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Kalluri A, Dharmadhikari B, Debnath D, Patra P, Kumar CV. Advances in Structural Modifications and Properties of Graphene Quantum Dots for Biomedical Applications. ACS Omega 2023; 8:21358-21376. [PMID: 37360447 PMCID: PMC10286289 DOI: 10.1021/acsomega.2c08183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Accepted: 05/19/2023] [Indexed: 06/28/2023]
Abstract
Graphene quantum dots (GQDs) are carbon-based, zero-dimensional nanomaterials and unique due to their astonishing optical, electronic, chemical, and biological properties. Chemical, photochemical, and biochemical properties of GQDs are intensely being explored for bioimaging, biosensing, and drug delivery. The synthesis of GQDs by top-down and bottom-up approaches, their chemical functionalization, bandgap engineering, and biomedical applications are reviewed here. Current challenges and future perspectives of GQDs are also presented.
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Affiliation(s)
- Ankarao Kalluri
- Department
of Material Science, Department of Chemistry, and Department of Molecular and Cell
Biology, University of Connecticut, Storrs, Connecticut 06269, USA
| | - Bhushan Dharmadhikari
- Department
of Electrical and Computer Engineering and Technology, Minnesota State University, Mankato, Minnesota 56001, USA
| | - Debika Debnath
- Department of Biomedical Engineering and Department of
Mechanical Engineering, University of Bridgeport, Bridgeport, Connecticut 06604, USA
| | - Prabir Patra
- Department of Biomedical Engineering and Department of
Mechanical Engineering, University of Bridgeport, Bridgeport, Connecticut 06604, USA
| | - Challa Vijaya Kumar
- Department
of Material Science, Department of Chemistry, and Department of Molecular and Cell
Biology, University of Connecticut, Storrs, Connecticut 06269, USA
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2
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Malhotra M, Kalluri A, Kumar CV. Nanoarmored Multi-Enzyme Cascade Catalysis. Methods Mol Biol 2022; 2487:205-225. [PMID: 35687239 DOI: 10.1007/978-1-0716-2269-8_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This chapter reports a single-step preparation of nanoarmored bi-enzyme systems assembled on 1-D and 2-D nanomaterials, with glucose oxidase and peroxidase enzymes as model systems for cascade bio-catalysis. This is a simple and facile method to both exfoliate the bulk 1D (carbon nanotubes, CNT) and 2D nanomaterials (α-Zirconium phosphate, α-ZrP) and bind the enzymes in a single step. Exfoliation of the bulk material enhances the accessible surface area of the materials for the enzyme binding, and it also boosts the diffusion of reagents from the bulk phase to the active sites of the bio-catalysts. For example, a mixture of horseradish peroxidase, glucose oxidase, and bovine serum albumin (BSA) were adsorbed on the surfaces of the α-ZrP nanoplates or carbon nanotubes (CNT) as the bulk materials are exfoliated simultaneously, in a one-step process. The resulting bio-catalysts were thoroughly characterized by powder X-ray diffraction, electron microscopy, biochemical and biophysical methods, while enzyme activity studies proved successful binding of enzymes with retention of activities or even enhancements in their specific activities. For example, GOx/HRP/BSA/CNT displayed 6 times the activity of a mixture of GOx/HRP/BSA, under otherwise identical conditions. Similarly, GOx/HRP/BSA/ZrP had 3.5 times the activity of the corresponding mixture of GOx/HRP/BSA, in the absence of the nanoplates. These robust nano-dispersions worked extraordinarily well as active bio-catalysts. These two kinds of fabricated biocatalyst dispersions are also highly stable.
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Affiliation(s)
- Mansi Malhotra
- Department of Chemistry, University of Connecticut, Storrs, CT, USA
| | - Ankarao Kalluri
- Department of Material Science, University of Connecticut, Storrs, CT, USA
| | - Challa Vijaya Kumar
- Department of Chemistry, University of Connecticut, Storrs, CT, USA.
- Department of Material Science, University of Connecticut, Storrs, CT, USA.
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA.
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Yang T, Benson K, Fu H, Xue T, Song Z, Duan H, Xia H, Kalluri A, He J, Cheng J, Kumar CV, Lin Y. Modeling and Designing Particle-Regulated Amyloid-like Assembly of Synthetic Polypeptides in Aqueous Solution. Biomacromolecules 2021; 23:196-209. [PMID: 34964619 DOI: 10.1021/acs.biomac.1c01230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In cells, actin and tubulin polymerization is regulated by nucleation factors, which promote the nucleation and subsequent growth of protein filaments in a controlled manner. Mimicking this natural mechanism to control the supramolecular polymerization of macromolecular monomers by artificially created nucleation factors remains a largely unmet challenge. Biological nucleation factors act as molecular scaffolds to boost the local concentrations of protein monomers and facilitate the required conformational changes to accelerate the nucleation and subsequent polymerization. An accelerated assembly of synthetic poly(l-glutamic acid) into amyloid fibrils catalyzed by cationic silica nanoparticle clusters (NPCs) as artificial nucleation factors is demonstrated here and modeled as supramolecular polymerization with a surface-induced heterogeneous nucleation pathway. Kinetic studies of fibril growth coupled with mechanistic analysis demonstrate that the artificial nucleators predictably accelerate the supramolecular polymerization process by orders of magnitude (e.g., shortening the assembly time by more than 10 times) when compared to the uncatalyzed reaction, under otherwise identical conditions. Amyloid-like fibrillation was supported by a variety of standard characterization methods. Nucleation followed a Michaelis-Menten-like scheme for the cationic silica NPCs, while the corresponding anionic or neutral nanoparticles had no effect on fibrillation. This approach shows the effectiveness of charge-charge interactions and surface functionalities in facilitating the conformational change of macromolecular monomers and controlling the rates of nucleation for fibril growth. Molecular design approaches like these inspire the development of novel materials via biomimetic supramolecular polymerizations.
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Affiliation(s)
- Tianjian Yang
- Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Kyle Benson
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Hailin Fu
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Tianrui Xue
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Ziyuan Song
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Hanyi Duan
- Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Hongwei Xia
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Ankarao Kalluri
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Jie He
- Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States.,Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Jianjun Cheng
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.,Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Challa V Kumar
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Yao Lin
- Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States.,Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
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Rawat S, Jain KG, Gupta D, Raghav PK, Chaudhuri R, Pinky, Shakeel A, Arora V, Sharma H, Debnath D, Kalluri A, Agrawal AK, Jassal M, Dinda AK, Patra P, Mohanty S. Graphene nanofiber composites for enhanced neuronal differentiation of human mesenchymal stem cells. Nanomedicine (Lond) 2021; 16:1963-1982. [PMID: 34431318 DOI: 10.2217/nnm-2021-0121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To differentiate mesenchymal stem cells into functional dopaminergic neurons using an electrospun polycaprolactone (PCL) and graphene (G) nanocomposite. Methods: A one-step approach was used to electrospin the PCL nanocomposite, with varying G concentrations, followed by evaluating their biocompatibility and neuronal differentiation. Results: PCL with exiguous graphene demonstrated an ideal nanotopography with an unprecedented combination of guidance stimuli and substrate cues, aiding the enhanced differentiation of mesenchymal stem cells into dopaminergic neurons. These newly differentiated neurons were seen to exhibit unique neuronal arborization, enhanced intracellular Ca2+ influx and dopamine secretion. Conclusion: Having cost-effective fabrication and room-temperature storage, the PCL-G nanocomposites could pave the way for enhanced neuronal differentiation, thereby opening a new horizon for an array of applications in neural regenerative medicine.
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Affiliation(s)
- Sonali Rawat
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Krishan Gopal Jain
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Deepika Gupta
- SMITA Research Lab, Department of Textile & Fibre Engineering, Indian Institute of Technology, New Delhi, 110016, India
| | - Pawan Kumar Raghav
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Rituparna Chaudhuri
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Pinky
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Adeeba Shakeel
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Varun Arora
- SMITA Research Lab, Department of Textile & Fibre Engineering, Indian Institute of Technology, New Delhi, 110016, India
| | - Harshita Sharma
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Debika Debnath
- Department of Biomedical Engineering, Department of Mechanical Engineering, University of Bridgeport, Bridgeport, CT 06604, USA
| | - Ankarao Kalluri
- Department of Biomedical Engineering, Department of Mechanical Engineering, University of Bridgeport, Bridgeport, CT 06604, USA
| | - Ashwini K Agrawal
- SMITA Research Lab, Department of Textile & Fibre Engineering, Indian Institute of Technology, New Delhi, 110016, India
| | - Manjeet Jassal
- SMITA Research Lab, Department of Textile & Fibre Engineering, Indian Institute of Technology, New Delhi, 110016, India
| | - Amit K Dinda
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Prabir Patra
- Department of Biomedical Engineering, Department of Mechanical Engineering, University of Bridgeport, Bridgeport, CT 06604, USA
| | - Sujata Mohanty
- Stem Cell Facility, DBT-Centre of Excellence for Stem Cell Research, All India Institute of Medical Sciences, New Delhi, 110029, India
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Jeong S, Pinals RL, Dharmadhikari B, Song H, Kalluri A, Debnath D, Wu Q, Ham MH, Patra P, Landry MP. Graphene Quantum Dot Oxidation Governs Noncovalent Biopolymer Adsorption. Sci Rep 2020; 10:7074. [PMID: 32341425 PMCID: PMC7184744 DOI: 10.1038/s41598-020-63769-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 03/31/2020] [Indexed: 01/06/2023] Open
Abstract
Graphene quantum dots (GQDs) are an allotrope of carbon with a planar surface amenable to functionalization and nanoscale dimensions that confer photoluminescence. Collectively, these properties render GQDs an advantageous platform for nanobiotechnology applications, including optical biosensing and delivery. Towards this end, noncovalent functionalization offers a route to reversibly modify and preserve the pristine GQD substrate, however, a clear paradigm has yet to be realized. Herein, we demonstrate the feasibility of noncovalent polymer adsorption to GQD surfaces, with a specific focus on single-stranded DNA (ssDNA). We study how GQD oxidation level affects the propensity for polymer adsorption by synthesizing and characterizing four types of GQD substrates ranging ~60-fold in oxidation level, then investigating noncovalent polymer association to these substrates. Adsorption of ssDNA quenches intrinsic GQD fluorescence by 31.5% for low-oxidation GQDs and enables aqueous dispersion of otherwise insoluble no-oxidation GQDs. ssDNA-GQD complexation is confirmed by atomic force microscopy, by inducing ssDNA desorption, and with molecular dynamics simulations. ssDNA is determined to adsorb strongly to no-oxidation GQDs, weakly to low-oxidation GQDs, and not at all for heavily oxidized GQDs. Finally, we reveal the generality of the adsorption platform and assess how the GQD system is tunable by modifying polymer sequence and type.
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Affiliation(s)
- Sanghwa Jeong
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Rebecca L Pinals
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Bhushan Dharmadhikari
- Department of Electrical and Computer Engineering & Technology, Minnesota State University, Mankato, MA, 56001, USA
| | - Hayong Song
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea
| | - Ankarao Kalluri
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT, 06604, USA
| | - Debika Debnath
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT, 06604, USA
| | - Qi Wu
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT, 06604, USA
| | - Moon-Ho Ham
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea
| | - Prabir Patra
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT, 06604, USA. .,Department of Mechanical Engineering, University of Bridgeport, Bridgeport, CT, 06604, USA.
| | - Markita P Landry
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA, 94720, USA. .,Innovative Genomics Institute (IGI), Berkeley, CA, 94720, USA. .,California Institute for Quantitative Biosciences, QB3, University of California, Berkeley, Berkeley, CA, 94720, USA. .,Chan-Zuckerberg Biohub, San Francisco, CA, 94158, USA.
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7
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Xing J, Singh S, Zhao Y, Duan Y, Guo H, Hu C, Ma A, George R, Xing JZ, Kalluri A, Macwan I, Patra P, Chen J. Increasing vaccine production using pulsed ultrasound waves. PLoS One 2017; 12:e0187048. [PMID: 29176801 PMCID: PMC5703500 DOI: 10.1371/journal.pone.0187048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 10/12/2017] [Indexed: 01/14/2023] Open
Abstract
Vaccination is a safe and effective approach to prevent deadly diseases. To increase vaccine production, we propose that a mechanical stimulation can enhance protein production. In order to prove this hypothesis, Sf9 insect cells were used to evaluate the increase in the expression of a fusion protein from hepatitis B virus (HBV S1/S2). We discovered that the ultrasound stimulation at a frequency of 1.5 MHz, intensity of 60 mW/cm2, for a duration of 10 minutes per day increased HBV S1/S2 by 27%. We further derived a model for transport through a cell membrane under the effect of ultrasound waves, tested the key assumptions of the model through a molecular dynamics simulation package, NAMD (Nanoscale Molecular Dynamics program) and utilized CHARMM force field in a steered molecular dynamics environment. The results show that ultrasound waves can increase cell permeability, which, in turn, can enhance nutrient / waste exchange thus leading to enhanced vaccine production. This finding is very meaningful in either shortening vaccine production time, or increasing the yield of proteins for use as vaccines.
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Affiliation(s)
- Jida Xing
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
| | - Shrishti Singh
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, Connecticut, United States of America
| | - Yupeng Zhao
- Department of Biomedical Engineering, University of Alberta, Edmonton, Canada
| | - Yan Duan
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, Canada
| | - Huining Guo
- Department of Physiatry, University of Alberta, Edmonton, Canada
| | - Chenxia Hu
- School of Chinese Pharmaceutical Science, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Allan Ma
- Akshaya Bio Inc., Edmonton, Alberta, Canada
| | | | - James Z. Xing
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Canada
| | - Ankarao Kalluri
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, Connecticut, United States of America
| | - Isaac Macwan
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, Connecticut, United States of America
| | - Prabir Patra
- Department of Biomedical Engineering, University of Bridgeport, Bridgeport, Connecticut, United States of America
- Department of Mechanical Engineering, University of Bridgeport, Bridgeport, Connecticut, United States of America
| | - Jie Chen
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
- Department of Biomedical Engineering, University of Alberta, Edmonton, Canada
- * E-mail:
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Kolay A, Kokal RK, Kalluri A, Macwan I, Patra PK, Ghosal P, Deepa M. New Antimony Selenide/Nickel Oxide Photocathode Boosts the Efficiency of Graphene Quantum-Dot Co-Sensitized Solar Cells. ACS Appl Mater Interfaces 2017; 9:34915-34926. [PMID: 28921953 DOI: 10.1021/acsami.7b09754] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A novel assembly of a photocathode and a photoanode is investigated to explore their complementary effects in enhancing the photovoltaic performance of a quantum-dot solar cell (QDSC). While p-type nickel oxide (NiO) has been used previously, antimony selenide (Sb2Se3) has not been used in a QDSC, especially as a component of a counter electrode (CE) architecture that doubles as the photocathode. Here, near-infrared (NIR) light-absorbing Sb2Se3 nanoparticles (NPs) coated over electrodeposited NiO nanofibers on a carbon (C) fabric substrate was employed as the highly efficient photocathode. Quasi-spherical Sb2Se3 NPs, with a band gap of 1.13 eV, upon illumination, release photoexcited electrons in addition to other charge carriers at the CE to further enhance the reduction of the oxidized polysulfide. The p-type conducting behavior of Sb2Se3, coupled with a work function at 4.63 eV, also facilitates electron injection to polysulfide. The effect of graphene quantum dots (GQDs) as co-sensitizers as well as electron conduits is also investigated in which a TiO2/CdS/GQDs photoanode structure in combination with a C-fabric CE delivered a power-conversion efficiency (PCE) of 5.28%, which is a vast improvement over the 4.23% that is obtained by using a TiO2/CdS photoanode (without GQDs) with the same CE. GQDs, due to a superior conductance, impact efficiency more than Sb2Se3 NPs do. The best PCE of a TiO2/CdS/GQDs-nS2-/Sn2--Sb2Se3/NiO/C-fabric cell is 5.96% (0.11 cm2 area), which, when replicated on a smaller area of 0.06 cm2, is seen to increase dramatically to 7.19%. The cell is also tested for 6 h of continuous irradiance. The rationalization for the channelized photogenerated electron movement, which augments the cell performance, is furnished in detail in these studies.
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Affiliation(s)
- Ankita Kolay
- Department of Chemistry, Indian Institute of Technology Hyderabad , Kandi 502285, Sangareddy, Telangana, India
| | - Ramesh K Kokal
- Department of Chemistry, Indian Institute of Technology Hyderabad , Kandi 502285, Sangareddy, Telangana, India
| | | | | | | | - Partha Ghosal
- Defence Metallurgical Research Laboratory, Defence Research and Development Organisation (DRDO) , Hyderabad 500058, Telangana, India
| | - Melepurath Deepa
- Department of Chemistry, Indian Institute of Technology Hyderabad , Kandi 502285, Sangareddy, Telangana, India
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Kokal RK, Deepa M, Kalluri A, Singh S, Macwan I, Patra PK, Gilarde J. Solar cells with PbS quantum dot sensitized TiO 2-multiwalled carbon nanotube composites, sulfide-titania gel and tin sulfide coated C-fabric. Phys Chem Chem Phys 2017; 19:26330-26345. [PMID: 28936513 DOI: 10.1039/c7cp05582j] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Novel approaches to boost quantum dot solar cell (QDSC) efficiencies are in demand. Herein, three strategies are used: (i) a hydrothermally synthesized TiO2-multiwalled carbon nanotube (MWCNT) composite instead of conventional TiO2, (ii) a counter electrode (CE) that has not been applied to QDSCs until now, namely, tin sulfide (SnS) nanoparticles (NPs) coated over a conductive carbon (C)-fabric, and (iii) a quasi-solid-state gel electrolyte composed of S2-, an inert polymer and TiO2 nanoparticles as opposed to a polysulfide solution based hole transport layer. MWCNTs by virtue of their high electrical conductivity and suitably positioned Fermi level (below the conduction bands of TiO2 and PbS) allow fast photogenerated electron injection into the external circuit, and this is confirmed by a higher efficiency of 6.3% achieved for a TiO2-MWCNT/PbS/ZnS based (champion) cell, compared to the corresponding TiO2/PbS/ZnS based cell (4.45%). Nanoscale current map analysis of TiO2 and TiO2-MWCNTs reveals the presence of narrowly spaced highly conducting domains in the latter, which equips it with an average current carrying capability greater by a few orders of magnitude. Electron transport and recombination resistances are lower and higher respectively for the TiO2-MWCNT/PbS/ZnS cell relative to the TiO2/PbS/ZnS cell, thus leading to a high performance cell. The efficacy of SnS/C-fabric as a CE is confirmed from the higher efficiency achieved in cells with this CE compared to the C-fabric based cells. Lower charge transfer and diffusional resistances, slower photovoltage decay, high electrical conductance and lower redox potential impart high catalytic activity to the SnS/C-fabric assembly for sulfide reduction and thus endow the TiO2-MWCNT/PbS/ZnS cell with a high open circuit voltage (0.9 V) and a large short circuit current density (∼20 mA cm-2). This study attempts to unravel how simple strategies can amplify QDSC performances.
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Affiliation(s)
- Ramesh K Kokal
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285, Sangareddy, Telangana, India.
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Gurka G, Kalluri A, McDonald B, Ohman J, Feigelson P, Rosenwasser L. 107 Allergen specific T cell clones can be utilized to map allergenic epitopes for T cell activation. J Allergy Clin Immunol 1988. [DOI: 10.1016/0091-6749(88)90343-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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