Publications by authors named "Jiadeng Zhu"

10 Publications

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Graphene reinforced carbon fibers.

Sci Adv 2020 Apr 24;6(17):eaaz4191. Epub 2020 Apr 24.

Department of Mechanical and Aerospace Engineering, University of Virginia, 122 Engineer's Way, Charlottesville, VA 22904, USA.

The superlative strength-to-weight ratio of carbon fibers (CFs) can substantially reduce vehicle weight and improve energy efficiency. However, most CFs are derived from costly polyacrylonitrile (PAN), which limits their widespread adoption in the automotive industry. Extensive efforts to produce CFs from low cost, alternative precursor materials have failed to yield a commercially viable product. Here, we revisit PAN to study its conversion chemistry and microstructure evolution, which might provide clues for the design of low-cost CFs. We demonstrate that a small amount of graphene can minimize porosity/defects and reinforce PAN-based CFs. Our experimental results show that 0.075 weight % graphene-reinforced PAN/graphene composite CFs exhibits 225% increase in strength and 184% enhancement in Young's modulus compared to PAN CFs. Atomistic ReaxFF and large-scale molecular dynamics simulations jointly elucidate the ability of graphene to modify the microstructure by promoting favorable edge chemistry and polymer chain alignment.
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http://dx.doi.org/10.1126/sciadv.aaz4191DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7182419PMC
April 2020

Unveiling Carbon Ring Structure Formation Mechanisms in Polyacrylonitrile-Derived Carbon Fibers.

ACS Appl Mater Interfaces 2019 Nov 1;11(45):42288-42297. Epub 2019 Nov 1.

Department of Mechanical and Aerospace Engineering , University of Virginia , 122 Engineer's Way , Charlottesville , Virginia 22904 , United States.

As the demand for electric vehicles (EVs) and autonomous vehicles (AVs) rapidly grows, lower-cost, lighter, and stronger carbon fibers (CFs) are urgently needed to respond to consumers' call for greater EV traveling range and stronger safety structures for AVs. Converting polymeric precursors to CFs requires a complex set of thermochemical processes; a systematic understanding of each parameter in fiber conversion is still, to a large extent, lacking. Here, we demonstrate the effect of carbonization temperature on carbon ring structure formation by combining atomistic/microscale simulations and experimental validation. Experimental testing, as predicted by simulations, exhibited that the strength and ductility of PAN CFs decreased, whereas the Young's modulus increased with increasing carbonization temperature. Our simulations unveiled that high carbonization temperature accelerated the kinetics of graphitic phase nucleation and growth, leading to the decrease in strength and ductility but increase in modulus. The methodology presented herein using combined atomistic/microscale simulations and experimental validation lays a firm foundation for further innovation in CF manufacturing and low-cost alternative precursor development.
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http://dx.doi.org/10.1021/acsami.9b15833DOI Listing
November 2019

BODIPY-embedded electrospun materials in antimicrobial photodynamic inactivation.

Photochem Photobiol Sci 2019 Aug 31;18(8):1923-1932. Epub 2019 May 31.

Department of Chemistry, United States Air Force Academy, CO 80840, USA.

Drug-resistant pathogens, particularly those that result in hospital acquired infections (HAIs), have emerged as a critical priority for the World Health Organization. To address the need for self-disinfecting materials to counter the threat posed by the transmission of these pathogens from surfaces to new hosts, here we investigated if a cationic BODIPY photosensitizer, embedded via electrospinning into nylon and polyacrylonitrile (PAN) nanofibers, was capable of inactivating both bacteria and viruses via antimicrobial photodynamic inactivation (aPDI). Materials characterization, including fiber morphology and the degree of photosensitizer loading, was assessed by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and demonstrated that the materials were comprised of nanofibers (125-215 nm avg. diameter) that were thermostable to >300 °C. The antimicrobial potencies of the resultant Nylon-BODIPY and PAN-BODIPY nanofiber materials were evaluated against four strains of bacteria recognized by the World Health Organization as either critical or high priority pathogens: Gram-positive strains methicillin-resistant S. aureus (MRSA; ATCC BAA-44) and vancomycin-resistant E. faecium (VRE; ATCC BAA-2320), and Gram-negative strains multidrug-resistant A. baumannii (MDRAB; ATCC BAA-1605) and NDM-1 positive K. pneumoniae (KP; ATCC BAA-2146). Our results demonstrated the detection limit (99.9999%; 6 log units reduction in CFU mL) photodynamic inactivation of three strains upon illumination (30-60 min; 40-65 ± 5 mW cm; 400-700 nm): MRSA, VRE, and MDRAB, but only minimal inactivation (47-75%) of KP. Antiviral studies employing PAN-BODIPY against vesicular stomatitis virus (VSV), a model enveloped virus, revealed complete inactivation. Taken together, the results demonstrate the potential for electrospun BODIPY-embedded nanofiber materials as the basis for pathogen-specific anti-infective materials, even at low photosensitizer loadings.
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http://dx.doi.org/10.1039/c9pp00103dDOI Listing
August 2019

Carbon-enhanced centrifugally-spun SnSb/carbon microfiber composite as advanced anode material for sodium-ion battery.

J Colloid Interface Sci 2019 Feb 30;536:655-663. Epub 2018 Oct 30.

Fiber and Polymer Science Program, Department of Textile Engineering, Chemistry and Science, College of Textiles, North Carolina State University, Raleigh, NC 27695-8301, USA. Electronic address:

Antimony tin (SnSb) based materials have become increasingly attractive as a potential anode material for sodium-ion batteries (SIBs) owing to their prominent merit of high capacity. However, cyclic stability and rate capability of SnSb anodes are currently hindered by their large volume change during repeated cycling, which results in severe capacity fading. Herein, we introduce carbon-coated centrifugally-spun [email protected] microfiber (CMF) composites as high-performance anodes for SIBs that can maintain their structural stability during repeated charge-discharge cycles. The centrifugal spinning method was performed to fabricate [email protected] due to its high speed, low cost, and large-scale fabrication features. More importantly, extra carbon coating by chemical vapor deposition (CVD) has been demonstrated as an effective method to improve the capacity retention and Coulombic efficiency of the [email protected] anode. Electrochemical test results indicated that the as-prepared [email protected]@C anode could deliver a large reversible capacity of 798 mA h∙g at the 20th cycle as well as a high capacity retention of 86.8% and excellent Coulombic efficiency of 98.1% at the 100th cycle. It is, therefore, demonstrated that [email protected]@C composite is a promising anode material candidate for future high-performance SIBs.
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http://dx.doi.org/10.1016/j.jcis.2018.10.101DOI Listing
February 2019

Reduced Graphene Oxide-Incorporated [email protected] Composites as Anodes for High-Performance Sodium-Ion Batteries.

ACS Appl Mater Interfaces 2018 Mar 9;10(11):9696-9703. Epub 2018 Mar 9.

Fiber and Polymer Science Program, Department of Textile Engineering, Chemistry and Science , North Carolina State University , Raleigh , North Carolina 27695-8301 , United States.

Sodium-ion batteries (SIBs) are promising alternatives to lithium-ion batteries because of the low cost and natural abundance of sodium resources. Nevertheless, low energy density and poor cycling stability of current SIBs unfavorably hinder their practical implementation for the smart power grid and stationary storage applications. Antimony tin (SnSb) is one of the most promising anode materials for next-generation SIBs attributing to its high capacity, high abundance, and low toxicity. However, the practical application of SnSb anodes in SIBs is currently restricted because of their large volume changes during cycling, which result in serious pulverization and loss of electrical contact between the active material and the carbon conductor. Herein, we apply reduced graphene oxide (rGO)-incorporated [email protected] nanofiber ([email protected]@CNF) composite anodes in SIBs that can sustain their structural stability during prolonged charge-discharge cycles. Electrochemical performance results shed light on that the combination of rGO, CNF, and SnSb alloy led to a high-capacity anode (capacity of 490 mAh g  at the 10th cycle) with a high capacity retention of 87.2% and a large Coulombic efficiency of 97.9% at the 200th cycle. This work demonstrates that the [email protected]@CNF composite is a potential and attractive anode material for next-generation, high-energy SIBs.
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http://dx.doi.org/10.1021/acsami.7b18921DOI Listing
March 2018

Biomass-derived porous carbon modified glass fiber separator as polysulfide reservoir for Li-S batteries.

J Colloid Interface Sci 2018 Mar 7;513:231-239. Epub 2017 Nov 7.

Department of Textile Engineering, Chemistry and Science, North Carolina State University, Raleigh, NC 27695-8301, USA. Electronic address:

Biomass-derived porous carbon has been considered as a promising sulfur host material for lithium-sulfur batteries because of its high conductive nature and large porosity. The present study explored biomass-derived porous carbon as polysulfide reservoir to modify the surface of glass fiber (GF) separator. Two different carbons were prepared from Oak Tree fruit shells by carbonization with and without KOH activation. The KOH activated porous carbon (AC) provides a much higher surface area (796 m g) than pyrolized carbon (PC) (334 m g). The R factor value, calculated from the X-ray diffraction pattern, revealed that the activated porous carbon contains more single-layer sheets with a lower degree of graphitization. Raman spectra also confirmed the presence of sp-hybridized carbon in the activated carbon structure. The COH functional group was identified through X-ray photoelectron spectroscopy for the polysulfide capture. Simple and straightforward coating of biomass-derived porous carbon onto the GF separator led to an improved electrochemical performance in Li-S cells. The Li-S cell assembled with porous carbon modified GF separator (ACGF) demonstrated an initial capacity of 1324 mAh g at 0.2 C, which was 875 mAh g for uncoated GF separator (calculated based on the 2nd cycle). Charge transfer resistance (R) values further confirmed the high ionic conductivity nature of porous carbon modified separators. Overall, the biomass-derived activated porous carbon can be considered as a promising alternative material for the polysulfide inhibition in Li-S batteries.
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http://dx.doi.org/10.1016/j.jcis.2017.11.016DOI Listing
March 2018

Poly(vinyl Alcohol) Borate Gel Polymer Electrolytes Prepared by Electrodeposition and Their Application in Electrochemical Supercapacitors.

ACS Appl Mater Interfaces 2016 Feb 29;8(5):3473-81. Epub 2016 Jan 29.

Fiber and Polymer Science Program, Department of Textile Engineering, Chemistry and Science, North Carolina State University , Raleigh, North Carolina 27695-8301, United States.

Gel polymer electrolytes (GPEs) have been studied for preparing flexible and compact electrochemical energy storage devices. However, the preparation and use of GPEs are complex, and most GPEs prepared through traditional methods do not have good wettability with the electrodes, which retard them from achieving their performance potential. In this study, these problems are addressed by conceiving and implementing a simple, but effective, method of electrodepositing poly(vinyl alcohol) potassium borate (PVAPB) GPEs directly onto the surfaces of active carbon electrodes for electrochemical supercapacitors. PVAPB GPEs serve as both the electrolyte and the separator in the assembled supercapacitors, and their scale and shape are determined solely by the geometry of the electrodes. PVAPB GPEs have good bonding to the active electrode materials, leading to excellent and stable electrochemical performance of the supercapacitors. The electrochemical performance of PVAPB GPEs and supercapacitors can be manipulated simply by adjusting the concentration of KCl salt used during the electrodeposition process. With a 0.9 M KCl concentration, the as-prepared supercapacitors deliver a specific capacitance of 65.9 F g(-1) at a current density of 0.1 A g(-1) and retain more than 95% capacitance after 2000 charge/discharge cycles at a current density of 1 A g(-1). These supercapacitors also exhibit intelligent high voltage self-protection function due to the electrolysis-induced cross-linking effect of PVAPB GPEs.
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http://dx.doi.org/10.1021/acsami.5b11984DOI Listing
February 2016

Photosensitizer-Embedded Polyacrylonitrile Nanofibers as Antimicrobial Non-Woven Textile.

Nanomaterials (Basel) 2016 Apr 20;6(4). Epub 2016 Apr 20.

Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA.

Toward the objective of developing platform technologies for anti-infective materials based upon photodynamic inactivation, we employed electrospinning to prepare a non-woven textile comprised of polyacrylonitrile nanofibers embedded with a porphyrin-based cationic photosensitizer; termed PAN-Por. Photosensitizer loading was determined to be 34.8 nmol/mg material; with thermostability to 300 °C. Antibacterial efficacy was evaluated against four bacteria belonging to the ESKAPE family of pathogens (; vancomycin-resistant ; ; and ), as well as . Our results demonstrated broad photodynamic inactivation of all bacterial strains studied upon illumination (30 min; 65 ± 5 mW/cm²; 400-700 nm) by a minimum of 99.9996+% (5.8 log units) regardless of taxonomic classification. PAN-Por also inactivated human adenovirus-5 (~99.8% reduction in PFU/mL) and vesicular stomatitis virus (>7 log units reduction in PFU/mL). When compared to cellulose-based materials employing this same photosensitizer; the higher levels of photodynamic inactivation achieved here with PAN-Por are likely due to the combined effects of higher photosensitizer loading and a greater surface area imparted by the use of nanofibers. These results demonstrate the potential of photosensitizer-embedded polyacrylonitrile nanofibers to serve as scalable scaffolds for anti-infective or self-sterilizing materials against both bacteria and viruses when employing a photodynamic inactivation mode of action.
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http://dx.doi.org/10.3390/nano6040077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5302559PMC
April 2016

NiCu Alloy Nanoparticle-Loaded Carbon Nanofibers for Phenolic Biosensor Applications.

Sensors (Basel) 2015 Nov 20;15(11):29419-33. Epub 2015 Nov 20.

Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China.

NiCu alloy nanoparticle-loaded carbon nanofibers (NiCuCNFs) were fabricated by a combination of electrospinning and carbonization methods. A series of characterizations, including SEM, TEM and XRD, were employed to study the NiCuCNFs. The as-prepared NiCuCNFs were then mixed with laccase (Lac) and Nafion to form a novel biosensor. NiCuCNFs successfully achieved the direct electron transfer of Lac. Cyclic voltammetry and linear sweep voltammetry were used to study the electrochemical properties of the biosensor. The finally prepared biosensor showed favorable electrocatalytic effects toward hydroquinone. The detection limit was 90 nM (S/N = 3), the sensitivity was 1.5 µA µM(-1), the detection linear range was 4 × 10(-7)-2.37 × 10(-6) M. In addition, this biosensor exhibited satisfactory repeatability, reproducibility, anti-interference properties and stability. Besides, the sensor achieved the detection of hydroquinone in lake water.
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http://dx.doi.org/10.3390/s151129419DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4701341PMC
November 2015

Sulfur gradient-distributed CNF composite: a self-inhibiting cathode for binder-free lithium-sulfur batteries.

Chem Commun (Camb) 2014 Sep;50(71):10277-80

Department of Textile Engineering, Chemistry and Science, North Carolina State University, Raleigh, NC 27695, USA.

A self-inhibiting, gradient sulfur structure was designed and developed by the synthesis of a carbon nanofiber-sulphur composite via sulfur vapor deposition method for use as a binder-free sulfur cathode, exhibiting high sulfur loading (2.6 mg cm(-2)) and high sulfur content (65%) with a stable capacity of >700 mA h g(-1).
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http://dx.doi.org/10.1039/c4cc04970eDOI Listing
September 2014