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Carbon nanomaterials have caught tremendous attention in the last few decades due to their unique physical and chemical properties. Tremendous effort has been made to develop new synthesis techniques for carbon nanomaterials and investigate their properties for different applications. In this work, carbon nanospheres (CNSs), carbon foams (CF), and single-walled

Carbon nanomaterials have caught tremendous attention in the last few decades due to their unique physical and chemical properties. Tremendous effort has been made to develop new synthesis techniques for carbon nanomaterials and investigate their properties for different applications. In this work, carbon nanospheres (CNSs), carbon foams (CF), and single-walled carbon nanotubes (SWNTs) were studied for various applications, including water treatment, energy storage, actuators, and sensors.

A facile spray pyrolysis synthesis technique was developed to synthesize individual CNSs with specific surface area (SSA) up to 1106 m2/g. The hollow CNSs showed adsorption of up to 300 mg rhodamine B dye per gram carbon, which is more than 15 times higher than that observed for conventional carbon black. They were also evaluated as adsorbents for removal of arsenate and selenate from water and displayed good binding to both species, outperforming commercial activated carbons for arsenate removal in pH > 8. When evaluated as supercapacitor electrode materials, specific capacitances of up to 112 F/g at a current density of 0.1 A/g were observed. When used as Li-ion battery anode materials, the CNSs achieved a discharge capacity of 270 mAh/g at a current density of 372 mA/g (1C), which is 4-fold higher than that of commercial graphite anode.

Carbon foams were synthesized using direct pyrolysis and had SSA up to 2340 m2/g. When used as supercapacitor electrode materials, a specific capacitance up to 280 F/g was achieved at current density of 0.1 A/g and remained as high as 207 F/g, even at a high current density of 10 A/g.

A printed walking robot was made from common plastic films and coatings of SWNTs. The solid-state thermal bimorph actuators were multifunctional energy transducers powered by heat, light, or electricity. The actuators were also investigated for photo/thermal detection. Electrochemical actuators based on MnO2 were also studied for potential underwater applications.

SWNTs were also used to fabricate printable electrodes for trace Cr(VI) detection, which displayed sensitivity up to 500 nA/ppb for Cr(VI). The limit of detection was shown to be as low as 5 ppb. A flow detection system based on CNT/printed electrodes was also demonstrated.
ContributorsWang, Chengwei, Ph.D (Author) / Chan, Candace K. (Thesis advisor) / Tongay, Sefaattin (Committee member) / Wang, Qing Hua (Committee member) / Seo, Dong (Committee member) / Arizona State University (Publisher)
Created2015
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Description
Since the discovery of graphene, two dimensional materials (2D materials) have become a focus of interest for material research due to their many unique physical properties embedded in their 2D structure. While they host many exciting potential applications, some of these 2D materials are subject to environmental instability issues induced

Since the discovery of graphene, two dimensional materials (2D materials) have become a focus of interest for material research due to their many unique physical properties embedded in their 2D structure. While they host many exciting potential applications, some of these 2D materials are subject to environmental instability issues induced by interaction between material and gas molecules in air, which poses a barrier to further application and manufacture. To overcome this, it is necessary to understand the origin of material instability and interaction with molecules commonly found in air, as well as developing a reproducible and manufacturing compatible method to post-process these materials to extend their lifetime. In this work, the very first investigation on environmental stability on Te containing anisotropic 2D materials such as GaTe and ZrTe3 is reported. Experimental results have demonstrated that freshly exfoliated GaTe quickly deteriorate in air, during which the Raman spectrum, surface morphology, and surface chemistry undergo drastic changes. Environmental Raman spectroscopy and XPS measurements demonstrate that H2O molecules in air interact strongly on the surface while O2, N2, and inert gases don't show any detrimental effects on GaTe surface. Moreover, the anisotropic properties of GaTe slowly disappear during the aging process. To prevent this gas/material interaction based surface transformation, diazonium based surface functionalization is adopted on these Te based 2D materials. Environmental Raman spectroscopy results demonstrate that the stability of functionalized Te based 2D materials exhibit much higher stability both in ambient and extreme conditions. Meanwhile, PL spectroscopy, angle resolved Raman spectroscopy, atomic force microscopy measurements confirm that many attractive physical properties of the material are not affected by surface functionalization. Overall, these findings unveil the degradation mechanism of Te based 2D materials as well as provide a way to significantly enhance their environmental stability through an inexpensive and reproducible surface chemical functionalization route.
ContributorsYang, Sijie (Author) / Tongay, Sefaattin (Thesis advisor) / Gould, Ian (Thesis advisor) / Trovitch, Ryan (Committee member) / Ghirlanda, Giovanna (Committee member) / Arizona State University (Publisher)
Created2017
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Description
There has been a surge in two-dimensional (2D) materials field since the discovery of graphene in 2004. Recently, a new class of layered atomically thin materials that exhibit in-plane structural anisotropy, such as black phosphorous, transition metal trichalcogenides and rhenium dichalcogenides (ReS2), have attracted great attention. The reduced symmetry in

There has been a surge in two-dimensional (2D) materials field since the discovery of graphene in 2004. Recently, a new class of layered atomically thin materials that exhibit in-plane structural anisotropy, such as black phosphorous, transition metal trichalcogenides and rhenium dichalcogenides (ReS2), have attracted great attention. The reduced symmetry in these novel 2D materials gives rise to highly anisotropic physical properties that enable unique applications in next-gen electronics and optoelectronics. For example, higher carrier mobility along one preferential crystal direction for anisotropic field effect transistors and anisotropic photon absorption for polarization-sensitive photodetectors.

This dissertation endeavors to address two key challenges towards practical application of anisotropic materials. One is the scalable production of high quality 2D anisotropic thin films, and the other is the controllability over anisotropy present in synthesized crystals. The investigation is focused primarily on rhenium disulfide because of its chemical similarity to conventional 2D transition metal dichalcogenides and yet anisotropic nature. Carefully designed vapor phase deposition has been demonstrated effective for batch synthesis of high quality ReS2 monolayer. Heteroepitaxial growth proves to be a feasible route for controlling anisotropic directions. Scanning/transmission electron microscopy and angle-resolved Raman spectroscopy have been extensively applied to reveal the structure-property relationship in synthesized 2D anisotropic layers and their heterostructures.
ContributorsChen, Bin, 1968- (Author) / Tongay, Sefaattin (Thesis advisor) / Bertoni, Mariana (Committee member) / Chang, Lan-Yun (Committee member) / Arizona State University (Publisher)
Created2018
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Description
Layer structured two dimensional (2D) semiconductors have gained much interest due to their intriguing optical and electronic properties induced by the unique van der Waals bonding between layers. The extraordinary success for graphene and transition metal dichalcogenides (TMDCs) has triggered a constant search for novel 2D semiconductors beyond them. Gallium

Layer structured two dimensional (2D) semiconductors have gained much interest due to their intriguing optical and electronic properties induced by the unique van der Waals bonding between layers. The extraordinary success for graphene and transition metal dichalcogenides (TMDCs) has triggered a constant search for novel 2D semiconductors beyond them. Gallium chalcogenides, belonging to the group III-VI compounds, are a new class of 2D semiconductors that carry a variety of interesting properties including wide spectrum coverage of their bandgaps and thus are promising candidates for next generation electronic and optoelectronic devices. Pushing these materials toward applications requires more controllable synthesis methods and facile routes for engineering their properties on demand.

In this dissertation, vapor phase transport is used to synthesize layer structured gallium chalcogenide nanomaterials with highly controlled structure, morphology and properties, with particular emphasis on GaSe, GaTe and GaSeTe alloys. Multiple routes are used to manipulate the physical properties of these materials including strain engineering, defect engineering and phase engineering. First, 2D GaSe with controlled morphologies is synthesized on Si(111) substrates and the bandgap is significantly reduced from 2 eV to 1.7 eV due to lateral tensile strain. By applying vertical compressive strain using a diamond anvil cell, the band gap can be further reduced to 1.4 eV. Next, pseudo-1D GaTe nanomaterials with a monoclinic structure are synthesized on various substrates. The product exhibits highly anisotropic atomic structure and properties characterized by high-resolution transmission electron microscopy and angle resolved Raman and photoluminescence (PL) spectroscopy. Multiple sharp PL emissions below the bandgap are found due to defects localized at the edges and grain boundaries. Finally, layer structured GaSe1-xTex alloys across the full composition range are synthesized on GaAs(111) substrates. Results show that GaAs(111) substrate plays an essential role in stabilizing the metastable single-phase alloys within the miscibility gaps. A hexagonal to monoclinic phase crossover is observed as the Te content increases. The phase crossover features coexistence of both phases and isotropic to anisotropic structural transition.

Overall, this work provides insights into the controlled synthesis of gallium chalcogenides and opens up new opportunities towards optoelectronic applications that require tunable material properties.
ContributorsCai, Hui, Ph.D (Author) / Tongay, Sefaattin (Thesis advisor) / Dwyer, Christian (Committee member) / Zhuang, Houlong (Committee member) / Arizona State University (Publisher)
Created2018
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Description
The National Basketball Association (NBA) is one of the Big Four Sporting Leagues of US Professional Sports. In recent years, the NBA has enjoyed milestone seasons in both attendance and television ratings, resulting in steady increases to both, over the previous decade. (Morgan, 2017) This surge can be attributed in

The National Basketball Association (NBA) is one of the Big Four Sporting Leagues of US Professional Sports. In recent years, the NBA has enjoyed milestone seasons in both attendance and television ratings, resulting in steady increases to both, over the previous decade. (Morgan, 2017) This surge can be attributed in part to the integration of "cultural recognition" initiatives and the overall message of inclusivity on the part of NBA franchises, with their respective promotions and advertisements such as television, social media, radio, etc. Heritage Nights, such as "Noche Latina," among other variants in the NBA, typically feature culturally influenced changes to team logos, giveaways, and other consumer offerings. In markets where Hispanics make up a significant percentage of the fan-base, such as Phoenix, NBA franchises such as the Phoenix Suns must ascertain the financial or perceptual impacts, associated with risks of stereotyping, offending or otherwise unintentionally alienating different categories of fans. To this end, data was collected from the local NBA franchises' fanbase, specifically Phoenix Suns season-ticket holders, and was statistically checked for significant relationships between both categories of fans and several different variables. This analysis found that only $192K in revenue is being missed through the investment of Heritage Nights, and that fan perceptions of stereotypical or offensive giveaways and practices have no significant effect on game or event attendance, despite the stereotypes toward giveaways and practices still being present. Implications of this study provide possible next steps for the Suns and continue to widen the scope of demographical sports marketing both in professional basketball and beyond.
ContributorsGibbens, Patrick Alexander (Author) / Eaton, John (Thesis director) / McIntosh, Daniel (Committee member) / Department of Supply Chain Management (Contributor) / School of Music (Contributor) / Department of Marketing (Contributor) / W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This paper is intended to identify a correlation between the winning percentage of sports teams in the four major professional sports leagues in the United States and the GDP per capita of their respective cities. We initially compiled fifteen years of franchise performance along with economic data from the Federal

This paper is intended to identify a correlation between the winning percentage of sports teams in the four major professional sports leagues in the United States and the GDP per capita of their respective cities. We initially compiled fifteen years of franchise performance along with economic data from the Federal Reserve Bank of St. Louis to analyze this relationship. After converting the data into a language recognized by Stata, the regression tool we used, we ran multiple regressions to find relevant correlations based off of our inputs. This paper will show the value of the economic impact of strong or weak performance throughout various economic cycles through data analysis and conclusions drawn from the results of the regression analysis.
ContributorsAndl, Tyler (Co-author) / Shirk, Brandon (Co-author) / Goegan, Brian (Thesis director) / Eaton, John (Committee member) / School of Accountancy (Contributor) / Department of Finance (Contributor) / Department of Supply Chain Management (Contributor) / Department of Information Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
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Description
The vastly growing field of supercomputing is in dire need of a new measurement system to optimize JMRAM (Josephson junction magnetoresistive random access memory) devices. To effectively measure these devices, an ultra-low-noise, low cost cryogenic dipping probe with a dynamic voltage range is required. This dipping probe has been designed

The vastly growing field of supercomputing is in dire need of a new measurement system to optimize JMRAM (Josephson junction magnetoresistive random access memory) devices. To effectively measure these devices, an ultra-low-noise, low cost cryogenic dipping probe with a dynamic voltage range is required. This dipping probe has been designed by ASU with <100 nVp-p noise, <10 nV offsets, 10 pV to 16 mV voltage range, and negligible thermoelectric drift. There is currently no other research group or company that can currently match both these low noise levels and wide voltage range. Two different dipping probes can be created with these specifications: one for high-use applications and one for low-use applications. The only difference between these probes is the outer shell; the high-use application probe has a shell made of G-10 fiberglass for a higher price, and the low-use application probe has a shell made of AISI 310 steel for a lower price. Both types of probes can be assembled in less than 8 hours for less than $2,500, requiring only soldering expertise. The low cost and short time to create these probes makes wide profit margins possible. The market for these cryogenic dipping probes is currently untapped, as most research groups and companies that use these probes build their own, which allows for rapid business growth. These potential consumers can be easily reached by marketing these probes at superconducting conferences. After several years of selling >50 probes, mass production can easily become possible by hiring several technicians, and still maintaining wide profit margins.
ContributorsHudson, Brooke Ashley (Author) / Adams, James (Thesis director) / Anwar, Shahriar (Committee member) / Materials Science and Engineering Program (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
The ability to draft and develop productive Major League players is vital to the success of any MLB organization. A core of cost-controlled, productive players is as important as ever with free agent salaries continuing to rise dramatically. In a sport where mere percentage points separate winners from losers at

The ability to draft and develop productive Major League players is vital to the success of any MLB organization. A core of cost-controlled, productive players is as important as ever with free agent salaries continuing to rise dramatically. In a sport where mere percentage points separate winners from losers at the end of a long season, any slight advantage in identifying talent is valuable. This study examines the 2004-2008 MLB Amateur Drafts in order to analyze whether certain types of prospects are more valuable selections than others. If organizations can better identify which draft prospects will more likely contribute at the Major League level in the future, they can more optimally spend their allotted signing bonus pool in order to acquire as much potential production as possible through the draft. Based on the data examined, during these five drafts high school prospects provided higher value than college prospects. While college players reached the Majors at a higher rate, high school players produced greater value in their first six seasons of service time. In the all-important first round of the draft, where signing bonuses are at their largest, college players proved the more valuable selection. When players were separated by position, position players held greater expected value than pitchers, with corner infielders leading the way as the position group with the highest expected value. College players were found to provide better value than high school players at defensively demanding positions such as catcher and middle infield, while high school players were more valuable among outfielders and pitchers.
ContributorsGildea, Adam Joseph (Author) / Eaton, John (Thesis director) / McIntosh, Daniel (Committee member) / Department of Economics (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Abstract My documentary is about the concussion detection study with Arizona State Football, Translational Genomics Research Institute (TGen), Riddell and the Barrow Neurological Institute. Football players voluntarily participate in the study that aims to identify a biomarker released from the brain to identify if a player has suffered from a

Abstract My documentary is about the concussion detection study with Arizona State Football, Translational Genomics Research Institute (TGen), Riddell and the Barrow Neurological Institute. Football players voluntarily participate in the study that aims to identify a biomarker released from the brain to identify if a player has suffered from a concussion. The study uses blood, urine and saliva samples, along with head impact data from Riddell's Sideline Response System. The study is also focusing on the impact of sub-concussive hits and the effects. According to the Barrow Neurological Institute, 84% of respondents believe concussions are "a serious medical condition," and a third of Valley parents will not let their children play football. I interviewed an ASU football player who participated in the study and found out about his experiences with concussions. The severity of concussions has received a lot of attention in recent years, and this study hopes to mitigate concussions symptoms and the fear of concussions. According to the 2015 NFL Health and Safety Report, since 2012 the NFL reported concussions were down by 35%. I interviewed the TGen leaders of the study and the neurologist at the Barrow Concussion and Brain Injury center involved in the study to find out how they plan to find a biomarker and use it to develop an objective way to diagnose concussions. An example of a possible objective test is a mouthguard that changes from clear to blue after a player sustained a hit that resulted in a concussion. The 2015-2016 ASU football season marked the study's third year of research. At the time of my documentary, the study had no timeline to release data.
ContributorsSeki, Katryna Marie (Author) / Lodato, Mark (Thesis director) / Kurland, Brett (Committee member) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Each year, a select few minor league baseball players are chosen to attend the Arizona Fall League, a development league within Major League Baseball that hones the next generation of players, coaches, managers, and even umpires. These players make up the top talent currently in the minor leagues from each

Each year, a select few minor league baseball players are chosen to attend the Arizona Fall League, a development league within Major League Baseball that hones the next generation of players, coaches, managers, and even umpires. These players make up the top talent currently in the minor leagues from each of Major League Baseball's 30 organizations. Of the thousands in the minors, just seven players from each organization can go to this extra six-week season, and learn to play alongside the best future talent the sport has to offer. On Deck: Inside the Arizona Fall League is a short documentary that looks at some of these players, as they continue their baseball journey that they hope leads them one day to the Majors. The documentary can be viewed online at https://youtu.be/jkggYiDtn14 or nicolesheraefox.com
ContributorsFox, Nicole Sherae (Author) / Lodato, Mark (Thesis director) / Kurland, Brett (Committee member) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05