Quantum Dot Research in the Niezgoda Lab
Quantum dots are a fascinating group of materials that were discovered and characterized during the burst of nanoscience that has occurred over the last couple decades. Quantum dots are semiconductor nanocrystals whose size is so small, we can think them as zero-dimensional. In reality, they range in diameter from less than 1 nanometer (1 billionth of a meter) to tens of nanometers, containing hundreds to thousands of atoms. Interestingly, at this tiny size scale, these crystals exhibit properties that they wouldn't at larger sizes. Nanoscientists can tune the color of light these quantum dots emit (LEDs in TVs), they can adjust the energy of light they absorb (solar cells, photocatalysis), and they can use them as fluorescent markers for linking and tracking or delivering other chemicals (cell protein tracking, drug delivery).
Transmission electron microscopy image of a single quantum dot
Each line you see is a single row of atoms!
The Niezgoda lab's current research at SJU focuses on the chemical tailoring of surface bound molecules, or "ligands", on quantum dots. Specifically, the Niezgoda lab is interested in using known and polished quantum dot synthetic methods as scaffolds upon which to introduce previously unused chemicals onto their surface. These new chemicals can open myriad new optoelectronic and physical properties for the crystals, such as site-guided specific linking to given protein binding sites and chemical cross-linking of different specific types of dots. Undergraduate researchers in the Niezgoda lab will gain experience in both traditional chemical synthetic methods, as well as cutting-edge techniques in nanoscience through work with a new glovebox system, Schlenk line, and transmission electron microscopy (TEM) studies.
(12) Litle, E. M.; Stenseth, S.; Niezgoda, J. S., Changes without Exchanges: On-Particle Chemical Cleavage of a New Native Binding Ligand on CdSSe Quantum Dots. Chemistry of Materials 2021, 33, 1149-1156.
(11) Alpert, M.R.; Niezgoda, J.S.; Chen, A.; Foley, B.; Cuthriell, S.; Yoon, L.; Choi, J.J. Colloidal Nanocrystals as a Platform for Rapid Screening of Charge Trap Passivating Molecules for Metal Halide Perovskite Thin Films. Chemistry of Materials 2018, 30, 4515-4526.
(10) Niezgoda, J. S.; Foley, B. J.; Chen, A. Z.; Choi, J. J. Improved Charge Collection in Highly Efficiency CsPbBrI2 Solar Cells with Light-Induced Dealloying. ACS Energy Letters 2017, 2, 1043-1049.
(9) Chen, A.Z.; Foley, B. J.; Ma, J. H.; Alpert, M. R.; Niezgoda, J. S.; Choi, J.J., Crystallographic Orientation Propagation in Metal Halide Perovskite Thin Films. Journal of Materials Chemistry A 2017, 5, 7796-7800.
(8) Foley, B. J.; Girard, J.; Sorenson, B.; Chen, A.Z.; Niezgoda, J. S.; Alpert, M. R.; Harper, A.; Smilgies, D.M.; Clancy, P.; Saisi W.A..; Choi, J.J., Controlling Nucleation, Growth, and Orientation of CH3NH3PbI3 Perovskite Thin Films with Rationally Selected Additives. Journal of Materials Chemistry A 2017, 5, 113-123.
(7) Niezgoda, J.S.; Rosenthal, S.J., Synthetic Strategies for Semiconductor Nanoparticles Expressing Localized Surface Plasmons. ChemPhysChem 2016, 17, 645-653.
(6) Niezgoda, J.S.*; Ng, A.*; Mcbride, J. R.; Poplawsky, J.D.; Pennycook, S. J.; Rosenthal, S. J. Visualization of Current and Mapping of Elements in Quantum Dot Solar Cells. Advanced Functional Materials 2015, 26, 895-902. (*equal contribution)
(5) Gizzie, E. A.*; Niezgoda, J.S.*; Jennings, G. K.; Rosenthal, S. J.; Cliffel, D. E. Photosystem I-Polyaniline/TiO2Solid-State Solar Cells: Simple Devices for Biohybrid Solar Energy Conversion. Energy & Environmental Science 2015, 8, 3572-3576. (*equal contribution)
(4) Prasai, D.; Klots, A., Niezgoda, J. S.; Newaz, AKM; Escobar, C.; Rosenthal, S. J.; Jennings, K.; Bolotin, K. I., Electrical Control of Near-Field Energy Transfer Between Quantum Dots and Two-Dimensional Semiconductors. Nano Letters 2015, 15, 4374-4380.
(3) Niezgoda, J. S.; Yap, E.; Keene, J. D.; McBride, J. R.; Rosenthal, S. J., Plasmonic CuxInyS2 Quantum Dots Make Better Photovoltaics Than Their non-Plasmonic Counterparts. Nano Letters 2014, 14, 3262-3269.
(2) Piotrowski, M.; Forman, M.; Blithe, C.; Dougher, A.; Millet, C.; Montemareno, M.; Niezoda, J. S.; Rao, U., Industrial and Agricultural Pollutants in the Susquehanna Watershed of Pennsylvania. Abstracts of Papers of American Chemical Society 2013, 245, 632.
(1) Niezgoda, J. S.; Harrison, M. A.; McBride, J. R.; Rosenthal, S. J., Novel Synthesis of Chalcopyrite CuxInyS2Quantum Dots with Tunable Localized Surface Plasmon Resonances. Chemistry of Materials 2012, 24, 3294-3297.