Qiwei Pan

Hybrid electrolytes with controlled network structures for lithium metal batteries.

Solid polymer electrolytes (SPEs) with tunable network structures are prepared by a facile one-pot reaction of polyhedral oligomeric silsesquioxane and poly(ethylene glycol). These SPEs, with high conductivity and high modulus, exhibit superior resistance to lithium dendrite growth even at high current densities. Measurements of lithium metal batteries with a LiFePO4 cathode show excellent cycling stability and rate capability.

Anisotropic ion transport in nanostructured solid polymer electrolytes

Solid polymer electrolytes (SPEs) with good room temperature ionic conductivity and a high shear modulus are needed for future energy storage devices. Extensive studies have been devoted to searching for SPE with these desired properties. In this review, we will discuss recent progresses on the correlation between nanoscale morphology and ion conductivity in SPEs. Specifically, we will focus on anisotropic ion transport in five different types of SPEs with distinct morphological controls: crystalline structure, block copolymers, mechanical stretching, hybrids/nanocomposites, and holographic polymerization.

Correlated Perovskites as a New Platform for Super-Broadband-Tunable Photonics

We report strong and non-volatile optical modulation utilizing electron-doping induced phase change of a perovskite, SmNiO<inf>3</inf>. Broadband modulation (λ=400nm–17μm) is demonstrated using thin-film SmNiO<inf>3</inf>, and narrowband modulation is realized with metasurfaces integrated with SmNiO<inf>3</inf>.

Active metasurface devices based on correlated perovskites

There has been persistent exploration of new active materials and novel device architectures to dynamically control light with larger modulation depth and increased spectral range, at faster speed, and using less power. In this presentation, I will present experimental results showing that samarium nickelate (SmNiO3), a prototypical phase-change perovskite nickelate, exhibits reversible large refractive index changes over an ultra-broad spectral range, from the visible to the long-wavelength mid-infrared (λ = 400 nm-17 μm). The super broadband performance is due to strong electron correlation effects that allow extraordinarily large bandgap tuning of the order of 3 eV, and this new mechanism can be exploited to create active photonic devices.

Correlated perovskites as a new platform for super broadband tunable photonics

We report strong and non-volatile optical modulation utilizing electron-doping induced phase change of a perovskite, SmNiO 3 . Broadband modulation (λ=400nm–17μm) is demonstrated using thin-film SmNiO 3 , and narrowband modulation is realized with metasurfaces integrated with SmNiO 3 .