Helinando Pequeno de Oliveira

Universidade Federal do Vale do São Francisco

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Mateus Matiuzzi da Costa

Universidade Federal do Vale do São Francisco

Celso P. de Melo

Universidade Federal de Pernambuco

Fernando Antônio Gomes da Silva

Universidade Federal do Vale do São Francisco

Iuri Custodio Montes Candido

Universidade Federal do Vale do São Francisco

Glaydson S. dos Reis

Universidade Federal do Rio Grande do Sul

Mário César Albuquerque de Oliveira

Universidade Federal do Vale do São Francisco

Evando S. Araújo

Universidade Federal do Vale do São Francisco

Ravi Moreno Araújo Pinheiro Lima

Universidade Federal do Vale do São Francisco

César A.S. Andrade

Universidade Federal de Pernambuco

Ariadne H. P. de Oliveira

Universidade Federal da Bahia

Cooperative Institutions

Universidade Federal do Vale do São Francisco

148

Universidade Federal de Pernambuco

Universidade de São Paulo

Universidade Federal Rural de Pernambuco

Universidade Federal da Bahia

Universidade do Vale do Sapucaí

Universidade São Francisco

Universidade Federal de Minas Gerais

Instituto Federal do Sertão Pernambucano

Universidade Federal de São Carlos

Author Statistics

Papers

Citation

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Synergistic interaction of clove, cinnamon, and eucalyptus essential oils impregnated in cellulose acetate electrospun fibers as antibacterial agents against Staphylococcus aureus

Brazilian Journal of Microbiology (2023)

Jarbas Freitas Amarante Mateus Matiuzzi da Costa Jackson Roberto Guedes da Silva Almeida Helinando Pequeno de Oliveira

Eucalyptus oil

Cellulose acetate

Bacterial Cellulose

10.1007/s42770-023-01048-5

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Citations (2)

All‐gel‐state supercapacitors of polypyrrole reinforced with graphene nanoplatelets

Journal of Applied Polymer Science (2021)

Ravi Moreno Araújo Pinheiro Lima Helinando Pequeno de Oliveira

Abstract The development of supramolecular structures (conducting hydrogels) obtained from the charge–charge interaction of sodium dodecyl sulfate micelles and oppositely charged polypyrrole chains represents an important step to obtain self‐supported and flexible electrodes for supercapacitors. Herein, the energy density of polypyrrole hydrogel‐based supercapacitors is enhanced by the incorporation of graphene nanoplatelets that introduced the electrical double capacitance contribution to the overall response. The electrochemical performance of synthesized electrodes was optimized from the relative variation in the concentration of supramolecular arrangements (micelles of sodium dodecyl sulfate), pyrrole, and graphene nanoplatelets. As result, higher capacitive retention is observed for modified electrodes (with the incorporation of graphene) – in order of 90% after 1000 cycles of use, preserving the high conductivity and intrinsic mechanical properties (flexibility and stretchability) reaching an areal capacitance of 210.7 mFcm −2 .

Polypyrrole

Sodium dodecyl sulfate

10.1002/app.51216

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Citations (17)

Temperature and Frequency Dependence of the Electrical Properties of Thin Organic Films

Molecular Crystals and Liquid Crystals (2002)

Helinando Pequeno de Oliveira Celso P. de Melo

We performed an experimental investigation of the low temperature electrical behavior of thin films of conducting polymers. Using the selfassembly technique, thin samples with a total thickness in the range of 5-60 bilayers were prepared by the alternate deposition of polypyrrole (PPY) and polythiophene acetic acid (PTAA) layers on a glass substrate. The intrinsic anisotropy of the samples was manifested in their electrical characteristics, since the temperature dependence observed for the conductivity along the surface was different from that measured in the direction perpendicular to the substrate. While the longitudinal component of the resistivity tensor changes with temperature as in a typical semiconductor, a "metallic-like" profile is identified for the transversal component, confirming that different transport mechanisms must dominate the charge transfer along these two directions. A preliminary investigation of the dielectric characteristics of those samples has allowed us a better understanding of the charge storage processes in these samples.

Polythiophene

Polypyrrole

Organic semiconductor

Atmospheric temperature range

Thin layers

10.1080/10587250210486

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Citations (0)

Metal nanoparticles/carbon dots nanocomposites for SERS devices: trends and perspectives

SN Applied Sciences (2020)

Elisângela Gomes de Lima Oliveira Helinando Pequeno de Oliveira Anderson S. L. Gomes

Carbon fibers

Noble metal

10.1007/s42452-020-03306-9

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Citations (26)

Electrochemical Synthesis and Characterization of Multi-walled Carbon Nanotubes/Polypyrrole and Polypyrrole Hollow Nanotubes

Fullerenes Nanotubes and Carbon Nanostructures (2013)

Alysson H. P. Oliveira Helinando Pequeno de Oliveira

We report the electrochemical synthesis and characterization of hybrid structures composed by hollow nanotubes of polypyrrole and core-shell composites of multi-walled carbon nanotubes (MWCNTs) coated by polypyrrole (PPy). The synthesis of these systems is critically dependent on relative concentration of carbon nanotubes (introduced as a template for polymerization) and affects the level of conductivity of media, the diameter and relative roughness of synthesized nanotubes. The competition induced by polymerization on the surface of different templates (aggregates of methyl orange and MWCNT) allows that smooth structures can be obtained, minimizing the synthesis of granules of polypyrrole, in a process that affects the morphology, thermal and electrical properties of synthesized materials. As a result, the impedance of mixed composite is lower than the other obtained for each system (MWCNT and hollow nanotubes of PPy), in an indication that synergistic interaction is favored during the synthesis.

Polypyrrole

Methyl orange

10.1080/1536383x.2011.643429

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Citations (2)

Carbon Nanotube@MnO2@Polypyrrole Composites: Chemical Synthesis, Characterization and Application in Supercapacitors

Materials Research (2016)

Ariadne H. P. de Oliveira Márcio Luis Ferreira Nascimento Helinando Pequeno de Oliveira

Core/shell structures of carbon-based materials/ metal oxide have been considered as potential candidates for electrochemical devices due to their improved pseudocapacitance/electrical double layer capacitance and high conductivity/ superior surface area. The development of multiple core-shell structures of MWCNT@MnO2@PPy was analyzed as a standard procedure for mass production of supercapacitor electrodes. The relative concentration of carbon nanotubes in the composite was varied to optimize the double layer capacitance contribution in overall response of device. Resulting structures presented capacitance in order of 272.7 Fg-1 and reasonable cycling performance.

Pseudocapacitance

10.1590/1980-5373-mr-2016-0347

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Citations (31)

Photovoltaic Response of Ultrathin Films of Retinal Derivatives

physica status solidi (b) (2002)

A.C. Tenório Helinando Pequeno de Oliveira Alisson Michel Silva Celso P. de Melo

Langmuir–Blodgett mixed films of retinal derivatives and fatty acids deposited on conducting glass slides were used in the present study of the photovoltaic response of retinal derivatives. The presence of incident light can affect the compression isotherms of the Langmuir films of cis and trans retinal in a distinct manner by changing the intrinsic organization of the floating monolayer, and a definite difference in the photovoltaic response of the corresponding ultrathin films of retinal derivatives is observed.

10.1002/1521-3951(200207)232:1<50::aid-pssb50>3.0.co;2-q

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Citations (6)

Statistics design for the synthesis optimization of lignin-sulfonate sulfur-doped mesoporous carbon materials: promising candidates as adsorbents and supercapacitors materials

Scientific Reports (2024)

Glaydson S. dos Reis Shaikshavali Petnikota Helinando Pequeno de Oliveira Irineu A.S. de Brum Mikael Thyrel

This study employed lignin-sulfonated (LS) to develop biobased carbon materials (LS-Cs) through a sulfur-doping approach to enhance their physicochemical properties, adsorption capabilities, and energy storage potentials. Various characterization techniques, including BET surface area analysis, SEM imaging, XPS, Raman spectroscopy, and elemental composition (CHNS), were employed to assess the quality of the LS-Cs adsorbent and electrode samples. Response Surface Methodology (RSM) was utilized for optimizing the two main properties (specific surface area, A

BET theory

Specific surface area

Carbon fibers

10.1038/s41598-024-75003-1

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Citations (1)

A Short Review on the Electrochemical Performance of Hierarchical and Nitrogen-Doped Activated Biocarbon-Based Electrodes for Supercapacitors

Nanomaterials (2021)

Glaydson S. dos Reis Helinando Pequeno de Oliveira Sylvia H. Larsson Mikael Thyrel Éder C. Lima

Cheap and efficient carbon electrodes (CEs) for energy storage systems (ESS) such as supercapacitors (SCs) and batteries are an increasing priority issue, among other things, due to a globally increasing share of intermittent electricity production (solar and wind) and electrification of transport. The increasing consumption of portable and non-portable electronic devices justifies research that enables environmentally and economically sustainable production (materials, processing techniques, and product design) of products with a high electrochemical performance at an acceptable cost. Among all the currently explored CEs materials, biomass-based activated carbons (AC) present enormous potential due to their availability and low-cost, easy processing methods, physicochemical stability, and methods for self-doping. Nitrogen doping methods in CEs for SCs have been demonstrated to enhance its conductivities, surface wettability, and induced pseudocapacitance effect, thereby delivering improved energy/power densities with versatile properties. Herein, a short review is presented, focusing on the different types of natural carbon sources for preparing CEs towards the fabrication of SCs with high electrochemical performance. The influences of ACs’ pore characteristics (micro and mesoporosity) and nitrogen doping on the overall electrochemical performance (EP) are addressed.

Pseudocapacitance

Carbon fibers

10.3390/nano11020424

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Citations (69)

Humidity-sensing properties of hierarchical TiO2:ZnO composite grown on electrospun fibers

Journal of Materials Science Materials in Electronics (2017)

Evando S. Araújo Juliano Libardi M. Pedro Helinando Pequeno de Oliveira

Electrospinning

10.1007/s10854-017-7571-5

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Citations (18)