Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process

Carbon nanotubes are hybridized with metal crystals to impart multifunctionality into the nanohybrids (NHs). Simple but effective synthesis techniques are desired to form both zero-valent and oxides of different metal species on carbon nanotube surfaces. Sol-gel technique brings in significant advan...

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Main Authors: Dipesh Das, Indu V. Sabaraya, Tara Sabo-Attwood, Navid B. Saleh
Format: Article
Language:English
Published: MDPI AG 2018-06-01
Series:Nanomaterials
Subjects:
Online Access:http://www.mdpi.com/2079-4991/8/6/403
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author Dipesh Das
Indu V. Sabaraya
Tara Sabo-Attwood
Navid B. Saleh
author_facet Dipesh Das
Indu V. Sabaraya
Tara Sabo-Attwood
Navid B. Saleh
author_sort Dipesh Das
collection DOAJ
description Carbon nanotubes are hybridized with metal crystals to impart multifunctionality into the nanohybrids (NHs). Simple but effective synthesis techniques are desired to form both zero-valent and oxides of different metal species on carbon nanotube surfaces. Sol-gel technique brings in significant advantages and is a viable technique for such synthesis. This study probes the efficacy of sol-gel process and aims to identify underlying mechanisms of crystal formation. Standard electron potential (SEP) is used as a guiding parameter to choose the metal species; i.e., highly negative SEP (e.g., Zn) with oxide crystal tendency, highly positive SEP (e.g., Ag) with zero-valent crystal-tendency, and intermediate range SEP (e.g., Cu) to probe the oxidation tendency in crystal formation are chosen. Transmission electron microscopy and X-ray diffraction are used to evaluate the synthesized NHs. Results indicate that SEP can be a reliable guide for the resulting crystalline phase of a certain metal species, particularly when the magnitude of this parameter is relatively high. However, for intermediate range SEP-metals, mix phase crystals can be expected. For example, Cu will form Cu2O and zero-valent Cu crystals, unless the synthesis is performed in a reducing environment.
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spelling doaj.art-dfa9c69082e34072813bb7f9073b9c2e2022-12-21T19:40:39ZengMDPI AGNanomaterials2079-49912018-06-018640310.3390/nano8060403nano8060403Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel ProcessDipesh Das0Indu V. Sabaraya1Tara Sabo-Attwood2Navid B. Saleh3Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, TX 78712, USADepartment of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, TX 78712, USADepartment of Environment and Global Health, University of Florida, Gainesville, FL 32610, USADepartment of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, TX 78712, USACarbon nanotubes are hybridized with metal crystals to impart multifunctionality into the nanohybrids (NHs). Simple but effective synthesis techniques are desired to form both zero-valent and oxides of different metal species on carbon nanotube surfaces. Sol-gel technique brings in significant advantages and is a viable technique for such synthesis. This study probes the efficacy of sol-gel process and aims to identify underlying mechanisms of crystal formation. Standard electron potential (SEP) is used as a guiding parameter to choose the metal species; i.e., highly negative SEP (e.g., Zn) with oxide crystal tendency, highly positive SEP (e.g., Ag) with zero-valent crystal-tendency, and intermediate range SEP (e.g., Cu) to probe the oxidation tendency in crystal formation are chosen. Transmission electron microscopy and X-ray diffraction are used to evaluate the synthesized NHs. Results indicate that SEP can be a reliable guide for the resulting crystalline phase of a certain metal species, particularly when the magnitude of this parameter is relatively high. However, for intermediate range SEP-metals, mix phase crystals can be expected. For example, Cu will form Cu2O and zero-valent Cu crystals, unless the synthesis is performed in a reducing environment.http://www.mdpi.com/2079-4991/8/6/403nanohybridhybridizationstandard electron potentialcrystal phasereducing agents
spellingShingle Dipesh Das
Indu V. Sabaraya
Tara Sabo-Attwood
Navid B. Saleh
Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process
Nanomaterials
nanohybrid
hybridization
standard electron potential
crystal phase
reducing agents
title Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process
title_full Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process
title_fullStr Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process
title_full_unstemmed Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process
title_short Insights into Metal Oxide and Zero-Valent Metal Nanocrystal Formation on Multiwalled Carbon Nanotube Surfaces during Sol-Gel Process
title_sort insights into metal oxide and zero valent metal nanocrystal formation on multiwalled carbon nanotube surfaces during sol gel process
topic nanohybrid
hybridization
standard electron potential
crystal phase
reducing agents
url http://www.mdpi.com/2079-4991/8/6/403
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AT tarasaboattwood insightsintometaloxideandzerovalentmetalnanocrystalformationonmultiwalledcarbonnanotubesurfacesduringsolgelprocess
AT navidbsaleh insightsintometaloxideandzerovalentmetalnanocrystalformationonmultiwalledcarbonnanotubesurfacesduringsolgelprocess