Invitation: PhD Proposal Defense of Srushti Kulkarni

Hello ME Community,
You are invited to join the PhD Proposal Defense of Srushti Kulkarni, on Friday, August 21, beginning at 11:30am.  The defense will be presented in person in the Engineering Building room 112. (NOT the Conference room)

Advisor: Dr. Deepa Madan

Title: "Engineering Electronic and Ionic Thermoelectric Materials and Devices for Sustainable Low-Grade Heat Energy Harvesting"

Abstract:  Flexible thermoelectric generators (f-TEGs) offer a promising approach for harvesting low-grade waste heat, yet their broader adoption is limited by the lack of scalable manufacturing strategies that simultaneously provide low thermal budgets, mechanical flexibility, and high thermoelectric performance. In this work, a scalable and energy-efficient strategy combining Xenon flash sintering with MXene (Ti₃C₂) incorporation is developed to fabricate dense, thick (>200 μm) p-type Bi₀.₅Sb₁.₅Te₃ (BST) films within milliseconds under ambient conditions. MXene enhances optical energy absorption and energy transport during flash sintering, while subsequent surface incorporation creates BST/MXene heterointerfaces that promote selective carrier filtering. The resulting films achieve a power factor of ~2100 μW m⁻¹ K⁻² and a ZT of 0.52, representing >120% improvement over pristine BST, while a five-leg flexible TEG delivers 171.7 μW (2.45 mW cm⁻²) at ΔT = 30 K with stable bending performance.

Extending thermoelectric energy harvesting to ionic systems, this research further proposes a continuous-output ionic thermoelectric (i-TE) platform based on an MXene/PVA-PAM hydrogel, utilizing thermo-diffusion of Cu2+ and SO42- ions and the redox reaction involving Cu/Cu2+ at the electrode interfaces to achieve high thermopower under low-grade temperature gradients. Collectively, these approaches aim to advance scalable, flexible electronic and ionic thermoelectric technologies for efficient harvesting of low-grade waste heat.