{"id":5053,"date":"2016-11-28T12:38:42","date_gmt":"2016-11-28T15:38:42","guid":{"rendered":"http:\/\/sbpmat.org.br\/?p=5053"},"modified":"2016-12-16T17:35:42","modified_gmt":"2016-12-16T20:35:42","slug":"artigo-em-destaque-muita-ciencia-e-uma-dose-de-acaso-para-chegar-a-receita-de-um-nanocomposito-multifuncional","status":"publish","type":"post","link":"https:\/\/www.sbpmat.org.br\/en\/artigo-em-destaque-muita-ciencia-e-uma-dose-de-acaso-para-chegar-a-receita-de-um-nanocomposito-multifuncional\/","title":{"rendered":"Featured paper. A lot of science and some serendipity to discover the recipe for a multifunctional nanocomposite."},"content":{"rendered":"

[Paper:\u00a0One material, multiple functions: graphene\/Ni(OH)2 thin films applied in batteries, electrochromism and sensors<\/em>. Eduardo G. C. Neiva, Marcela M. Oliveira, M\u00e1rcio F. Bergamini, Luiz H. Marcolino Jr & Aldo J. G. Zarbin. Scientific Reports 6, 33806 (2016). doi:10.1038\/srep33806. Link para o artigo: http:\/\/www.nature.com\/articles\/srep33806<\/a>]<\/p>\n

A lot of science and some serendipity to discover the recipe for a multifunctional nanocomposite.<\/strong><\/p>\n

\"boxnickel_en\"<\/a>A recently published paper in the journal Scientific Reports, from the Nature group, reports a study carried out in universities of the state of Paran\u00e1 (Brazil) on a material based on nickel hydroxide Ni(OH)2 \u2013 a composite of great technological interest [See box]. The group of authors developed an innovative method to fabricate a material based on nickel hydroxide graphene and nanoparticles, prepared thin films with this material and demonstrated the efficiency of these films when used as rechargeable battery electrodes, glycerol sensors and electrochromic materials.<\/p>\n

The work was carried out within the doctoral research of Eduardo Guilherme Cividini Neiva, under the guidance of Professor Aldo Jos\u00e9 Gorgatti Zarbin, in the Chemistry Post-Graduation Program of the Federal University of Paran\u00e1 (UFPR). Neiva began his research on nickel nanoparticles during his undergraduate years, guided by Professor Zarbin. In the master’s program, still with Zarbin, he developed a preparation route of nickel metal nanoparticles for electrochemical applications. After completing the master’s program, Neiva and Zarbin set out to continue the research in Neiva\u2019s doctorate, including graphene in the preparation of nickel metal based nanoparticles to obtain nickel and graphene nanocomposites with different properties. \u201cMost of my scientific interests focus on the preparation of materials with carbon nanostructures, such as nanotubes and graphene,\u201d states Professor Zarbin, who is the corresponding author of the article in Scientific Reports.<\/p>\n

They were surprised by the first laboratory results. In the presence of graphene oxide (as a precursor of graphene in the preparation of the material), the process took a different course. At that time, Neiva and Zarbin saw the potential of these particularities: if well understood, they could be controlled and used to prepare nanocomposites, not only of nickel metal, but also of nickel hydroxide, which would open up new application possibilities. \u201cThere is a phrase by Louis Pasteur I like very much, which applies perfectly in this case: \u201cChance favors the prepared mind,\u201d declares Zarbin.<\/p>\n

Based on this, student and advisor created a simple and direct process for the fabrication\u00a0of graphene and nickel hydroxide nanocomposites. In this innovative process, both components are synthesized together in a one-step reaction. Using this technique, Neiva manufactured the nanocomposites. Pure nickel hydroxide samples were also produced in order to compare them with the nanocomposites.<\/p>\n

The samples were studied through a series of techniques: X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), thermogravimetry, field emission scanning electron microscope (FEG-MEV), and also by means of transmission electron microscopy (TEM) images carried out by Professor Marcela Mohallem Oliveira, from the Federal Technological University of Paran\u00e1 (UTFPR). The comparison between the two materials was favorable to the nanocomposite. \u201cGraphene played a key role in the stabilization of particles at the nanometer scale, increasing the chemical and electrochemical stability of the nanoparticles, and increasing the conductivity of the material, which is fundamental for an improvement in the desired applications,\u201d acknowledges Aldo Zarbin.<\/p>\n

<\/a>
Aldo Jos\u00e9 Gorgatti Zarbin (on the left side) and Eduardo Guilherme Cividini Neiva, the main authors of the paper, standing at the FEG-MEV equipment of the Materials Chemistry Group of UFPR.<\/figcaption><\/figure>\n

The next stage consisted of<\/p>\n

processing the nanocomposites and the nanoparticles of pure nickel hydroxide to obtain thin films, a format that allows using them in the desired applications. \u201cThe deposition of materials in the form of films, covering different surfaces, is a great technological challenge, even greater when dealing with multicomponent materials and insoluble, infusible and intractable materials (all characteristics of the material reported in this article)\u201d, explains Zarbin.<\/p>\n

To overcome this challenge, Neiva used a processing route, known as liquid\/liquid interfacial method, developed in 2010 by the research group led by Zarbin, the Materials Chemistry Group<\/a> of UFPR. This route, besides simple and cheap, explains Professor Zarbin, allows depositing complex materials in the form of homogeneous and transparent films on various types of materials, including plastics. \u201cThe route is based on the high energy at the interface of two immiscible liquids (e.g., water and oil), where the material is initially stabilized to minimize this energy, allowing its subsequent transfer to substrates of interest,\u201d he explained.<\/p>\n

With the nanocomposites, Neiva obtained thin transparent films of about 100 to 500 nm in thickness, with nanoparticles of about 5 nm in diameter, distributed homogeneously on the graphene sheets. The pure nickel hydroxide, however, generated films formed by porous spherical nanoparticles of 30 to 80 nm in diameter, distributed heterogeneously, forming agglomerates in some regions.<\/p>\n

In the final phase of the work, the films deposited on glass and indium tin oxide were tested in three applications, in which the nanocomposite performed better than pure nickel hydroxide.\u00a0 As a material for rechargeable alkaline battery electrodes, the nanocomposite exhibited high energy and high power \u2013 two positive points that are not easily found in the same material. The nanocomposite also showed good performance as an electrochemical sensor. In fact, experiments designed by Professors M\u00e1rcio Bergamini and Luiz Marcolino Jr, also from UFPR, showed that the nanocomposite is a sensitive sensor of glycerol (a compound known commercially as glycerin and used in several industries). Finally, the nanocomposite acted as an efficient electrochromic material. With these characteristics, the films of the UFPR group have a chance to leave the laboratory and be part of innovative products. \u201cThis depends on partners who are interested in scaling the method and testing it on real devices,\u201d says Zarbin.<\/p>\n

For now, in addition to scientific articles such as the one published in the journal Scientific Reports, the work generated several patents, both on the deposition method of thin films and on their applications in gas sensors, transparent electrodes, photovoltaic devices and catalysts. \u201cAnd we have now developed a flexible battery, which was only possible thanks to the film deposition technique we developed,\u201d, adds Professor Zarbin.<\/p>\n

The work, which was developed within the macro projects \u201cINCT of carbon nanomaterials\u201d and \u201cNucleus of Excellence in Nanochemistry and Nanomaterials\u201d, received funding from the federal agencies Capes and CNPq, and the Arauc\u00e1ria Foundation, an agency for scientific and technological development of the state of Paran\u00e1.<\/p>\n

\"This<\/a>
This figure, sent by the authors of the paper, summarizes the main contributions of the paper. In the center, a flask with two liquids and the film at the interface represents the method for thin films processing. A diagram of the film is on the left, with the nickel hydroxide nanoparticles on the graphene sheet. To the right, a photograph of the film deposited on a quartz substrate shows the homogeneity and transparency of the film (it is possible to read text below it). And to the right, from top to bottom, the three applications are shown by a discharge curve (battery), of a transmittance variation curve by the applied potential (electrochromism) and an analytical curve showing the linear variation of the intensity of the current as a function of glycerol concentration in the medium (sensor).<\/figcaption><\/figure>\n

 <\/p>","protected":false},"excerpt":{"rendered":"

[Paper:\u00a0One material, multiple functions: graphene\/Ni(OH)2 thin films applied in batteries, electrochromism and sensors. Eduardo G. C. Neiva, Marcela M. Oliveira, M\u00e1rcio F. Bergamini, Luiz H. Marcolino Jr & Aldo J. G. Zarbin. Scientific Reports 6, 33806 (2016). doi:10.1038\/srep33806. Link para o artigo: http:\/\/www.nature.com\/articles\/srep33806] A lot of science and some serendipity to discover the recipe for […]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[1087,1089,105,1094,557,306,191,1088,1091,1095,1092,216,1090,15,309,1093],"_links":{"self":[{"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/posts\/5053"}],"collection":[{"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/comments?post=5053"}],"version-history":[{"count":18,"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/posts\/5053\/revisions"}],"predecessor-version":[{"id":5151,"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/posts\/5053\/revisions\/5151"}],"wp:attachment":[{"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/media?parent=5053"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/categories?post=5053"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sbpmat.org.br\/en\/wp-json\/wp\/v2\/tags?post=5053"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}