Nanomaterials have shown great promise to aid in the challenges facing us today, yet individual material systems often have significant drawbacks that prevent successful adaptation. We seek to unite material systems to build nanoscale ‘circuits’ where we control the flow of light, energy, and spin. By combining these material systems as circuit components, we can uncover unique strengths and physics that are unachievable by individual components alone, opening up a number of new applications.
Applications of Triplet Fusion Upconversion
Triplet fusion upconversion utilizes excitonic properties in molecules to turn two low energy photons into one higher energy photon. This process is useful in cases where long wavelength light is too low in energy to be absorbed, such as solar cells, where this process can harvest sub-bandgap photons. It can also be useful in situations where delivery of blue light can be challenging due to its limited penetration depth, such as biological applications, where near infrared excitation avoids the scattering behavior of visible light in tissue. We are working to develop more efficient upconverting materials to meet the needs of these diverse applications.
Perovskite Light Emitting Diodes
Lead halide perovskites have shown phenomenal potential for photovoltaics and light emitting diodes due to their excellent optical and electronic properties. Within the last few years, green and red perovskite LEDs have reached EQEs that are increasingly competitive with organic LEDs. Blue perovskite LEDs, however, have lagged far behind those high efficiencies, and the stability of these materials remains subpar.
To fix these issues, we are building efficient and stable perovskite LEDs across the visible spectrum. We are utilizing a variety of nanoscale perovskite materials and studying their structural, optical and electronic properties. We use a wide range of spectroscopies to understand the material properties and study the device physics in order to build the next generation of perovskite devices. Recent results from our lab have found that introducing dopants into these materials can play an important role – see the Publications page for more information!