Primary Investigator: Dr. Wayne Archibald
Student Researchers: Darnel Allen, Phil Smith, David Paulius, Jewel Cumberbatch, Ykeshia Zamore
This project will demonstrate p-type doping of graphene by surface modification with tetrafluorotetracyanoquinodimethane (F4-TCNQ). F4-TCNQ has been widely used in organic light-emitting diodes to reduce the hole injection barrier by forming a narrow space-charge region near the metal contact, thereby improving device performance. Modifying the graphene surface with F4-TCNQ is therefore expected to favor electron transfer from graphene to F4-TCNQ molecules, leading to an electron accumulation layer in F4-TCNQ and a depletion layer in the graphene, thereby achieving p-type doping of the graphene.
The second task of this project is to investigate the effects of transition metals (TM) as potential electronic dopants in graphene using a chemical vapor deposition system. The doping studies will be complimented with carrier transport measurements. The project intends to find a correlation between the desired amount of doping, the concentration of atoms and their arrangement on the surface. A series of annealing experiments will be performed in order to determine whether or not the doping effect is still present. Lastly, it will be determined which mechanism is best suited for n-type and p-type doping and which set of conditions are most favorable for graphene to maintain its doped state.
Primary Investigator: Dr. Wayne Archibald, Assistant Professor and Director of the Caribbean Green Technology Center
Co-PI: Dr. Kala Fleming, Visiting Scientist
Student Researchers: Anthonios Doliotis and Kenisha Pascal
Heavy rainfall and loose, un-vegetated topsoil provide a lethal combination for erosion and sediment-ladden waters across watersheds in the US Virgin Islands (USVI). Consequently, the most developed areas are associated with the most impaired waters. Unrestrained development, limited cooperation among construction industry stakeholders, and poor monitoring and enforcement, are frequently lamented as key factors that exacerbate this situation. Less discussed and examined, however, are the human dimensions driving these observations. Instead of probing the root causes of behavior (human actions), most water resources studies in the Virgin Islands tend to focus solely on aggregate environmental indicators which in turn drive policy prescriptions that either recommend an engineering solution, add another layer of regulation or make overtures toward increased public education. In the end, many meetings, discussions and even research findings are directed toward the issue, but tangible outcomes that address the root cause in a meaningful way are limited.
PI: Dr. Wayne Archibald
Student Researcher: Michelle Gordon
The burning of fossil fuels to generate energy for transportation, electricity along with other residential, commercial and industrial processes has resulted in copious emissions of greenhouse gases (GHGs). The emissions have led to an enhancement of the atmospheric greenhouse effect and an attendant increase in global surface temperature. Two of the most significant effects of these are global climate change and sea level rise. The United States, being a signatory to the United Nations Convention on Climate Change (UNFCCC), therefore has an obligation to reduce its emission of GHG through removal by sinks or reduction from sources. Given the vulnerability of small islands, the US Virgin Islands in particular has a responsibility to act.
A number of restaurants, hotels and cruise ships which operate in St. Thomas, USVI, produce significant quantities of waste oil. The Waste oil disposal poses a number of challenges for both local and municipal waste management. Being non-biodegradable and combustible, improper waste oil disposal may create both a public hazard and eventual environmental degradation. The waste oil is a potential fuel source. The local Energy and Environmental Protection Committee in St. Thomas has recently voted unanimously to approve a cooking oil collection certification program in the territory which will enhance any initiative to convert the oil to a valuable energy resource.
Waste vegetable oil (WVO) when converted to biodiesel is regarded as renewable and eco-friendly. WVO is a carbon neutral or carbon positive fuel. The carbon dioxide (CO2) emitted by burning WVO is not "new" CO2 being put into the atmosphere. Vegetable oil is created by plants; the carbon dioxide emitted was originally pulled from the atmosphere by the plant. As a consequence the fuel from WVO is regarded as "carbon neutral”, and some even regard it as being “carbon positive” emitting less carbon than it absorbs from the atmosphere.
Based on the success of the Alternative Energy programs at The UWI and the biodiesel project, a partnership is being forged between CGTC and The UWI which will see a similar approach being pursued via this scoping mission. Under this partnership The UWI, through the Departments of Physics and Chemistry will support and collaborate with CGTC to improve the lives of USVI citizens through joint efforts in curriculum development and the promotion of the use of alternative fuels and environmentally sustainable transport. This collaboration presents a viable opportunity to develop and implement a project for converting WVO, a waste product that requires safe disposal, into biodiesel, a form of diesel fuel that is readily manufactured from used or freshly produced vegetable oil or animal fat using technology that is widely available and readily accessible. Additionally, this project will attempt, through training and capacity building at the community and school-level, to target St. Thomas citizens in an effort to highlight the importance of environmental protection and enhance involvement in the climate change mitigation process.