The　triarylimidazoles　(TAIs)　constitute　a　promising　class　of　organic　electron　transfer　redox　mediators　that　have　been　used　to　achieve　indirect　electrochemical　C-H　bonds　activation　and　functionalization.　Herein　we　report　the　diffusion　and　electron　transfer　rates　for　the　oxidation　of　4-methoxybenzyl　alcohol　using　TAI　and　compare　its　electrochemical　behavior　with　that　of　tris(4-bromophenyl)amine　(TBPA).　The　results　contribute　to　our　understanding　of　the　electron　transfer　process　of　electrocatalytic　oxidation　using　TAIs,　and　offer　useful　guidelines　for　their　further　development　and　use.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.