Research Interests

A Nobel Prize winner in Physics, Richard Feynman, predicted decades ago that, “When we get to the very very small world--say circuits of several atoms--we have a lot of new things that would happen that represent completely new opportunities for design. Atoms on a small scale behave like nothing on a large scale, for they satisfy the law of quantum mechanics.”With diameters frequently less than 10 nm, carbon nanotubes fall into the size range where quantum effects become important, and this, combined with their unusual symmetries, has led researchers to predict many remarkable electronic, magnetic, and lattice properties which are quite different from those of their bulk counterparts. Currently, there are several funded nanoscience and nanotechnology research projects going on in Prof. Jiao’s group:

  1. CAREER: A Novel Approach for Controlled Fabrication of Micro-Gated Carbon Nanotube Field Emitter Arrays and Their Electrical Property Characterizations
    Source of Support: National Science Foundation (NSF)                
    Total Award Period Covered: 07/01/04 – 06/30/11

  2. REU Site: Research Experience in Nanotechnology and Sustainability
    Investigator: Jun Jiao (PI). This project is in collaboration with Dr. Erik Sanchez at the same department.
    Source of Support: National Science Foundation
    Total Award Period Covered: 03/01/10 – 02/31/13

  3. Biocompatible and Efficient Titanium-Dioxide Nanoparticle-Mediated Vaccine for Immotherapy Cancer Treatment
    This project is in collaboration with a colleague, Hong Ming Hu from Oregon Health and Science University (OHSU) and Providence Cancer Research Center.
    Source of Support: Office of Naval Research/Oregon Nanoscience and Microtechnologies Institute (ONR/ONAMI)
    Total Award Period Covered: 09/01/09 – 08/31/11

  4. Nanometrology Enabled Photo Stimulation of Nano-Electronics
    Source of Support: ONR/ONAMI
    Total Award Period Covered: 09/01/09 – 08/31/11

  5. Biological Fabrication of Photonic Crystal Thin Films for Enhanced Light Capture by Solar Cells
    This research is in collaboration with colleagues Greg Rorrer of Oregon State University and Bin Jiang of Portland State University
    Source of Support: ARL/ONAMI
    Total Award Period Covered: 09/01/09 – 08/31/11

  6. DNA Delivery Targeted to the Liver
    This project is in collaboration with colleagues (Michael Chapman, Markus Grompe, Eric Barklis, and Ujwal Shinde) from Oregon Health and Science University (OHSU).
    Support: Current
    Source of Support: ONR/ONAMI
    Total Award Period Covered: 09/01/09 – 08/31/11

  7. Phagocytes of metal oxide nanostructures by antigen presenting cells
    Investigator: Jun Jiao (PI). This project is in collaboration with a colleague, Hong Ming Hu from Oregon Health and Science University (OHSU) and Provident Cancer Research Center
    Source of Support: ONR/ONAMI
    Total Award Period Covered: 03/01/10 – 02/28/12

  8. A Novel Nanoparticle Core and Biopolymer Shell Antigen Targeting System for DCs
    This project is in collaboration with a colleague, Hong Ming Hu from Oregon Health and Science University (OHSU) and Provident Cancer Research Center.
    Source of Support: National Institute of Health (NIH)
    Total Award Period Covered: 04/01/11 – 03/31/13

  9. Optimization of Carbon Nanotube Based Chemical Sensors Through Micro-Raman Enabled Defect Analysis
    This project is in collaboration with Dr. Bin Jiang at the Mathematics Department. Portland State University
    Support: Pending
    Source of Support: National Science Foundation    
    Total Award Period Covered: 03/01/11 – 02/31/14

  10. Biological Fabrication of Photonic Crystal Thin Films for Enhanced Light Capture by Solar Cells
    (Funding source: Oregon Nanoscience and Microtechnologies Institute/ Army Research Laboratory)
    October 2009 – October 2010
    This research is in collaboration with colleagues Greg Rorrer from Oregon State University and Bin Jiang from Portland State University. The overall objective of this proposed research is to develop a fundamental understanding of bio-inspired photonic crystal thin films for enhanced solar energy conversion. Preliminary work suggests that a thin film of bio-inspired phonic crystal structures, when integrated into a photovoltaic device stack, has the potential to significantly enhance photon capture. We aim to control the interface between nanostructures and their surroundings for the biological fabrication of nanostructured thin films, and apply that focus to energy and energy storage to develop thin films that will enhance photovoltaic solar energy conversion through enhanced light capture.

  11. DNA Delivery Targeted to the Liver
    (Funding source: Oregon Nanoscience and Microtechnologies Institute/ Office of Naval Research)
    September 2009 – September 2010
    This research is in collaboration with colleagues (Michael Chapman, Markus Grompe, Eric Barklis, and Ujwal Shinde) from Oregon Health and Science University (OHSU). Our proposal’s research focuses on Adeno-associated virus (AAV), a small virus that is widespread in the human population, but does not cause disease. Its DNA genome is surrounded by a protective 250 Å diameter protein shell that is an icosahedrally-symmetric assembly of 60 capsid proteins that are responsible for attachment to receptors on susceptible cells. AAV is a leading candidate vector for gene therapy, used as a recombinant non-replicative form (rAAV), in which its replication and capsid genes are replaced with the foreign gene to be delivered into the nuclei of target cells. One of the tasks of this research is to use cryo-microscopy to characterize the samples. A new vitrobot cryo-sample preparation tool will be purchased through this grant and will be installed at the Center for Electron Microscope and Nanofabrication (CEMN) at PSU. The researchers will also use the state-of the-art electron microscopy facility at CEMN/PSU.

  12. Nanometrology Enabled Photo Stimulation of Nano-Electronics
    (Funding source: Oregon Nanoscience and Microtechnologies Institute/ Office of Naval Research)
    September 2009 – September 2010
    The objective of this research is to investigate the effect of photo stimulation on the electrical characteristics of single, isolated carbon nanotubes under environments with previously unattainable levels of control. The acquisition of a tunable laser coupled to a specifically designed fiber optic probe will enable this research. In an effort to understand the surface chemistry and environmental factors impacting the electrical performance of nanoelectronics, our group has developed several successful techniques for the fabrication, manipulation, and electrical characterization of CNT-based devices. To further this research we are systematically investigating the effect of photo stimulation on the performance of the CNT-based nanodevices by (1) designing and assembling the tunable laser probe and integrating this capability into an ultrahigh vacuum probe station and (2) investigating the effect of photo-stimulation on the SWCNT-FETs.

  13. Biocompatible and Efficient Titanium-Dioxide Nanoparticle-Mediated Vaccine for Immotherapy Cancer Treatment (Funding source: Oregon Nanoscience and Microtechnologies Institute/ Office of Naval Research)
    September 2009 – September 2010
    This research is in collaboration with a colleague, Hong Ming Hu, from Providence Cancer Center in Portland. Our long-term goal is to develop a biocompatible nanoparticle-based vaccine that efficiently triggers both innate and adaptive immune systems for advancing cancer therapy. The specific focus of this project is to design and fabricate TiO2 nanoparticles that can be conjugated with tumor antigens, immune stimulatory adjuvant, and imaging markers. We will then investigate their efficiency to elicit immune responses in vitro and in vivo.

  14. High Efficiency Bio-electrolytic Hydrogen Production from Biomass Using Nanostructure-Decorated Electrodes
    This project was in collaboration with Hong Liu at Oregon State University 
    Source of Support:  National Science Foundation (NSF)
    Total Award Period Covered:  09/01/08 – 08/31/10

  15. NIRT: Nanotube Based Structures for High Resolution Control of Thermal Transport
    (Funding source: National Science Foundation)
    August 2004 – July 2009
    This research is being undertaken in collaboration with Professors Cecilia Richards, David Bahr, Ching-Shih Chiang, and Robert Richards from Washington State University (WSU). The focus of this project is the use of carbon nanotubes (CNTs) to bridge scales from nanometers to micrometers, and the use of MEMS techniques to bridge scales from micrometers to millimeters. Manufacturing across six orders of length scales from nano to meso is made possible by utilizing the mixed-scale architectures of high aspect ration CNTs and two-dimensional lithographic-based low-aspect ration MEMS fabrication techniques. By tailoring the length of our fabricated structures to the specific functions required, we believe we can achieve superior properties and outstanding device/ material performance.

  16. NIRT: Whole-Cell Biosynthesis and Characterization of Nanostructured Metal Oxide Semiconductors
    (Funding source: National Science Foundation)
    August 2004 – July 2008
    This research is being undertaken in collaboration with Professors Gregory Rorrer and Chih-hung Chang of Oregon State University. The overall goal of this research and education program is to harness the nanobiochemcial machinery of diatom cell cultures to fabricate nanostructured metal oxide semiconductor materials that possess optoelectronic properties. Our research has three objectives: (1) develop perfusion-based bioreactor processing strategies for the biosynthesis of nanostructured metal oxide materials in diatom cell culture; (2) characterize the nanostructure and chemical structure of the composite metal oxide materials fabricated within the diatom cell; and (3) characterize the optoelectronic properties of the nanostructured metal oxide materials, after the appropriate post-processing of the biogenic inorganic material.

  17. Integration of Nanoscience and Nanotechnology Research, Education, and Outreach: Systematic Tailoring of Carbon Nanotubes to Designed Electronic Properties
    (Funding source: National Science Foundation)
    August 2002 – July 2005
    As we enter the 21st century, nanoscience and nanotechnology are becoming increasingly important and changing our everyday life. Advanced miniaturization will enable the development of ultra-small sensors and power sources, and communications, navigation and propulsion systems with very low mass and volume. In addition, nanotechnology presents a new range of opportunities to build device components and systems, embodying entirely new technology architectures. This project is aimed at developing an integrated research, education, and outreach program in nanoscience and technology at Portland State University, with an emphasis on carbon nanotube research. The major objectives of this research are: (1) to elucidate the growth mechanisms of nanotubes for different preparation parameters; (2) to develop a reliable procedure for preparing carbon nanotubes of controlled electronic properties; (3) to study the field-emission properties of carbon nanotubes and fabricate individual carbon nanotube field emitters, and (4) to provide training for both undergraduates and graduate students to explore cutting-edge research and gain advanced knowledge in nanoscience and nanotechnology through research and course-work opportunities.

    In order to bring the opportunities of physics and materials science research to various students, this program has a number of outreach activities. Through the research projects of this program, we are able to involve motivated high school and undergraduate students. In order to work on these projects, students are taught basic laboratory skills and are trained to operate some of PSU's sophisticated electron microscopy instruments. We also bring our work and knowledge into the community through an annual open house for the Girl Scouts, involvement with the Saturday Academy of Oregon's high school student Apprenticeships in Science and Engineering Program, and Portland High School District's Talented and Gifted Student Program.

  18. Systematic Investigation of Single-Walled Carbon Nanotubes Properties, Structure, Composition and Resistivity (Funding source: Intel Corporation)
    July 2003 – November 2009
    Single-walled carbon nanotubes (SWCNTs) are long, cylindrical carbon molecules. Their electronic properties depend on their structural details. CNTs can behave as either one-dimensional metals or semi-conductors, depending on how their graphite layers are wrapped. Theoretical calculations have predicted that the electrical properties of SWCNTs can rival, or even exceed, the best metals or semi-conductors currently known. Experimental efforts have demonstrated that CNTs have the potential to act as building blocks for flat-panel displays, nano-field effect transistors, nano-Schottky diodes, ion storage for batteries, etc. To achieve these technological promises, Dr. Jiao’s group at PSU and Dr. Dubin’s group at Intel Corporation are collaborating to systematically investigate correlations between the electronic properties, chemical compositions and nanostructures of SWCNTs for nano-device applications. The research efforts in Dr. Jiao’s group include (1) transmission electron microscopy (TEM) characterization of the internal structures of single-walled and multi-walled carbon nanotubes; (2) EDX analysis of chemical compositions of chemically modified CNTs; (3) scanning electron microscopy (SEM) characterization of the morphologies of CNTs; (4) atomic force microscopy (AFM) investigation of electronic properties of single-walled and multi-walled carbon nanotubes fabricated on silicon substrates.

  19. Position-Controlled Growth of Carbon Nanotubes
    (Funding source: Petroleum Research Foundation, American Chemical Society)
    June 2002 – May 2004
    This research project is aimed at developing a novel technology for synthesizing carbon nanotubes (CNTs) with controlled properties. The technique developed will allow us to synthesize nanotubes directly in various designed patterns. The nanofabrication process is based on a combination of focused ion beam (FIB) and chemical vapor deposition (CVD) techniques. In this process, arrays of conductive patterns were first deposited on silicon substrates by directing a gaseous compound (C9H16Pt) via the capillary needle-sized nozzles within a focused ion beam system. The substrates were then coated with catalyst and further modified by the FIB to localize the position of the catalyst. Finally, the growth of carbon nanotubes on the designed substrates was carried out by chemical vapor deposition of hydrocarbon gases. This fabrication technique has the advantage of positioning carbon nanotubes in well-controlled locations. This may open up opportunities for the direct synthesis of carbon nanotubes onto almost any substrate materials, thus allowing fabrication of carbon nanotube-based devices.

  20. CAREER: A Novel Approach for Controlled Fabrication of Micro-Gated Carbon Nanotube Field Emitter Arrays and Their Electrical Property Characterizations
    (Funding source: National Science Foundation)
    December 2003 – June 2009
    The high aspect ratio and small tip radius of curvature of carbon nanotubes (CNTs) make them especially suitable as sources for field emission. Recently, several reports have demonstrated that fabricating CNTs within micro-gated field emitter arrays (MG-FEAs) can reduce the required voltage and enable greater control over the emission current. The potential applications of gated CNT FEAs including flat panel displays, high frequency amplifiers, spacecraft propulsion systems, high voltage and high temperature electronics, portable x-ray sources, and multiple electron-beam lithography. The study of such triode-type CNT field emitters and emitter arrays, however, has been a less-publicized effort. The scarcity of reports on fabricating and characterizing micro-gated carbon nanotube field emitter arrays (MG-CNT-FEAs) is largely due to the complexity of making gated substrate arrays and the difficulty of controlling the growth of CNTs on the tops of substrate posts or on the bottoms of gated insulator-cell-arrays.

    Herein, we propose a program of research that exploits a novel hybrid approach of using the focused ion beam (FIB) and chemical vapor deposition (CVD) to fabricate MG-CNT-FEAs with better control. This proposed research will permit, for the first time, a fully- dry-etching process for fabricating micro-array substrates. The proposed technique, if it is successfully developed, will not only eliminate tedious wet chemistry processes but also provide the flexibility to fabricate MG-CNT-FEAs with various configurations. The main objectives of the proposed research program are, therefore, to (1) develop MG-CNT-FEAs of various configurations using a combined FIB and CVD technique; (2) characterize the field emission behaviors of the fabricated MG-CNT-FEAs; (3) optimize the fabrication procedures to maximize the MG-CNT-FEAs performance; (4) improve the techniques for growing high quality carbon nanotubes; and (5) explore procedures for the large-scale manufacture of MG-CNT-FEAs while scaling down the size of their single components (unit cells). In addition, the program creates a unique opportunity for blending the educational experience of graduate, undergraduate, and selected high school students with state-of-the-art fabrication technology and cutting edge research.

  21. The Advancement of Portland State University’s Multi-Disciplinary Materials Research
    (Funding source: M.J. Murdock Charitable Trust and Portland State University)
    August 2002 – July 2008
    iA fundamental understanding of the properties of a material starts with its thorough characterization. Morphology, crystal structure, chemical composition, interface structure, surfaces, and defects all have a strong influence on the properties and behavior of materials. Electron microscopy and microanalysis have proven indispensable to materials research and related disciplines, including physics, geology, mechanical engineering, electrical engineering, chemistry, and several life-science areas. The analytical potentials of the SEM and TEM equipped with an EDS are based on their abilities to identify the local chemical composition associated with the microstructure (ranging from crystalline to amorphous) and cellular to ultrastructure.

    With support from the University administration, Murdock Charitable Trust, local high-tech companies, and the combined efforts of the principal investigator (PI) Dr. Jiao and her colleagues, a newly established electron microscopy and microanalysis facility is now established at Portland State University (PSU). The facility consists of an FEI Tecnai F-20 field emission transmission electron microscope, a JEOL 2000FX TEM, an FEI Sirion field emission high resolution SEM, FEI 611 FIB system and a specimen preparation laboratory. The objective of this multi-user facility is to support the current expansion of research in the Departments of Physics, Geology, Chemistry, Biology, Environmental Science, Mechanical Engineering, and Electrical Engineering, to develop nationally competitive and externally fundable research programs, particularly in the areas of nanoscience and nanotechnology, and to position PSU as an essential partner with many local high-tech companies and elevate us to the next level in scientific and industrial partnerships. Dr. Jiao serves as the director for this state-of-the-art electron microscopy and microanalysis facility.

    Through this project, we have obtained a field-emission high-resolution transmission electron microscope equipped with an embedded digital STEM capability, EDX, GIF and EELS system. This instrumentation represents a crucial component in the multi-disciplinary materials research programs at Portland State University (PSU). Its unique capabilities will strengthen established research programs in such diverse technological areas as nanoscience and nanotechnology, geological and biomaterials, semiconductors and devices, metals and polymers. Atomic scale sub-nanostructures are known to play a dominant role in determining the performance of modern materials and devices. With the increasing demand for multi-component semiconductors, ceramics and composite materials, and the current trends toward miniaturization in virtually all areas of science and technology, the fundamental characterization of materials is of utmost importance.

    This high resolution field emission TEM is a tremendous asset to many disciplines at PSU and forms the nucleus of PSU’s centralized multi-user materials characterization facility, serving the needs of the university, local industry, and educational institutions in the community.