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Nov 02, 2023 268 likes •335 views

3/11/2015 GOAL: Korgel Group Make photovoltaic NHB 6.406 (PV) electricity a korgel@che.utexas.edu major source of http://www.che.utexas.edu/korgel group/ energy Nanomaterials Chemistry and Engineering New concepts enabled by

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3/11/2015 1 Korgel Group NHB 6.406

korgel@che.utexas.edu http://www.che.utexas.edu/korgel‐group/

Nanomaterials Chemistry and Engineering

Photovoltaics Lithium ion batteries Silicon nanocrystals and nanocrystal/liposome complexes Nanocrystal superlattices

GOAL: Make photovoltaic (PV) electricity a major source of energy “Low-cost solar cells that can be printed like newspaper”

New concepts enabled by nanotechnology:

Chemical synthesis of CIGS nanocrystals

Dariya Reid (undergraduate chemical engineer)

leylamine, 240oC

CuCl + InCl3 + 2Se CuInSe2 nanocrystals

CISe Organic capping ligands

~15 nm

Nanocrystal ink n-type semiconductor Metal Metal Glass or plastic support Concept: process the semiconductor layer by room temperature ink deposition

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3/11/2015 2

Efficiency of 2%

n plastic

The challenge is to demonstrate commercially viable efficiencies of >10% (currently, the devices function at 3%)

Bulk silicon Silicon fabric

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3/11/2015 3 Integrated Energy Storage and Harvesting

Silicon Nanorods

Thiol‐capped Si nanocrystals ligand‐exchanged with dodecene exposed ethanol (with air/water)

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3/11/2015 4 Nanocrystal/Liposome complexes for combined medical diagnostics & therapy

Approach: Pre-synthesize nanocrystals and then add to vesicles

Question: will hydrophobic nanocrystals embed in the vesicle membrane without disrupting its formation? If so, is there a size limitation? (Membrane thickness is 3.7 nm)

Image from: http://www.uzh.ch/onkwww/images/lipos4.gif

Hydrophobic Nanocrystals in Vesicles (Liposomes)

3.7 nm

Liposomes

No nanocrystals w/ Au nanocrystals

Many fully‐loaded vesicles are

found across the grid

Many vesicles without

nanocrystals observed as well

Loading NCs Into Vesicles: Sonication & Extrusion

1500 lipid molecules per Au NC

~1300 NC/vesicle calculated for 1.6 nm Au & 50 nm vesicle

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3/11/2015 5 Cryo-TEM Images of Au nanocrystal-loaded PC vesicles made by sonication/extrusion

Korgel group Current focus on photovoltaic devices (solar cells), lithium ion batteries and medical applications of silicon Research involves materials discovery, advanced analytical characterization, and device/application prototyping Highly collaborative group—interdisciplinary research without boundaries