UCLA

Dickerson Biochemistry Chemistry Seminar 268: Prof. Jose Rodriguez and Prof. Kalli Kappel
2025-11-14 15:30 - 17:00 (America/Los_Angeles)

Houk-Jung Organic Colloquium 247 - Prof. Darci Trader
2025-11-13 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Physical Chemistry Seminar 228: Carl Percival
2025-11-10 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: Hang Chi Ho
2025-11-10 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Chemistry Seminar 268: Prof. Michael Lawson and Prof. Antonio Tinoco Valencia
2025-11-07 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Houk-Jung Organic Colloquium 247 - Prof. Colleen Scott
2025-11-06 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 218 Student Exit Talk: Diego Garcia Vidales
2025-11-06 12:00 - 13:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Conjugated polymers are electronic materials that combine semiconductor-like behavior with mechanical flexibility, solution processability, and chemical tunability. However, their intrinsically low carrier density and heterogeneous microstructure pose challenges for efficient charge transport. To mitigate the low carrier density, we incorporate carriers via chemical doping into semiconducting polymer thin films. This talk investigates how chemical doping and polymer morphology jointly dictate charge transport across molecular, mesoscale, and macroscopic length scales, with implications for electronic and thermoelectric applications. We characterize the doped films using techniques such as four-point probe conductivity, Seebeck coefficient measurements, Hall effect measurements, X-ray scattering, and spectroscopy. We first study how the hygroscopicity of the counterions in doped polymer thin films can significantly influence electronic transport by enabling water uptake. We show that absorbed moisture introduces trap states and suppresses carrier mobility, underscoring the need to consider environmental stability and dopant chemistry when chemically doping polymer devices. Second, we dope the same polymer with four molecular dopants and find that the choice of dopant affects not only carrier generation but also structural ordering, crystallite connectivity, and Coulomb trapping, leading to distinct charge-transport pathways and thermoelectric performance. Importantly, we show that electrical conduction can be enhanced without sacrificing Seebeck coefficient either by mitigating Coulomb interactions or by activating charge transport through previously amorphous regions. Finally, we isolate the role of the polymer microstructure by tuning the polymer crystallinity by controlling regioregularity. We find that higher intrinsic crystallinity promotes greater polaron delocalization and faster local transport, and that dopant- induced crystallization in amorphous regions can enhance mesoscale connectivity. The combination of high local order and doping-enabled long-range connectivity is essential for maximizing mobility and thermoelectric performance. Overall, this work establishes structure–doping–transport relationships in doped conjugated polymers and highlights design principles for next-generation polymer conductors: choose dopants that both minimize trapping and enable structural reinforcement, and engineer polymer microstructure to balance local order and mesoscale connectivity.

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Jun Ohata
2025-11-05 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Physical Chemistry Seminar 228: Prof. Sergio Carbajo
2025-11-03 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: James Collings
2025-11-03 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Chemistry Seminar 268: Prof. Carla Koehler and Prof. William Gelbart
2025-10-31 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

UCLA AMGEN Leadership - Prof. Huw Davies | Dr. Joshua Gladfelder
2025-10-30 15:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Anna Wuttig
2025-10-29 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Physical Chemistry Seminar 228: Jonathan Hood
2025-10-27 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: Clifford Leung
2025-10-27 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Chemistry Seminar 268: Prof. Alexander Spokoyny and Prof. Stefan Petrovic
2025-10-24 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Houk-Jung Organic Colloquium 247 - Prof. Leonori Daniele
2025-10-23 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Matt Nava
2025-10-22 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Distinguished Lecture Series - Elizabeth Villa
2025-10-20 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Chem 248 Organic Chemistry Student Seminar: Samuel Hugie
2025-10-20 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Chemistry Seminar 268: Prof. Juli Feigon and Prof. Steven Clarke
2025-10-17 03:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Houk-Jung Organic Colloquium 247 - Prof. Bil Clemons (Sponsored by OCDS)
2025-10-16 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Kyoko Nazaki
2025-10-15 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Physical Chemistry Seminar 228: Stacy Copp
2025-10-13 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: Jett Vuong
2025-10-13 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Chemistry Seminar 268: Prof. Guillaume Chanfreau and Prof. Margot Quinlan
2025-10-10 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Houk-Jung Organic Colloquium 247 - Prof. Matthew Bogyo
2025-10-09 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Yayuan Liu
2025-10-08 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Inorganic Chemistry Student Exit Talk: Zhiyin (Tara) Yang
2025-10-07 12:00 - 13:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Physical Chemistry Seminar 228: Prof. Christopher Gutiérrez
2025-10-06 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
