Eastern Illinois University :: Center for Clean Energy Research and Education (CENCERE)

Research Abstracts

Dr. He with EIU students

Molecular Engineering of Light-harvesting Materials for Solar Energy Conversion

Hongshan He, PhD Department of Chemistry, Eastern Illinois University, Charleston, IL 61920

Sun provides a tremendous amount of energy on Earth, and if we can convert a tiny amount of it to electricity, our energy shortage problem could be solved. Dye-sensitized solar cell is an important technology for cost-effective conversion of solar energy. One feature of this technology is to use dye-sensitized metal oxide nanomaterials to harvest sunlight and generate free electrons for the production of electricity. In this process, dyes adsorb on the surface of metal oxide nanomaterials. They first absorb the sunlight, then after several consecutive processes, including electron injection, migration, and dye regeneration, the electricity is produced. How broad of dyes absorb the sunlight and how strong they adsorb on metal oxide are crucial to power conversion efficiency and long-term stability of the devices. Dr. He and his students are using a molecular engineering approach to address these issues. It is expected that his research will advancing high efficiency and stable devices.

(1) Broaden light absorption capability of dyes. In an ideal situation, dye molecules should absorb a wide range of light from the visible to the near-infrared region. However, the current dyes only absorb up to 750 nm, leading to unsatisfactory power conversion efficiency for commercialization. The problem is also accompanied by discontinuous absorption characteristics, which causes poor incident photons to current efficiency at certain wavelengths. Both are unfavorable for obtaining high-efficiency dye-sensitized solar cells. To overcome these barriers, Dr. He and his students use theoretical modelling tools to identify potential dyes. Then they spend significant amount of time in laboratories to make those molecules, and test their photovoltaic performance in fabricated devices. Dr. He group is very interested in two types of molecules: porphyrins and boron-dipyrromethenes.

(2) Increase the binding strength of dyes to metal oxide nanomaterials. In order to make dye-sensitized solar cell operational for longer time, all components of the devices should show no or little alteration during its operation. However, devices will work only if the photosensitizers stay on the surface of the nanoparticles. State-of-the-art photosensitizers have weak binding strength is weak. The dye molecules will dissociate from metal oxide easily resulting poor stability of the devices. The approach that Dr. He and his students are using to tackle this problem is to replace conventional anchoring group with other multidentate ligands. One potential ligand is 8-hydroxylquinoline that shows very strong resistance to acidic and basic condition.

The research in Dr. He group is highly interdisciplinary. It spans from theoretical modeling, organic synthesis, spectroscopy, device engineering, fabrication, and characterization. It provides great opportunities for graduate and undergraduate students who have passion about renewable and sustainable energy.

New Gall Wasp Species Attacking Chestnut Trees: Dryocosmus zhuili n. sp. (Hymenoptera: Cynipidae) on Castanea henryi from Southeastern China

Dao-Hong Zhu, Central South University of Forestry and Technology, Changsha, Zhiwei Liu, Field Museum of Natural History, Chicago, Eastern Illinois University, Charleston, IL, Peng-Fei Lu, Central South University of Forestry and Technology, Changsha, Xiao-Hui Yang, Central South University of Forestry and Technology, Changsha, Cheng-Yuan Su, Central South University of Forestry and Technology, Changsha and Peter Liu, Eastern Illinois University, Charleston, IL

J. Insect Sci. (2015) 15(1): 156; DOI: 10.1093/jisesa/iev118

ABSTRACT. A new gall wasp species, Dryocosmus zhuili Liu et Zhu, is herein described from the southeastern Fujian province of China. The new species induces galls on trees of Henry’s chestnut, Castanea henryi, which is also a native host for the notorious Oriental chestnut gall wasp (OCGW, Dryocosmus kuriphilus Yasumatsu). D. zhuili overlaps with OCGW in emergence time and induces galls mor- phologically similar to that of OCGW on similar plant parts. In a previous study, we reported considerable divergence between mtDNA CO1 (mitochondrial DNA Cytochrome c oxidase subunit I) sequences of these wasps and the true OCGW wasps and suggested the exis- tence of a cryptic species. Herein, we conﬁrm the identity of the new species based on morphological and biological differences and provide a formal description. Although the new species is relatively easily separated from OCGW on basis of morphology, ﬁeld identiﬁ- cation involving the two species can still be problematic because of their small body size, highly similar gall morphology, and other life history traits. We further discussed the potential of the new species to be a pest for the chestnut industry and the consequences of ac- cidental introduction of this species into nonnative areas, especially with regard to the bisexual reproduction mode of the new species in contrast to the parthenogenetic reproduction mode of OCGW.

Improving Undergraduate Research Participation and Production in Technology Programs

Dr. Isaac Slaven, Dr. Austin Cheney

Abstract: Undergraduate students reap multiple benefits from participation in research. These include better job placement, increased interest in coursework, and a higher interest in graduate studies. This presentation discusses the techniques used to increase the participation and production of undergrads in independent and structured research programs, the successful outcomes, and the lessons learned.