Engineered carrier transport in nanostructured semiconductors using functional disorder.

Descripción del proyecto

El desorden controlado mejora el transporte de los portadores de carga en semiconductores nanoestructurados

Los llamados materiales desordenados no tienen orden a larga distancia, pero pueden tener correlaciones locales u orden entre átomos o moléculas. Los líquidos y los vidrios son quizá los más conocidos. En los materiales semiconductores, sobre todo en los nanoestructurados, se cree que el desorden impide el transporte de los portadores de carga, por lo que la mayoría de las investigaciones se han orientado a minimizarlo. Sin embargo, los resultados de estudios recientes indican que el desorden puede, por el contrario, potenciar el transporte de los portadores. Para aprovechar esta posibilidad, los científicos deben comprender mejor la relación entre el desorden y el transporte. El equipo del proyecto EnVision, financiado por el CEI, desarrollará la microscopía hiperespectral de transitorios, una técnica pionera de superresolución capaz de visualizar simultáneamente las dimensiones temporal, espacial y energética asociadas al transporte de los portadores.

Objetivo

Disorder is generally considered to have a purely negative impact on carrier transport and most efforts aim to minimize it. However, recent studies suggest that disorder may enhance carrier transport via carrier funneling along energetic gradients or promote carrier interconversion at defect sites. Critically though, before disorder can be exploited for improved optoelectronic performance of nanomaterials, a better understanding of the relationship between disorder and transport is needed.

EnVision aims to build a bridge between fundamental observations of the benefits of disorder and materials engineering. To enable this, I have designed a two-fold strategy focussed on 1) defining the detailed design rules for the rational design of disorder driven carrier transport and interconversion, and 2) develop strategies to engineer the local energy landscapes of nanostructured semiconductors that boost carrier transport and interconversion.

To enable the definition of the detailed design rules, I will take the crucial step of developing Hyperspectral Transient Microscopy – the first super-resolution technique capable of simultaneously visualizing the transport of carriers in space, time, and energy. Using metal-halide perovskites as a versatile testbed, EnVision will make critical advances beyond the current state-of-the-art in promoting carrier transport along compositional gradients, boost carrier interconversion at local dopants site, and the creation of on-demand energy landscapes using nanoindentation.

Through its unique approach, EnVision will introduce the concept of functional disorder, paving the way for new formalisms nanomaterial engineering and guiding the realization of fully optimized energy landscapes for optoelectronic and photonic technologies.