Highly crystalline urchin-like structures made of ultra-thin zinc oxide nanowires

Gokarna, Anisha; Parize, Romain; Kadiri, Hind; Nomenyo, Komla; Patriarche, G.; Miska, Patrice; Lerondel, Gilles

doi:10.1039/c4ra06327a

Cited by 39 publications

(24 citation statements)

References 42 publications

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“…For instance, Elias et al [50] prepared µm-sized hollow spheres with a ZnO nano-columns coating using atom layer deposition and electrodeposition, whilst the method by Shen et al [49] used thermos-evaporation of metallic Zn powder at high temperature (~750 • C). Wahab et al [45] fabricated ZnO nano-flowers with blunt tapering via pH-controlled reactions in a solution of zinc acetate dihydrate and sodium hydroxide at 90 • C. Using a similar approach, Gokarna et al [46] synthesised ZnO urchin-like structures with columnar nanoneedles. Hieu et al [47] sputtered zinc onto a polystyrene-sphere array and subsequent oxidation at 500 • C led to columnar ZnO urchins; while the method used by Taheri et al [48] also involved depositing zinc acetate dihydrate precursor followed by calcination at 500 • C. The solution synthesis method we report here is relatively simpler (at RT and applicable to different surfaces as we show below) compared to these previous studies, producing spiky tapered morphology of the urchin needles with a very high density previously unreported.…”

Section: Resultsmentioning

confidence: 99%

“…Several fabrication methods of ZnO nanostructured surfaces have been reported [21][22][23][24][25][26][27][28], such as hydrothermal synthesis, laser ablation, sputtering, thermal decomposition, evaporation induced self-assembly [29,30], and the sol-gel technique. Various ZnO nanostructures that have been reported include one-dimensional (1-D) morphologies such as nanowires [31][32][33], nanofibers [29,30], nanorods [34][35][36][37], micro-dendrites [38,39], and nanotubular structures [40][41][42][43][44], as well as 3-D architectures such as flowers/urchins [45][46][47][48][49][50], tetrapods/jack-like [51,52], and hedgehogs [53]. The 3-D nanostructures with enhanced surface area may be used as substitutes for 1-D nanostructure arrays with enhanced functionalities, but their fabrication requires either sophisticated instrumentation or elevated temperatures (and thus high energy input).…”

Section: Introductionmentioning

confidence: 99%

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Facile Fabrication of Multifunctional ZnO Urchins on Surfaces

Tripathy

Wąsik

Sreedharan

et al. 2018

Colloids and Interfaces

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Functional ZnO nanostructured surfaces are important in a wide range of applications. Here we report the simple fabrication of ZnO surface structures at near room temperature with morphology resembling that of sea urchins, with densely packed, µm-long, tapered nanoneedles radiating from the urchin center. The ZnO urchin structures were successfully formed on several different substrates with high surface density and coverage, including silicon (Si), glass, polydimethylsiloxane (PDMS), and copper (Cu) sheets, as well as Si seeded with ZnO nanocrystals. Time-resolved SEM revealed growth kinetics of the ZnO nanostructures on Si, capturing the emergence of "infant" urchins at the early growth stage and subsequent progressive increases in the urchin nanoneedle length and density, whilst the spiky nanoneedle morphology was retained throughout the growth. ε-Zn(OH) 2 orthorhombic crystals were also observed alongside the urchins. The crystal structures of the nanostructures at different growth times were confirmed by synchrotron X-ray diffraction measurements. On seeded Si substrates, a two-stage growth mechanism was identified, with a primary growth step of vertically aligned ZnO nanoneedle arrays preceding the secondary growth of the urchins atop the nanoneedle array. The antibacterial, anti-reflective, and wetting functionality of the ZnO urchins-with spiky nanoneedles and at high surface density-on Si substrates was demonstrated. First, bacteria colonization was found to be suppressed on the surface after 24 h incubation in gram-negative Escherichia coli (E. coli) culture, in contrast to control substrates (bare Si and Si sputtered with a 20 nm ZnO thin film). Secondly, the ZnO urchin surface, exhibiting superhydrophilic property with a water contact angle ∼ 0 • , could be rendered superhydrophobic with a simple silanization step, characterized by an apparent water contact angle θ of 159 • ± 1.4 • and contact angle hysteresis ∆θ < 7 • . The dynamic superhydrophobicity of the surface was demonstrated by the bouncing-off of a falling 10 µL water droplet, with a contact time of 15.3 milliseconds (ms), captured using a high-speed camera. Thirdly, it was shown that the presence of dense spiky ZnO nanoneedles and urchins on the seeded Si substrate exhibited a reflectance R < 1% over the wavelength range λ = 200-800 nm. The ZnO urchins with a unique morphology fabricated via a simple route at room temperature, and readily implementable on different substrates, may be further exploited for multifunctional surfaces and product formulations.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Facile Fabrication of Multifunctional ZnO Urchins on Surfaces

Tripathy

Wąsik

Sreedharan

et al. 2018

Colloids and Interfaces

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“…Natural nanomaterials are produced in nature either by biological species or through anthropogenic activities. The production of artificial surfaces with exclusive micro and nanoscale templates and properties for technological applications are readily available from natural sources (70,75,76). Synthetic (engineered) nanomaterials are produced by several methods including mechanical grinding, engine exhaust, and smoke, or are synthesized by physical, chemical, biological or hybrid methods [67,70].…”

Section: Classificationmentioning

confidence: 99%

“…Nanomaterials are being explored for applications in different disciplines including physics, medicine, biomedicine, and chemistry to develop miniaturized devices [87][88][89][90][91]. By realizing the extraordinary properties of nanomaterials such as their high surface area, tuning property in optical emission, electrical and magnetic properties, etc., these can be exploited in bioengineering ranging from drug delivery to biosensors [75,[92][93][94]. The intelligent use of such nano-objects led to clearly enhanced performances with increased sensitivities and lowered detection limits of several orders of magnitude.…”

Section: Nanomaterials In Dna Biosensingmentioning

confidence: 99%

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Nanomaterial‐based Sensors for the Study of DNA Interaction with Drugs

2019

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The interaction of drugs with DNA has been searched thoroughly giving rise to an endless number of findings of undoubted importance, such as a prompt alert to harmful substances, ability to explain most of the biological mechanisms, or provision of important clues in targeted development of novel chemotherapeutics. The existence of some drugs that induce oxidative damage is an increasing point of concern as they can cause cellular death, aging, and are closely related to the development of many diseases. Because of a direct correlation between the response, strength/ nature of the interaction and the pharmaceutical action of DNA‐targeted drugs, the electrochemical analysis is based on the signals of DNA before and after the interaction with the DNA‐targeted drug. Nowadays, nanoscale materials are used extensively for offering fascinating characteristics that can be used in designing new strategies for drug‐DNA interaction detection. This work presents a review of nanomaterials (NMs) for the study of drug‐nucleic acid interaction. We summarize types of drug‐DNA interactions, electroanalytical techniques for evidencing these interactions and quantification of drug and/or DNA monitoring.

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