Hybrid Carbon-Bismuth Nanoparticle Electrodes

for Energy Storage Applications

Trevor Yates, Junior, University of CincinnatiAdam McNeeley, Pre-Junior, University of Cincinnati William Barrett, Sophomore, University of Cincinnati

GRA: Abhinandh SankarAC: Dr. Anastasios Angelopoulos

1

Why is renewable energy important?

1. 86.4% of the world’s energy supply is based around fossil fuels2. At least millions of years for dead organisms to decompose and transform3. Energy demand doubles every 14 years

“By the year 2020, world energy consumption is projected to increase an additional 207 quadrillion (2.07 x 1017) BTUs. If the global consumption of renewable energy sources remains constant, the world’s available fossil fuel reserves will be consumed within 104 years.”- US Department of Energy, 2010

2

PurposeCarbon-Bismuth Studies

Vanadium Studies

Vanadium RedoxFlow

Batteries

http://img.wallpaperstock.net:81/windmills-wallpapers_22092_1600x1200.jpg

http://www.messib.eu/assets/images/VRB_1_general_layout_VRFB.jpg

3

http://www.digsdigs.com/photos/fiedler-house-christmas-lights-1.jpg

4

Cost Analysis: 1 KW UnitVanadium 1.5 M VOSO4 and 10 M H2SO4 electrolyte costs

$1.60/kg

Storage Tanks 153 Liters of electrolyte required to generate 1 kW

Pumps 0.0866 L/min flow required with 0.5 m head pressure

Electrodes Volume based on required current and current density

Membrane Same SA as electrode and Nafion 117 costs $100/ft2

Total: $64 (153 L electrolyte) + $500 (4 x 50 L Tanks) + $110 (1 hp pump) + $40 (2 electrodes) + $2,634 (26.34 ft2 membrane) = $3,348

5

Introduction

Basic Electrochemistry Vanadium Redox Flow Batteries Cyclic Voltammetry Application Methods Research Parameters Results and Interpretations Future Studies

6

Electrochemistry

The study of the flow of electrons in chemical reactions Redox Reactions Anode and Cathode Reaction Potentials

7

http://www.messib.eu/assets/images/VRB_1_general_layout_VRFB.jpg

8

Cyclic Voltammetry

Voltage Sweep Between two set values

Current Peaks Scan Rates

Determined by user

9

Layer by Layer

Standard DirectedBismuth

Tin (Sn)

Polymer

Carbon

Polymer

Bismuth

Tin (Sn)

Carbon

Polymer

10

What we Have Learned...

Polymer important for LbL NaOH wash helpful Particles deteriorate

Glovebox Carbon Stabilizes Bismuth sLbL is better than dLbL 4Bi + 3O2 2Bi2O3

11

Carbon

No Carbon

12

sLbL

dLbL

13

Vanadium Studies

Negative electrodeV3+/V2+

Reduction reaction happens near H+ reduction

Electrocatalyst

14

Bismuth as an Electrocatalyst

Makes it easier for electrochemical reaction to happenTerms of Cyclic Voltammetry

Shifts peak currents closer togetherIncreases peak current heights

15

-1 -0.8 -0.6 -0.4 -0.2

-8

-6

-4

-2

0

2

4

Potential (V vs Ag/AgCl)

Cur

rent

Den

sity

(m

A/c

m2 )

Bismuth Improves Performance of Negative Electrode

8-Layers/Carbon4-Layers/Carbon-Bismuth8-Layers/Carbon-Bismuth

4/Carbon-Bismuth

8/Carbon-Bismuth8/Carbon

16

Ipc and Ipa

Ipc

Cathodic peak current Bottom peak

Ipa

Anodic peak currentTop peak

17

How to Calculate Ipc and Ipa

Have to extrapolate line Finding a “baseline”

Why?Glassy Carbon produces current

This is considered zero

18

-1.4 -1.2 -1 -0.8 -0.6 -0.4 -0.2 0-0.01

-0.005

0

0.005

0.0140mV/s 8 Layer Carbon Control sLbL (Example)

Cur

rent

Den

sity

(m

A/c

m2)

Potential (V vs. Ag/AgCl)

19

Ipc and Ipa Results

Test Electrode

Ipc

(mA/cm2)

Ipa

(mA/cm2)

Epc (V) Epa (V) Abs(Ipa/Ipc)

ΔE (V)

Carbon Control

-0.00466 0.000759 -0.9618 -0.394 0.162855 0.5678

4 Layer Hybrid

-0.00364 0.001369 -0.9799 -0.4201 0.375996 0.5598

8 Layer Hybrid

-0.00418 0.001861 -0.8617 -0.4759 0.445386 0.3858

20

Interpretations

Carbon has little effect on reaction Bismuth improves reversibility and peak currentIncreasing amount also improves reversibility and peak current

21

Future Studies

Why Carbon stabilizes Bismuth peaksScanning electron microscope

Characterize what’s occurringScale up productionQuantify improvement on VRFB performance

22

Timeline23

Thank You NSF!

Grant ID No. 0756921EEC: 1004623

24

References1. http://www.energy.gov/science-innovation/energy-sources

2. http://www.ecology.com/2011/09/06/fossil-fuels-renewable-energy-resources/

3. http://www.messib.eu/assets/images/VRB_1_general_layout_VRFB.jpg

4. http://www.digsdigs.com/photos/fiedler-house-christmas-lights-1.jpg

5. http://img.wallpaperstock.net:81/windmills-wallpapers_22092_1600x1200.jpg

25

References Continued

• 6. Zhenguo Yang, Jianlu Zhang, et al. “Electrochemical Energy Storage for Green Grid” Chemical    Reviews, 2010 Pacific Northwest National Laboratory, Richland, Washington 99352, United States.

• 7. Dennis H. Evans, Kathleen M. O’Connell, et al. “Cyclic Voltammetry” Journal of Chemical Education, 1983 University of Wisconsin-Madison, Madison, WI 53706.

• 8. David J. Suarez, Zoraida Gonzalez, et al. “Graphite Felt Modified with Bismuth Nanoparticles as Negative Electrode in a Vanadium Redox Flow Battery” CHEMSUSCHEM, 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

• 9. Gareth Kear, Akeel A. Shah, and Frank C. Walsh. “Development of the all-vanadium redox flow battery for energy storage: a review of technological, financial and policy aspects” International Journal of Energy Research, 2012 Electrochemical Engineering Laboratory, Energy Technology Research Group, School of Engineering Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, UK.

26

Questions?27