Current Graduate Research Projects:

    • Hydrogen Sensor Based on Graphene on Ion Sensitive Field Effect Transistor (G-ISFET)

The research goals of this work are to develop graphene based H2 sensor AND predict the lifetime and reliability of this nanoscale material based device. To achieve these goals, efforts will be focused on developing and validating an aging protocol for graphene and studying the resulting changes in material properties.

The research goal of this works is to predict the lifetime and reliability of nanoscale materials, and is motivated by the fact that, to-date, there is very limited research on material aging at the nanoscale. However, preliminary research by the PIs indicates that even with as little as 30 min of aging in an extreme environment, a Si NW will undergo significant changes in diameter and oxide layer thickness. To achieve this goal, we are focusing our efforts on developing and validating an aging protocol for Si NWs and studying the resulting changes in material properties.

    • Mechanical properties estimation of biomedical samples using AFM-based nanoindentation

In this project, various biomedical samples, such as soft tissue scaffolds, protein µ-bubbles, are indented by an atomic force microscope in order to determine their Young’s modulus. Preparation of the biomedical samples is important as they have to be tested in liquid (PBS solution). Also these samples are extremely either soft or tiny, there is no suitable tools to carry out the indentation experiment except for AFM. After indenting the samples, raw data (force vs. distance) can be obtained from the microscope. Since all the parameters of the indenter (AFM tip) are known, it is able to plot the curve of force vs. sample indentation distance, according to which the Young’s modulus can be estimated using Hertz-Sneddon model. Current challenges include imaging the µ-bubbles without deflating them.

    • Development of CNT-ISFET system for pH sensing applications

The novelty of this project it the combination of Carbon nanotubes (CNTs) and Ion-Sensitive Field Effect Transistors (ISFETs). ISFETs have already been used to measure ion concentration in solution for years. Although so far CNT-ISFET concept has not been reported and explored yet, we believe there is huge potential for CNTs to greatly improve the performance of existing ISFETs pH sensors owing to their unique and excellent electrical properties, such as conductivity and current carrying capacity. Microelectrodes have been fabricated to test the alignment of CNTs using Dielectrophoresis (DEP), and AFM-based surface nanomachining (nanoscratching) has been performed on p-type Si substrates to create nanochannels for CNT-connecting between the drain and source. In the near future, ISFET and CNT-ISFET will be fabricated using MEMS fabrication techniques, and their performance for pH measurement will be compared.

    • Automate the temperature testing process for “ready to eat” cooked meat processing lines

The implementation of this automated temperature testing process involves three modules. The robotics module uses a vision guided robot manipulator to handle the samples. The robot arm, guided by machine vision cameras, picks the sample meat products from the conveyor and carries them over to the probing station where the probing of the samples is guided by another set of machine vision cameras. The probing is done with an electronic thermocouple probe which has data transfer capabilities. The database management module handles the collection, processing and transmission of data between all the components of the automated system. The controller module controls the entire process based on the results obtained from the probing process. The control system keeps the temperature of the cooked meat products within a specified range by varying the speed of the conveyor through the oven in real time. This project was done in three stages. The first stage involved building a test automated system in our lab. The system was built to scale in a carefully controlled environment for the purpose of obtaining all the relevant data needed for the implementation of the system on the industrial line. Then the results from the laboratory experiments were obtained, the industrial system was simulated using a robotic simulation software package (WorkSpace 5.2.4). The simulation provided relevant data while saving time and costly material. The final stage is the industrial implementation of the proposed automated system. At this time, having proven the technical and economic feasibility of the proposed system and having obtained all relevant data from the simulation (the most important of which are cycle time and throughput), the system is ready to be implemented. The implementation starts with our sponsors’ plant.

    • Nanocomposites-Physiochemical Analysis

Developed Nanocomposites using Conductive polymers and Carbon Nanotubes and analyzed their physiochemical properties using FTIR spectroscope and Atomic Force Microscope.

    • Nanocomposite electrode coating

Develop a technique to deposit the nanocomposites onto the electrodes.

    • Temperature effect on VACNFs” in collaboration with NASA Ames Research center

Investigated the effect of temperature on the Vertically Aligned Carbon Nanofibers dimensions.

    • Behavior of VACNFs in Extreme Environments” in collaboration with NASA Ames Research center

Studied the mechanical and physical properties of VACNFs in extreme environments to see if CNFs can survive outer space environmental conditions.

    • New Molecular Entity (NME) Identifier

Currently working on the development of microfluidic system for efficient identification of therapeutic drugs.