Research Projects

Organic photovoltaics (OPVs) represent a cutting-edge renewable energy technology, known for their low-cost fabrication and environmentally friendly materials. Over the past two decades, significant advances in materials science and device engineering have boosted OPVs to exceed 20% power conversion efficiencies (PCEs) in outdoor applications, rivalling traditional silicon photovoltaics. However, their outdoor deployment is hindered by UV degradation, temperature fluctuations, moisture sensitivity, and fabrication challenges, limiting large-scale implementation. In contrast, indoor environments offer a promising path for OPV utilization. Artificial light sources such as LEDs, CFLs, and halogens as well as filtered sunlight, serve as consistent and accessible power sources for low-consumption electronics. Organic semiconductors excel under these low-intensity conditions, outperforming conventional inorganic systems due to their adjustable optical properties, high absorption coefficients, and minimal leakage currents. Recent research shows that indoor organic photovoltaics (IOPVs) can achieve PCEs of 30–45% under artificial lighting and up to 17% under standard sunlight, establishing them as a strong candidate for indoor energy harvesting. They hold transformative potential for powering wireless sensors, smart meters, wearable healthcare devices, and other IoT systems that currently rely on batteries often difficult to replace or maintain. Indoor light intensity ranges from 200–1000 lux, significantly lower than outdoor sunlight (~100,000 lux). The emission spectra of indoor light sources are primarily in the visible spectrum (around 390–760 nm), which overlaps well with the absorption spectra of many organic semiconductors used in OPV applications, it is essential to produce broad band-gap organic semiconductors with high absorption coefficients, with an optical bandgap between 1.8 and 2.1 eV and a good spectral overlap with indoor light source to reach higher PCEs. This project will focus on three key objectives: (1) design and synthesize tailored donor–acceptor materials, (2) optimize device architectures for indoor performance, and (3) evaluate stability and efficiency under various illumination levels (e.g., LED, CFL). We hypothesize that with precise spectral alignment and interface optimization, IOPV devices can exceed 30% PCE under 1000 lux with high operational stability. The study will involve synthesizing new materials, characterizing their optoelectronic properties, fabricating devices via spin-coating and thermal evaporation, and assessing device performance through J–V characteristics and long-term stability tests. The rapid evolution of IOPV technology suggests strong commercial and environmental potential. Continued progress in materials and architecture design will accelerate scalable, sustainable indoor PV solutions, driving forward a new generation of self-powered electronics.