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- All Subjects: Entrepreneurship
- Creators: Barrett, The Honors College
- Creators: Tongay, Sefaattin
Description
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.
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
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 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
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 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.
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
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 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.
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
Description
After freelancing on my own for the past year and a half, I have realized that one of the biggest obstacles to college entrepreneurs is a fear or apprehension to sales. As a computer science major trying to sell my services, I discovered very quickly that I had not been prepared for the difficulty of learning sales. Sales get a bad rap and very often is the last thing that young entrepreneurs want to try, but the reality is that sales is oxygen to a company and a required skill for an entrepreneur. Due to this, I compiled all of my knowledge into an e-book for young entrepreneurs starting out to learn how to open up a conversation with a prospect all the way to closing them on the phone. Instead of starting from scratch like I did, college entrepreneurs can learn the bare basics of selling their own services, even if they are terrified of sales and what it entails. In this e-book, there are tips that I have learned to deal with my anxiety about sales such as taking the pressure off of yourself and prioritizing listening more than pitching. Instead of trying to teach sales expecting people to be natural sales people, this e-book takes the approach of helping entrepreneurs that are terrified of sales and show them how they can cope with this fear and still close a client. In the future, I hope young entrepreneurs will have access to more resources that handle this fear and make it much easier for them to learn it by themselves. This e-book is the first step.
ContributorsMead, Kevin Tyler (Author) / Sebold, Brent (Thesis director) / Kruse, Gabriel (Committee member) / Computer Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This study explores the best known practices of small businesses from different entrepreneurs' perspectives and attempts to address the question: are there consistencies between different entrepreneurs' approaches to establishing and growing a business? Ten entrepreneurs from a variety of business types (product and service) were interviewed using a consistent question template that asked questions regarding financing, business strategy (and scalability), interpersonal forces, innate qualities, partnerships, and resources. The primary overlaps between these businesses are with regard to the confluence between personal risk and business strategy, the risk of working with friends and family, the capacity to scale relative to special content knowledge or process knowledge, and partnerships
etworking.
etworking.
ContributorsCole, Chandler William (Author) / Kellso, James (Thesis director) / Gilmore, Bruce (Committee member) / Department of Supply Chain Management (Contributor) / Department of Finance (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
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 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
Description
Women dominate in terms of purchasing power and spending. They hold 60 percent of all US personal income, and those aged 50 years or older have a combined net worth of approximately $19 trillion. Of this group, women between 50 and 70 years old, in particular, are the biggest spenders (Barmann, 2014). More important than their spending power, however, is how satisfied (or dissatisfied) they are with their current purchases. Though women make 85 percent of all consumer purchases, 91 percent of women say, "...advertisers don't understand them," (Barmann, 2014). This makes sense, considering that 50 percent of the products marketed to men are actually purchased by women (Barmann, 2014). Successfully targeting women, especially Baby Boomers (women between 52 and 70 years old), would be a lucrative endeavor, and to better understand the unmet needs of that demographic, exploratory research was needed. In-depth interviews of Baby Boomer women reveals a problem that \u2014 even on a macro level \u2014 has gone unresolved, and has perhaps worsened, throughout written history: the Generation Gap (Bengtson, 1970). To illustrate the depth of the problem, there exist starkly different impressions of younger generations, namely Millennials (born between 1980 and 1995). According to The New Generation Gap by Neil Howe and William Strauss (1992), Baby Boomers view Millennials as unintelligent, entitled "pleasure beasts." In Millennials Rising, also by Howe and Strauss (2000), Millennials are characterized as a generation that is, "...beginning to manifest a wide array of positive social habits that older Americans no longer associate with youth, including a new focus on teamwork, achievement, modesty, and good conduct." These contradictory opinions further support the substantial misunderstanding between generations that surfaced during in-depth interviews. Using the results of in-depth interviews and follow-up questions for idea validation, this thesis presents a potential method for "closing the gap." The goal of this business offering is not to homogenize older and younger generations of women; the goal is to cultivate empathy and connection \u2014 Intergenerational Cohesion \u2014 between them.
ContributorsSeefus, Cole Hawk Gillette (Author) / Gray, Nancy (Thesis director) / Giard, Jacques (Committee member) / Department of Management (Contributor) / Department of Marketing (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Aventure is the newest contemporary luxury men and women’s apparel and accessories boutique in Arizona. The boutique will be located in Downtown Scottsdale, specifically in McKellips Plaza conveniently located near Scottsdale Fashion Square. Aventure is the first of its kind in the Phoenix Metropolitan Area, providing Millennial fashion fanatics with a destination that fills the empty void in the city’s growing fashion scene. At Aventure, we bridge the gap between pop culture, streetwear, and high-fashion. Through our mantra ‘Redefining the Luxury Retail Experience,’ we aim is to promote expression of one’s self to the fullest extent through style.
‘Aventure,’ which means “experience” or “adventure” in French, defines this upscale boutique and its essence of inclusion. This store does not aim to be your traditional retailer; instead, Aventure aims to build a community within and around the store for individuals with similar styles and passion for fashion. At the moment, the city of Scottsdale (and the Metro Phoenix area as a whole) does not have its own identity in the fashion world. There is no reason why Metro Phoenix cannot, with time, become more recognized in the global fashion community. With an array of exclusive luxury merchandise and an urban atmosphere, Aventure aims to pioneer the Valley’s establishment on the national high-end fashion scene.
The boutique is a result of the vision of its founder Ahmed Imam. Ahmed is a graduating Honors student at Arizona State Univeristy’s W.P. Carey School of Business, pursuing concurrent degrees in Finance and Business Entrepreneurship. Having been passionate about fashion for as long as he can remember, Ahmed will leverage his connections to the industry and excellent understanding of the Metro Phoenix market to turn Aventure into a hallmark of the community. Through his professional experience and educational background, Ahmed also brings the necessary knowledge and skills to the table to effectively run a startup.
The retail industry is experiencing steady growth, with the luxury goods sector expected to perform very well in the coming years. Using market-based sales forecasting, Aventure is estimated to break even by the third year of operations. Sales are expected to grow 20 percent after Year 1, and grow 5 percent thereafter. Net operating income of $83,643 is estimated in Year 1, growing to $141,351 by the end of Year 3. Overall, total startup expenses are estimated to be $206,574, made up of investments from owners and a term loan from Bank of America. The owner investment will be used to cover capital equipment, location, and administrative expenses. These include furniture, equipment, machinery, rent, utility, legal and accounting fees, prepaid insurance, and other expenses. The majority of the term loan will be used to finance opening inventory and advertising expenses, with the rest going towards cash on the balance sheet to ensure liquidity.
‘Aventure,’ which means “experience” or “adventure” in French, defines this upscale boutique and its essence of inclusion. This store does not aim to be your traditional retailer; instead, Aventure aims to build a community within and around the store for individuals with similar styles and passion for fashion. At the moment, the city of Scottsdale (and the Metro Phoenix area as a whole) does not have its own identity in the fashion world. There is no reason why Metro Phoenix cannot, with time, become more recognized in the global fashion community. With an array of exclusive luxury merchandise and an urban atmosphere, Aventure aims to pioneer the Valley’s establishment on the national high-end fashion scene.
The boutique is a result of the vision of its founder Ahmed Imam. Ahmed is a graduating Honors student at Arizona State Univeristy’s W.P. Carey School of Business, pursuing concurrent degrees in Finance and Business Entrepreneurship. Having been passionate about fashion for as long as he can remember, Ahmed will leverage his connections to the industry and excellent understanding of the Metro Phoenix market to turn Aventure into a hallmark of the community. Through his professional experience and educational background, Ahmed also brings the necessary knowledge and skills to the table to effectively run a startup.
The retail industry is experiencing steady growth, with the luxury goods sector expected to perform very well in the coming years. Using market-based sales forecasting, Aventure is estimated to break even by the third year of operations. Sales are expected to grow 20 percent after Year 1, and grow 5 percent thereafter. Net operating income of $83,643 is estimated in Year 1, growing to $141,351 by the end of Year 3. Overall, total startup expenses are estimated to be $206,574, made up of investments from owners and a term loan from Bank of America. The owner investment will be used to cover capital equipment, location, and administrative expenses. These include furniture, equipment, machinery, rent, utility, legal and accounting fees, prepaid insurance, and other expenses. The majority of the term loan will be used to finance opening inventory and advertising expenses, with the rest going towards cash on the balance sheet to ensure liquidity.
ContributorsImam, Ahmed Mohamed (Author) / Ostrom, Amy (Thesis director) / Schlacter, John (Committee member) / Department of Management and Entrepreneurship (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The Confessions of a College Entrepreneur is an honors project with the goal of revealing the business and marketing strategies that Charles Crawford used to create multiple successful companies. It's a collection of personal stories, book notes, millionaire interviews, and experiences that Charles had over the past 4 years of intense business experience and research across multiple industries. Charles wants college students and business owners to succeed in business ventures and life in general. This creative thesis project is the map for how to do just that.
ContributorsCrawford, Charles Joseph (Author) / Budolfson, Arthur (Thesis director) / Giles, Charles (Committee member) / Barrett, The Honors College (Contributor) / Department of Finance (Contributor)
Created2014-12