloride, [14] indigo, [15] and poly(N-vinylcarbazole) (PVK). [16] The methodh as also shown to be applicable via the use of various typeso fe lectrodes ande lectrode materials such as carbon [7] and gold [17] microdisks, carbon fibre microcylinders, [18] liquid hemispheres, [14] and random microelectrode assemblies (RAMs). [19] Despite al arge variety of NP materials having now been characterised, [20] the limits of this technique with respect to the size of the particles till needs clarification.R ecent work has soughtt oc larify the lower limit of detection, having achieved successful sizing of 6.3 nm diameter silver NPs by minimising background electricalnoise.…”

Recent Advances in Voltammetry

“…This requirement has led some researchers to use mercury as the ‘inert’ electrode substrate . However, problematically in the presence of trace chloride, mercury is readily oxidised to form calomel nanoparticles . Once formed, these calomel nanoparticles are easily reduced at the mercury electrode and can lead to results which may be misinterpreted.…”

Single Nanotube Voltammetry: Current Fluctuations Are Due to Physical Motion of the Nanotube

“…14,15 The use of carbon as a supporting electrode material is often beneficial due to the commonly associated sluggish heterogeneous electron transfer kinetics. 16 Alternative metallic materials which often exhibit slow electron transfer kinetics, such as mercury, 17−19 are complicated by the ready formation of chloride salts 20 which can and do lead to erroneous results.…”