Awarded CINEMA Projects

Name of CINEMA Fellow: Robson Raphael Guimarães
Name of CINEMA Research Mentor: Ju Li
Organization of CINEMA Research Mentor: Massachusetts Institute of Technology
CINEMA Energy Science Area of Research: Materials and devices for electrical energy storage

Rechargeable batteries have been developed to power a wide range of electronic devices such as electric vehicles, smartphones, and computers. However, the high demand for energy and the size limitations of those devices require the development of more efficient, robust and compact batteries. Currently, the renewable energy plays an important role in generating of environmentally friendly energy, but it exhibits high variability of energy harvesting along a day. Therefore, the improvement of battery technologies is essential for better harvesting and using those resources, minimizing the human impact on the planet.

Nickel-metal hydride batteries (NiMH) feature high energy density and high charge/discharge rate combining with the use of less harmful materials to the environment. Typically the α-Ni(OH)2/γ-NiOOH and β-Ni(OH)2/β-NiOOH redox couples are involved in the reversible reaction at positive electrode of NiMH batteries. The α-Ni(OH)2/γ-NiOOH process has a higher specific charge capacity than the β-Ni(OH)2/β-NiOOH. Despite the significantly better performance, α-Ni(OH)2 is not thermodynamically stable and more or less rapidly converted to β-Ni(OH)2, the material conventionally used in NiMH batteries. We expect to develop more efficient, robust and cost effective NiMH batteries than the presently used technology, utilizing new materials based on highly stabilized α-Ni(OH)2 nanoparticles with high specific charge/discharge capacity.

Name of CINEMA Fellow: Luiz H. Acauan
Name of CINEMA Research Mentor: Brian L. Wardle
Organization of CINEMA Research Mentor: Massachusetts Institute of Technology
CINEMA Energy Science Area of Research: Hybrid nano-materials, Optoelectronic properties

Low efficiencies in organic solar technology can be overcome by new approaches to materials chemistry within the morphology of the device layers and choice of semiconductors. In this project we pursue an architecture towards a hybrid organic solar cell with an active layer composed of three materials: a p-type organic polymer, vertically aligned carbon nanotubes (VACNT), undoped or Nitrogen-doped, decorated with TiO2 nanoparticles. In this configuration, a p-type polymer fills the interstitial space between the VACNT resulting in large interface area. The polymer assumes the role of absorbing light (mostly in the visible spectra) generating excitons. The TiO2 act as the acceptor material in its polymer interface, absorbing photons from UV region of the solar irradiation. The VACNT acts as a charge collector with a very high surface area and a well-oriented morphology towards the cathode.

This project aims to not only understand but also solve some of the main problems that involve flexible solar cells. By rationale design and nanomorphology control, including unique-to-MIT processing, a power efficiency up to 10% it is expected to be achieved.