Research Area
Simulation-Based Pedagogical Approach in Chemistry Education for All Students to Succeed in STEM
The Project Simulation-Based Pedagogical Approach in Chemistry Education for All Students to Succeed in STEM (SPACE) aims to develop, implement, validate, and disseminate a program that will support the advancement of undergraduate students’ fundamental understanding of chemical reactions and its application in solving advanced scientific problems using training in computational modeling and simulation skills with a pedagogical approach that includes guided inquiry-based learning. The project will unfold over two years in two implementations to pilot test the program, which will be refined for improvement from Year 1 to 2. Through the two implementations, the efficacy, content quality, usability, and feasibility of the program will be comprehensively evaluated using a set of instruments to examine its promises for future adaptation and replication at an institutional level. The intent of the SPACE is to be a stepping stone to build the capacity of Hispanic-serving institutions (HSIs) to enrich the quality of undergraduate STEM education through interdisciplinary collaborative research effort.
Computational Design of High-performance liquid fuels for the hypersonic scramjet aircraft
In scramjet aircraft, we posited two major concerns that make the combustion process non-trivial: high temperature of engine room and high speed of fuels. To address these issues, Dr. Hong’s group is focusing on developing novel hydrocarbon-based fuel mixtures that are fully functional as scramjet fuels at extreme conditions. Results combining experiments and computer simulations showed that hydrocarbon fuels loaded on functionalized graphene sheets acted as catalytic dehydrogenation of fuels and improved the energetic performance
Improved Combustion Performance of Aluminum Nanoparticles by SURFACE Coatings
Metal combustion has received a great amount of interest as metal nanoparticles have been routinely synthesized and characterized. Metal nanoparticles are known to have high specific surface area (high reactivity), increased catalytic activity, and low melting temperatures. As such, metal nanoparticles are considered novel energetic materials for a wide range of energy-transfer applications ranging from catalytic reactions to combustion processes. In particular, aluminum nanoparticles (ANPs) are the most promising materials for those applications, owing to their Earth abundance, low toxicity, and high specific energy density. However, ANPs are readily sintered and oxidized at room temperature prior to combustion reactions, degrading the energetic performance. In order to revolve those problems, organic coating on the ANPs has been proposed. Organic coating has the following advantages: 1) Organic coated ANPs are only reactive at high temperatures; 2) Organic coated ANPs have a hydrophobic characteristic; 3) Organic coatings serve as additional energy sources. While many researchers have investigated the effects of organic coating on combustion performance of ANPs experimentally, a molecular-level understanding for chemical reactions during sintering and thermal processing of bare and organic coated ANPs at low/high temperatures remains unclear.
Our research group uses the well-developed and validated ReaxFF force field to investigate:
1) sintering behaviors of untreated and surface coated ANPs;
2) combustion (oxidation) performance of untreated and organic coated ANPs;
3) reaction mechanisms for improved combustion performance by a differnt types of coatings (using hydrocarbon and/or silane).
Mechanically strengthened glass-ceramic materials for aircraft applications
The goal of this research work is to design ultra-high strength glass-ceramic materials for aircraft windshields and windows application. In this project, Dr. Hong’s group found that the insertion of glass crystal grains into the parent glass will successfully improve the mechanical properties of these glass materials because those crystal grains can hinder crack initiation and propagation along the amorphous glass (see Figure 3 for computational models). Additionally, this topic could be used to strengthen a collaboration network platform among CSUB and local engineering companies in Lancaster and Palmdale (e.g., Northrop Grumman, Lockheed Martin, and Boeing) to uniquely prepare students in the area of high-performance aerospace materials, to meet the current needs of aerospace industry, and to increase the research capacity of CSUB.
Mechanistic Study of Synthesis of Novel 2D Materials
Layered materials consisting of transition metal dichalcogenides (TMDCs) are attracting great attention due not only to their outstanding electronic, optical, magnetic and chemical properties, but also to the possibility of tuning these properties in desired ways by building van der Waal heterostructures composed of unlimited combinations of atomically thin layers. The key enabler to bring this fascinating technology into mass production is chemical vapor deposition (CVD) synthesis. Deciphering selection rules for different growth scenarios would enable predictions of optimized environmental parameters and growth factors, which remains elusive. The major roadblock is the lack of knowledge about initial reaction pathways.
Our research group investigates initial sulfidation pathways of a MoO3 surface during CVD growth of an archetypal TMDC material, MoS2, using reactive molecular dynamics (RMD) simulations based on a reactive force field (ReaxFF). In addition to MoS2 layers, mechanistic study of synthesis of other 2D Materials will be conducted.