Enabling Scalable Production and Processing of Nanoparticles

for Emerging Energy Applications (NSF-CMMI-1344562)

Curtis Williamson, Douglas R. Nevers, Tobias Hanrath, Richard D. Robinson

Robert F. Smith School of Chemical and Biomolecular Engineering and Department of Material Science and Engineering, Cornell University, Ithaca, NY, 14853

We thank: John Grazul and Lena Kourkoutis for

assistance with the TEM. Stan Stoupin for

assistance with X-ray scattering.

NSF CMMI-1344562, NSF DMR-1719875,

NSF DMR-1332208

Introduction

Nanoparticle Synthesis Scale-Up

Applications

1) Pushing precursor concentration to the solubility limit decouples mixing and NP growth and

thereby enables highly reproducible nano fabrication of high-fidelity NPs.

2) NP reaction was successfully scaled 100× in volume to 2.5 L and demonstrated scale-up to

215 g with an unprecedented yield of 86 g/L and a precursor conversion exceeding 90%.

3) Increased viscosity provides a more controlled, uniform synthesis environment that self-

restores and size-focuses.

4) High-concentration, heat-up methodology has significant potential to resolve outstanding

challenges to fabricate NP building blocks at scales capable of meeting their emerging

demand.

5) Direct synthesis of high-purity magic-sized clusters, enabling understanding of their

stabilization mechanism and surface-sensitive isomerization.

Summary

4J. Mater. Chem. A, 2016, 4, 2848

6J. Mater. Chem. C, 2015, 3, 1044

5ACS Appl. Mater. Interfaces, 2015, 7, 25053

1Chem. Mater., 2015, 27,7873 2J. Mater. Chem. A, 2015, 3, 4274 3Chem. Commun., 2017, 53, 2866

LED emitter1

Water-splitting4

Battery5

Supercapacitor6

Sensor3

2.5x EPD

Drop-cast

Catalysts2

CuInS2

Co3-xMnxO4

Cu2-xS

CoOxSy

CdS

Co3O4

50 nm

Why Nanoparticles?

Ref. 2.

Size tunable properties

Ref. 3.

Nanoparticle

Building Block

Nano Components Integrated System Transistor

Science, 2016, 352, 205

Source/Drain Channel

Gate Insulator

Enhanced Technologies

Our Focus Synthesis • Scale-up • Integration

Volume

Conventional

synthesis

Prohibitively

large reactors

Ultra-high concentration

produces robust

reactions

< 100 mM

1 kg Need a

142 L flask!!

How can nanoparticle synthesis be scaled to kilogram levels while

maintaining precisely controlled size, shape, and composition?

Scale-up cannot simply be achieved by just using a bigger reactor Decoupling the disassociation and reaction rates is a key challenge for scalable NP synthesis. The

“state of the art” conventional hot injection intertwines reaction steps, complicating scale-up. We

took a fresh ‘heat-up’ method approach driven by the hypothesis that significantly increasing the

precursor concentration provides unexplored opportunities to control NP nucleation and growth.

Specifically, we sought to

1) Control growth rates for size-focusing,

2) Maintain temperature uniformity throughout

synthesis, and

3) Demonstrate rigorous control of system

stability to perturbations.

Highly concentrated solutions in

the ‘heat-up’ method size focuses

and become monodisperse;

whereas the conventional

concentration synthesis Ostwald-

ripens..

2.5 L reaction of Cu2-xS nanoparticles

Size and RSD: 8.0 nm ± 9.3%

Total mass = 215 g (after purification and

drying)

Ligand Content ~20% wt (TGA)

Total conversion > 93%

High Concentration at Large Scale

Increasin

g C

oncen

tration

Scale bar: 20 nm

500 mM

1000 mM

100 mM

Effect of Concentration on Synthesis

RSD =Relative Size Distribution

High concentrations reduce particle

mobility and stabilize growth.

Magic-sized Clusters

Next Steps: Device Integration

F324 F313

Structural Isomerization

Clusters

Nanoparticles

Tim

e

J. Am. Chem. Soc. 2015, 137, 15843

Mesophases Formation

Atomically Precise

High-purity: >99.9%

FWHM: 8 nm

RSD: < 3%

Large Scale

0Q

1Q

2Q

1Q

√3Q

√7Q SAXS

1Q

√3Q

√7Q

2Q

50 nm

d

Mesophase formation stabilize

clusters against growth.

J. Mater. Chem. A, 2015, 3, 4274

Nano Letters, 2012, 12, 5122

Enhanced Film Stability

Nano Letters, 2012, 12, 5122

Better Batteries

Efficient Catalysis

Improved Conductivity

ACS Appl. Mater. Interfaces, 2014, 18911

ACS Appl. Mater. Interfaces, 2015, 25053

Advantages

Uniform films

Improved connectivity

Solution processing

Roll-to-roll integration

Electrophoretic Deposition (EPD): Drive particle deposition using potential difference

EPD Enabled