The heterogeneous electron transfer reaction is always moderated by the electric double layer (EDL) structure and its dynamics. The extent of dynamic coupling between diffusion controlled electron transfer and EDL is studied in this work. The high frequency (w > wH) EIS response unravels the formation of EDL with a characteristic frequency wH and is the prerequisite for electron transfer step. This response is dominated by the solution resistance and ions reorganization. The dynamics of EDL is influenced by various factors like externally applied potential, concentration of electrolytes, viscosity of the medium and temperature. The intermediate frequency (w < wH) regime is controlled by the potential dependent coupling of the charge transfer kinetics, diffusion and EDL processes. This superposition of EDL and diffusion controlled response is also influenced by the morphological complexities of fractal electrode surface, viz. DH, l and lꞇ and on medium characteristics, viz. viscosity and temperature. The modular multi-phenomena approach for the prediction of the impedance and is also used to interpret the experimental EIS. The enhanced viscosity of the electrolyte results in a lowering of diffusion coefficient which leads to (i) an increase in double layer contribution and (ii) shifts in the time scale of EDL formation, i.e. wH. The temperature variation range which is studied is 10°C to 25°C in both the aqueous and 90% glycerol medium for 30 mV and 60 mV potential away from the peak. The decrease in temperature also lowers the EDL formation frequency wH. The low frequency behaviour is dominated by the sluggish water splitting kinetics which truncates intermediate regime. Finally, the experimental impedance response for rough Pt electrode in aqueous and 90% glycerol medium for 10°C to 25°C temperature range is interpreted through the modular theoretical approach.

The heterogeneous electron transfer reaction is always moderated by the electric double layer (EDL) structure and its dynamics. The extent of dynamic coupling between diffusion controlled electron transfer and EDL is studied in this work. The high frequency (**w** > **w**H) EIS response unravels the formation of EDL with a characteristic frequency **w**H and is the prerequisite for electron transfer step. This response is dominated by the solution resistance and ions reorganization. The dynamics of EDL is influenced by various factors like externally applied potential, concentration of electrolytes, viscosity of the medium and temperature. The intermediate frequency (**w** < **w**H) regime is controlled by the potential dependent coupling of the charge transfer kinetics, diffusion and EDL processes. This superposition of EDL and diffusion controlled response is also influenced by the morphological complexities of fractal electrode surface, viz. DH, l and lꞇ and on medium characteristics, viz. viscosity and temperature. The modular multi-phenomena approach for the prediction of the impedance and is also used to interpret the experimental EIS. The enhanced viscosity of the electrolyte results in a lowering of diffusion coefficient which leads to (i) an increase in double layer contribution and (ii) shifts in the time scale of EDL formation, i.e. **w**H. The temperature variation range which is studied is 10°C to 25°C in both the aqueous and 90% glycerol medium for 30 mV and 60 mV potential away from the peak. The decrease in temperature also lowers the EDL formation frequency **w**H. The low frequency behaviour is dominated by the sluggish water splitting kinetics which truncates intermediate regime. Finally, the experimental impedance response for rough Pt electrode in aqueous and 90% glycerol medium for 10°C to 25°C temperature range is interpreted through the modular theoretical approach.

Dynamic Influence of Electric Double layer in Electron Transfer Reaction

In order to view the entire gallery of posters, videos, and other materials, please click "Submissions" below. 

To find the Q&A for each poster category, please click "Sessions" below. 

To ask a question, simply click on the session of interest. You will see a list of video presentations to the right. Below each video area, you'll see a section entitled 'Q&A for this presentation'. Here you can post questions to the presenters. They will be notified, and you'll also be notified when they reply to your question. You can expect that notification by email, and you'll find the author's response here.

27th CRSI National Symposium in Chemistry

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.