Dye Sensitized Solar Cells by an

aerosol jet 3D printing mechanism

Dr. Om Prakash SinghAsst. Professor, IIT Mandi

www.omprakashsingh.com

Thin film solar cell

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• The volume of the spheres is proportional to the amount of energy they represent.• Global solar power of 23,000 TW refers to the earth's total land mass with atmospheric

losses taken into account, and corresponds to 200 million TWh per year.• Worldwide energy consumption of 16 TW during year 2009 translates into 140,000

TWh.

Renewables: TWConventional: TW-yr

More energy fromsunlight strikesEarth in 1 hourthan all of theenergy consumedby humans in anentire year.

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Cost of Wind and Solar power reducing every year

• Hence, any new initiative/technology for energy

harvesting (however small) may prove beneficial in

long term.

http://rameznaam.com/2014/09/29/the-renewable-energy-revolution/

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A brief Bio of Silicon Solar cell: Humble beginning

• French physicist Alexandre-Edmond Becquerel inadvertently observed the

photovoltaic effect around 1839 while manipulating an electrode inside a

conductive fluid exposed to light.

• American inventor Charles Fritts: fabricated the first photovoltaic (solar)

cell around 1883.

• His approach involved coating selenium with a thin layer of gold, creating a

cell that was less than 1% efficient at best, but it worked.

• Of course the high cost of the materials selenium and gold put a bit of

tarnish on his accomplishment.

• Russian physicist Aleksandr Stoletov (1888) assembling a photoelectric cell

based on a photoelectric effect discovered by Heinrich Hertz in 1887.

• In 1905, Albert Einstein explained the photoelectric effect (got novel prize)

• American engineer Russell Shoemaker Ohl patented the junction

semiconductor solar cell in 1946 while performing research that would lead

to the invention of the transistor.

• Bell Laboratories gets credit for developing the first efficient photovoltaic

cell in 1954.

• Solar-cell progress, however, was quite slow for about 20 years until Exxon’s

Eliot Berman made some price and efficiency breakthroughs.

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• DSSC uses a thin film of titanium dioxide(TiO2) which has been ground to a finepowder (nanocrystalline) to increase itsreactive surface area.

• The TiO2 is sandwiched between two glassslides that are coated with conductive andtransparent indium tin oxide (ITO).

• The TiO2 is impregnated with some kind ofcolored dye, in this case anthocyanin fromraspberry juice, which is the chemical whichfirst traps the solar energy and passes thecharge to the TiO2.

• Finally the space between the slides is filledwith an liquid electrolyte solution ofpotassium iodide which serves to transportcharge (by way of a redox reaction) fromthe bottom electrode to the dye tocomplete the circuit.

Dye sensitized solar cell: How it works

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Construction of TiO2 solar cell

• Transparent conducting films(TCFs) are optically transparentand electrically conductive inthin layers.

• Indium tin oxide (ITO) is themost widely used

• Alternatives including othertransparent conductive oxides(TCOs), generally in the form ofindium tin oxide (ITO), fluorinedoped tin oxide (FTO), anddoped zinc oxide.

• Transparent conducting filmsact as a window for light topass through to the activematerial beneath (wherecarrier generation occurs)

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Dye Sensitize or Thin Film Solar cell

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Life is all about motivation

“There’s is none in all three worlds who can stop you….

Mediate on your strength… O Hanuman most mighty”

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• Student, 4th Year, Mechanical when project started

• Published journal paper and filed patents.

• Now they are working in power sector companies.

Students worked on the project

TiO2 Solar CellAPPARATUS:

• Conducting glass

• TiO2 solution

• Iodide or Tri-iodide (Electrolyte)

• Cis-(NCS)2bis(4,4’ dicarboxy-2,2’bipyridine)-ruthenium-II dye (which is adsorbed on TiO2 ) (DYE)

• Negative electrode : graphite

• Cleansing solutions and surfactants: ethanol , dil -acetic acid

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Design of Dye Sensitized Solar 3D PrinterBack view

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Stepper MotorsV1 & V2

Support bars

Heating plate

Support bars todamp vibrations

Nozzle

Stepper Motor H1

Design of Dye Sensitized Solar 3D PrinterFront view

• Slider Crank Mechanismfor extruding TiO2 pastefrom nozzle exit

• Considered Gubler’scriteria in Designing slidercrank

• Also tried with Rack andPinion method (But did not

work out )

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Required design specifications: stepper motors

m

fNPr

• RPM of servo motors = T/I

• Torque max required along the y-axis = 6.2 kg mm2/s2

approx.

• TL>0 For self locking or the nozzle setup will lower itself. TL = 5.8 kg mm2/s2

ʎ

Assuming approx. mass= 400gm

• Dm=6mm P=1mm (ANSI) For 1 full rotation of screw 360 deg rotation of motor.• Hence for a 5cm

strip printing 50 full rotation of motor.

V1 & V2 H1

• No of steps in 1 full rotation of motor shaft = N = 4 x no. of teeth

• Deg per step = 360/N

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Screw

Tio2 mix pump

Inlet Tio2

Outlet Tio2

MotorTiO2 Pump design

• PR/Area = Pressure at outlet > Atm Pressure

Why Tio2 pump?1. To provide a uniformly mixed Tio2

solution.2. To provide the sufficient pressure for the

extrusion of the solution.3. Heat generated by conversion of

mechanical energy into thermal energyimproves the conductivity of themixture.

For Pump..

𝑃𝑅 =𝐹(𝑠𝑖𝑛𝜆 + 𝑓𝑐𝑜𝑠𝜆)

𝑐𝑜𝑠𝜆 − 𝑓𝑠𝑖𝑛𝜆

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Design Parameters

• The thickness of TiO2 layer should beIdeally less than 200 m (0.2 mm)

• Conductivity properties of TiO2: HeatedNozzle in 3D Printer

• The conductivity of TiO2 increases by afactor of 107 over the temperature rangeof 30-420 Centigrade

• Nozzle and Extruder design

• Spectral Irradiance and operatingwavelength

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Nozzle Diameter Design

nozzle

Droplet sphere

Droplet on base

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Extruder Design

TiO2 inlet

Power screw

Nozzle

Heating Equipment

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1. Micro controller : Arduino MEGA 25602. Motor Driver Mount : Ramps 1.43.Power source : 12V,30A power source3. Motors : Nema 17 stepper motors4. Motor Drivers : Polulo A49885.Heated Bed : Prusa PCB Heated Bed Mk 2B

Electronic components details

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Circuit diagram

Final Product : The Solar Cell

3D printed layer Dye Immersion Carbon Negative Electrode

Electricity generation

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Application examples of dye sensitized solar cells and modules: (a) 200 m2 of STI DSSCpanels installed in Newcastle (Australia)– the first commercial DSSC module(http://www.sta.com.au/index.htm), (b) indoor ornament of dye sensitized solar cells leaves(AISIN SEIKI CO.,LTD), (c) flexible DSSC-based solar module developed by Dyesol(http://www.dyesol.com), and (d) jacket commercialized by G24i(http://www.g24i.com).

Application and Commercialization of DSSC

Flexible thin-film solar panels install easily on commercial rooftops

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A prototype of a flexible dye sensitized solar cell using stainless steel substrate (From Kang et al., 2006).

Flexible dye sensitized solar cell

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• Availability of nonvolatile electrolyte is another issue toward

commercialization of single or multi-junction modules.

• Polymer (solid) electrolyte, hole conductor, and solidified ionic liquids are

solvent free choices with high electronic conductivity and chemical stability

(Wang et al., 2005.)

• The key to high power heterojunction DSSC is to increase the effective

diffusion length of electron within the nanostructured electrode by increasing

the mobility of hole conductor or the extinction coefficient of the sensitizer to

ensure more efficient light harvesting action.

• Since heat and UV light degrade cells performance, development of heat sink

and optimized low cost UV coating is a must for outdoor applications.

• The successes in development of flexible substrate, solid electrolyte, and

spectrally broad absorption range inexpensive nontoxic dyes will potentially

open the possibility of role-to-role mass production of dye sensitized solar cells

and modules

• The successes in development of flexible substrate, solid electrolyte, and

spectrally broad absorption range inexpensive nontoxic dyes will potentially

open the possibility of role-to-role mass production of dye sensitized solar cells

and modules

The future: Solid state electrolyte

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Schematic of role-to-role manufacturing of flexible dye sensitized solar cells.

Mass production: Can it be done by 3D printer?

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ComparisonSemi-conductive

Solar cellsDSSC

Power generation/ Manufacturing cost

High Low

Environmental Friendly Normal Great

Flexibility Low HighEfficiency High (20%) Moderate (13%)

Life Long ModerateBuilding integrated

Photo-voltaicLow usage High usage

Indoor lighting applications

No Yes

Silicon solar cell vs. Dye Sensitized Solar Cell

Transparency Opaque Transparent

Color Limited VariousGlobal warming Bad (high Tc) Good (low Tc )26

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The future: To extend the operation of TiO2 solar cell in visible range & infrared region by suitable dopants.

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Science is beautiful but

Engineering is fun

• Looking for collaborations to develop future

technology

• Thin film solar cells is next billion dollar market.

• 100s of patents expected.

• Let us create IPR for nation building.

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Concluding remarks• A 3D Printer prototype for making thin

film Dye Sensitized Solar Cell developed

• Concept shows 3D Printers can play a

significant role

• Almost nobody is looking at the engineering

side e.g. fabricating thin solar cells using

3D Printer

• Need to automate other processes such e.g.

Dye addition and electrode combination.

• Collaborations with Industry and Academia

seems only way to develop new technologies

for printing solar cells

• Lets us join hand today for better

tomorrow.

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Thank you your attention