Topic 1: Understanding Photogenerated Charge Carrier Dynamics in Molecular Semiconductors

We study the fundamental mechanisms of photoinduced charge generation and recombination in molecular semiconductor systems for solar energy conversion. Our research aims to reveal how excitons evolve into free charge carriers and how charge transfer states, energetic driving forces, and interfacial energetics influence charge separation efficiency. Using ultrafast and operando spectroscopic techniques over femtosecond-to-second timescales, we investigate non-equilibrium carrier dynamics, long-lived charge formation, and recombination pathways in organic photovoltaic, photocatalytic, and photoelectrochemical devices. Through these studies, we seek to establish photophysical design principles for highly efficient and stable light-energy conversion systems.

Topic 2: Correlating Thin-Film Morphology with Charge Carrier Dynamics

We explore the relationship between nanoscale thin-film morphology and charge carrier behavior in molecular semiconductor devices. Our research focuses on how molecular ordering, donor/acceptor phase separation, crystallinity, aggregation, and π–π interactions govern exciton diffusion, charge transport, and recombination losses. By integrating advanced structural characterization with transient spectroscopic analyses, we identify how morphological features influence carrier lifetimes and overall device performance. These insights enable the rational design of optimized semiconductor morphologies and interfaces for efficient and durable organic optoelectronic and solar fuel conversion technologies.

Topic 3: Interfacial Engineering in Photovoltaic and Optoelectronic Devices

We investigate interfacial charge transfer and recombination processes in photovoltaic and optoelectronic devices to improve charge extraction efficiency and operational stability. Our research focuses on energy level alignment, interfacial dipoles, trap suppression, and carrier transport engineering at semiconductor/electrode interfaces. We develop and optimize indoor organic photovoltaics, tandem solar cells, semitransparent optoelectronic devices, and organic/inorganic hybrid systems for next-generation energy conversion applications. In addition, we study photocarrier dynamics and interfacial reactions in perovskite, quantum dot, and hybrid semiconductor systems to establish efficient and stable device architectures.

Topic 4: Stability and Degradation Mechanisms in Energy Devices

We investigate the stability and degradation mechanisms of molecular semiconductor-based energy devices under operational conditions. Our research focuses on understanding how light, oxygen, moisture, heat, and interfacial reactions influence photophysical processes, morphology evolution, and device performance degradation in photovoltaic, photocatalytic, and photoelectrochemical systems. By correlating charge carrier dynamics, molecular packing, and interfacial stability with long-term operational behavior, we identify the key factors governing device lifetime. Through materials design and interface engineering, we aim to develop highly stable and durable light-energy conversion systems for practical applications.