History of Materials Research: 30 years of LIEC – UFSCar.


The Interdisciplinary Laboratory of Electrochemistry and Ceramics (LIEC) of the Federal University of São Carlos (UFSCar) is completing 30 years of scientific research, development of innovative products and processes, training of scientists and extension activities.

The idea of creating an interdisciplinary laboratory emerged in 1988, from discussions of three research professors, two from UFSCar and the third from UNESP – Araraquara, with education background in chemistry, physics and physical chemistry. These professors were Elson Longo da Silva, Luís Otávio de Sousa Bulhões and José Arana Varela (deceased in 2016). “The idea came about because we had obtained equipment from funding agencies, but there was not enough space in our respective departments to allocate them,” recounted Elson Longo, now professor emeritus of UFSCar, during the commemoration of the anniversary of LIEC, on March 23.

The idea was materialized thanks to a partnership with Companhia Brasileira de Metais e Metalurgia (CBMM) to finance the construction of the building that would house the equipment. The company, Longo said, was interested in the future laboratory developing some products. “Fortunately, we secured their support for the construction of the building at UFSCar,” explained Longo

Soon after, the laboratory began to receive students interested in participating in the research. The first ones, recalls Longo, were Edson Roberto Leite (now professor at UFSCar), Carlos Alberto Paskocimas (currently at UFRN) Ernesto Chaves Pereira (UFSCar) and Maria Aparecida Zaghete (UNESP). “It can be said that over the past 30 years there have been hundreds of students who have completed their studies at LIEC,” said Longo. In addition to students from various UFSCar courses, LIEC has received young people from other institutions in Brazil and abroad for classes, courses and research at all levels of education.

Partnerships with the industrial sector have marked the history of LIEC in the following years. “The various research themes have been developed, and also changing, from theoretical reflections and from contacts with various companies,” declares Longo. “I emphasize that it was not the production of reflexive knowledge of business needs; on the contrary, such needs have given rise to new interpretive models and dialogues with other theories,” he clarifies.

One of the longest-standing industrial partners is Companhia Siderúrgica Nacional (CSN), with which the laboratory continues to work. Initially, LIEC helped the company eliminate the corrosion that the ceramic burner experienced. “The solution to this problem put the team to research and solve problems related to blast furnace, race channel, torpedo car, converter etc.,” Longo recalled.

Another example cited by Longo is the partnership with 3M of Brazil. LIEC collaborated with the company in the implementation of a varistor plant in Ribeirão Preto, some 100 km from São Carlos. “This collaboration allowed us to open another research sub-area, whereby we produced the first tin oxide varistor,” added the professor emeritus.

Parallel to the projects with companies, LIEC carried out, from the beginning, research in structural ceramics based on zirconia oxide stabilized with rare earths and alkaline earth metals. Thus began the collaboration of the laboratory with the theoretical chemist Juan Andrés, professor of the Universitat Jaume I (Spain) – a cooperation that has lasted for 29 years.

As for the extension activities, LIEC also has successful examples, such as the project through which it brought technical knowledge to artistic ceramics artisans from 9 Brazilian states.

In the 21st century, from multidisciplinary laboratory to materials development center

The year 2000 was a turning point in the scientific trajectory of LIEC. The laboratory was approved in the call for FAPESP CEPID projects, and denominated as Multidisciplinary Center for the Development of Ceramic Materials (CMDMC), and with the guarantee of continuous financing for 11 years. Consequently, the area of diffusion of knowledge was created, international collaborations multiplied (covering more than a dozen countries), and support was given to creating spin-off companies. From this environment came Nanox, specialized in bactericidal nanoparticles, and CosmoScience, dedicated to the characterization of cosmetics.

“This is when LIEC initiated comprehensive modifications in the research of ceramic semiconductors using the Pechini method,” Longo said. “There has been significant expansion in the research on piezoelectric materials, sensors, nanometric particles and thin films for non-volatile memory applications,” affirmed LIEC’s founder.

In 2013, LIEC was again contemplated with the FAPESP CEPID project, now denominated the Center for the Development of Functional Materials (CDMF). In this phase, which continues to this day, the diffusion of knowledge has grown remarkably through the use of social networks and the creation of videos, educational games and radio and television programs. In addition, LIEC researchers have established two spinoffs, NChemi Nanomaterials, of nanomaterials, and Katléia, which specializes in capillary diagnostics. In the scientific research activities, the laboratory has concentrated efforts in obtaining semiconductor nanoparticles with controlled reaction kinetics and morphology.

During the event of the 23rd, Professor Longo thanked everyone who built and still builds the history of LIEC, as well as UFSCar and the funding agencies CAPES, CNPq, FAPESP and FINEP. Finally, Longo addressed a few words to the new generations of researchers who will continue the work. The emeritus professor recommended that they plant new seeds for other crops, and that they create their own models and reinvent themselves.

The emeritus professor’s speech ended with this message: “In these moments of moral and ethical crisis that our country experiences, allied to a silent project of dismantling research and public education at all levels, it is imperative that we gather energies for many present and future confrontations”.

In the first line, from the left, LIEC professors. In the other lines, staff and students of the lab. Photo taken in 2004, at the Chemistry Department of UFSCar.
In the first line, from the left, some LIEC professors. In the other lines, staff and students of the lab. Photo taken in 2004, at the Chemistry Department of UFSCar.

Featured paper: New ozone sensor based on nanorods of silver tungstate.


The scientific paper by members of the Brazilian community on Materials research featured this month is:

Luís F. da Silva, Ariadne C. Catto, Waldir Avansi, Laécio S. Cavalcante, Juan Andrés,  Khalifa Aguir, Valmor R. Mastelaro and Elson Longo. A novel ozone gas sensor based on one-dimensional (1D) α-Ag2WO4 nanostructures. Nanoscale (Print), 2014, v. 1, p. 1-2. DOI: 10.1039/C3NR05837A

New ozone sensor based on nanorods of silver tungstate

A study carried out by a research group from Brazil, with collaboration from French and Spanish scientists, has reported, for the first time, gas detection properties in nanorods of silver tungstate in its alpha phase (α-Ag2WO4).The study showed that this material can be applied as a resistive sensor, displaying great performance when detecting ozone (O3). The work was and coordinated by Elson Longo, Professor at the São Paulo State University “Júlio de Mesquita Filho” (UNESP).

Resistive gas sensors are basically built from a material capable of changing its electrical properties when molecules of a certain gas are adsorbed in its surface. In the specific case of the silver tungstate, when it is submitted to an oxidant gas such as ozone, there is an increase in its electrical resistance that is proportional to the presence and concentration of the gas.

SEM image of the nanorods inside a diagram showing the sensor performance.

In this work, the Brazilian scientists synthesized nanorods of silver tungstate and assembled a sensor based on such nanoparticles. They had put the sensor in a temperature controlled test chamber, exposed it to different concentrations of ozone gas, from 80 to 930 parts per billion (ppb), and evaluated its capacity to detect the ozone.

Present in high atmospheric layers, the ozone plays an important role protecting living beings by absorbing the solar ultraviolet radiation. The ozone is also used by people in several applications, such as, for example, cleaning water. However, the exposition to the gas in certain concentrations may lead to health issues as headache, burning and irritation in the eyes, and respiratory system problems. The World Health Organization (WHO) recommends avoiding the exposure to ozone gas above 120 ppb.

“Subjecting the compound to low amounts of ozone, we observed a fast response, as well as a very short recovering time, making its properties comparable or even better than traditional sensors as tin dioxide (SnO2), tungsten trioxide (WO3), and indium oxide (In2O3),” says Luís Fernando da Silva, first author of the article and postdoctoral fellow of the São Paulo Research Foundation (Fapesp) at UNESP’s Chemistry Institute of Araraquara.

The results were published online in the peer reviewed journal Nanoscale in the end of January this year.

Background of the paper 

The studies with silver tungstate started in the postdoctoral research of Laécio Cavalcante, currently a Professor at Piauí State University (UESPI). Cavalcante synthesized nanorods of silver tungstate using microwave-assisted hydrothermal technique (process that was also used in the synthesis of nanorods from the paper published by Nanoscale). Performing electronic microscopic analysis with the microscope of the Chemistry Institute of Araraquara, the group of scientists coordinated by Professor Longo noticed that the interaction of the electron beam with the material was stimulating the growth of metallic silver particles on the surface of the nanorods. The result of this paper led to an article published in April last year by Scientific Reports (DOI: 10.1038/srep01676).

“Since then, Professor Elson Longo has researched and encouraged the investigation of the potentiality of the α-Ag2WO4 compound”, comments Luís Fernando da Silva. Longo, his team and partners have already observed that the material holds bactericidal (J. Phys. Chem. A, 2014; Doi:10.1021/jp410564p), photoluminescent (J. Phys. Chem. C, 2014, DOI: 10.1021/jp408167v), and photocatalytic properties, with a series of possible applications.

“Based on these potential applications”, Luís Fernando da Silva adds, “I, Professor Waltir Avansi Junior from the Physics Department of the Federal University of São Carlos (UFSCar), jointly with Professor Valmor Mastelaro from the São Carlos Physics Institute of São Paulo University (USP) and his PhD student, Ariadne Catto, started investigating about the detection properties of the non-irradiated α-Ag2WO4 compound (without nanoparticles of metallic silver)”. During the experiments, Silva says, the team noticed that the material was sensitive to detect ethanol and acetone steam and, ultimately, ozone gas, even in low amounts. Assisted by Professors Khalifa Aguir from Université Aix-Marseille (Marseille, France), and Juan Andrés, from Universitat Jaume I (Castelló, Spain), they prepared the communication published by Nanoscale, a renowned journal in the nanotechnology field.

The studies concerning silver tungstate performed by the team of Professor Longo might not end there. According to Luís Fernando da Silva, the team will assess the capacities of the material to detect other gases. In addition to that, returning to the silver tungstate nanorods with nanoparticles of metallic silver, the scientists are going to study the effects of electron irradiation on the gas detection capacity of the material.

“This paper contributes to the discovering of new materials applied as gas sensors”, states the postdoctoral fellow. “However, complementary examinations are necessary in order to achieve a deeper comprehension of the mechanisms involved in the detection, adsorption and desorption processes of the gas(es)”, he concludes.

Minientrevistas com palestrantes do XII Encontro da SBPMat: Elson Longo da Silva (Unesp).


O professor Elson Longo. Crédito: divulgação.

Elson Longo é professor da pós-graduação na Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp) e Professor Emérito da Universidade Federal de São Carlos (UFSCar). Coordena o Centro Multidisciplinar para o Desenvolvimento de Materiais Cerâmicos (CMDMC) e o Instituto Nacional de Ciência e Tecnologia dos Materiais em Nanotecnologia (INCTMN).

Químico formado pela Unesp em 1969, com mestrado e doutorado em Físico-Química pela Universidade de São Paulo (USP), Longo conta com mais de 780 artigos publicados em revistas internacionais, que totalizam mais de 11.180 citações. O professor já foi orientador de mais de 50 mestres e mais de 60 doutores enquanto professor da UFSCar (1989-2005) e da Unesp (a partir de 2005).

Da sua carreira como pesquisador da área de Materiais, Longo destaca uma série de contribuições realizadas nos últimos vinte anos: varistores a base de óxido de zinco, óxido de estanho e titanato de cálcio e cobre; sensores; materiais fotoluminescentes a base de titanatos e tungstato; filmes finos ferroelétricos para utilização em memórias, e materiais fotodegradadores (materiais semicondutores). Também na área de Materiais, Longo participou, junto a empresas da indústria de refratários e siderúrgica, do desenvolvimento de novos tipos de refratários, pisos e azulejos e de cerâmica artística.

É membro titular da Academia Brasileira de Ciências, empossado neste ano, membro da Academia de Ciências do Estado de São Paulo e membro da Academia Internacional de Cerâmica (World Academy of Ceramics).

Atualmente é membro do Conselho da SBPMat. Foi presidente da sociedade de 2004 a 2005.

No XII Encontro da SBPMat, Longo será honrado com a Palestra Memorial “Joaquim Costa Ribeiro”, na qual falará sobre a evolução da pesquisa em Materiais no Brasil.

Segue uma breve entrevista com o palestrante.

Boletim da SBPMat (B.SBPMat): – O senhor tem vasta experiência em projetos realizados junto a empresas. O que teria a comentar sobre a relação da área de Materiais e a indústria no Brasil nesses 40 anos de Engenharia de Materiais? A inserção de engenheiros de Materiais na indústria tem ajudado a melhorar a qualidade, variedade e valor agregado dos produtos brasileiros?

Elson Longo(E.L.): – A área de Materiais evoluiu sobremaneira após a fundação e consolidação da primeira turma de Engenharia de Materiais da UFSCar. Este curso criou no país novas perspectivas para a indústria de um modo geral, pois contemplava três áreas extremamente carentes de especialistas: cerâmica, polímeros e compósitos. Na área de metais já existiam os engenheiros especializados formados em diferentes universidades do país. Vamos tomar somente dois exemplos: a indústria de refratários prosperou e tornou-se competitiva internacionalmente, o mesmo ocorrendo para a indústria de polímeros. Os produtos brasileiros são competitivos no mercado nacional e internacional em função do trabalho dos engenheiros de Materiais e demais categorias de engenharia que trabalham em consonância.

B.SBPMat: – Na sua visão, quais os principais resultados da evolução da formação de recursos humanos na área de Materiais nesses 40 anos no Brasil?

E.L.: – Mais importante que a formação de recursos humanos foi a estruturação de cursos de Engenharia de Materiais em nível de graduação e pós-graduação. Estes cursos hoje estão homogeneamente distribuídos pelo país beneficiando sobremaneira a nossa indústria.

B.SBPMat: – Como você consegue manter uma produtividade científica tão alta e com tantas citações?

E.L.: – A nossa produtividade é fruto de um trabalho em equipe que envolve pesquisadores de São Paulo, Rio Grande do Sul, Paraná, Rio de Janeiro, Minas Gerais, Goiás, Brasília, Sergipe, Paraíba, Rio Grande do Norte, Piauí, Maranhão e Pará. Devo destacar também as interações internacionais que proporcionam grandes oportunidades ao grupo de mostrar o nosso trabalho para a comunidade internacional.

B.SBPMat: – Enquanto participante ativo da história da SBPMat, o que você destacaria dos onze anos de existência da sociedade?

E.L.: – O principal ponto da SBPMat é a harmonia que existe entre os pesquisadores de todos os níveis e a saudável troca de informação entre os mesmos. Por outro lado, a SBPMat desde sua origem tem uma forte participação dos pesquisadores do exterior, o que a coloca na vanguarda do conhecimento.

Informações sobre a palestra de Elson Longo no XII Encontro da SBPMat
Título: “Evolução da pesquisa em Materiais no Brasil”
Resumo: Desde a fundação do curso de Ciência dos Materiais na UFSCar, São Carlos (SP), o país vem evoluindo de modo constante nesta área de conhecimento. É importante ressaltar que esse curso catalisou pesquisadores de Engenharia, Química e Física para o desenvolvimento de materiais cerâmicos, poliméricos e compósitos. Por outro lado, houve também uma ampliação dos cursos de Materiais a nível de graduação e pós graduação, o que contribuiu enormemente para o desenvolvimento da área. Com essa nova estrutura, houve a necessidade da criação da Sociedade Brasileira de Materiais, que vem evoluindo de modo positivo ao longo dos últimos 10 anos.
Quando: 29 de setembro (domingo) das 20h00 às 21h00, após a abertura do evento e antes do coquetel.

XII Encontro da SBPMat: evolução da pesquisa em Materiais no Brasil será tema da palestra memorial.


No Convention Center de Campos do Jordão, logo após a cerimônia de abertura do XII Encontro da SBPMat e antes do coquetel, os participantes do evento poderão assistir à terceira edição da palestra memorial “Joaquim Costa Ribeiro”, na qual o professor Elson Longo falará sobre a evolução da pesquisa em Materiais no Brasil.

Sobre a palestra

Quando: 29 de setembro (domingo), das 20h00 às 21h00.

Título: “Evolução da pesquisa em Materiais no Brasil”

Resumo: Desde a fundação do curso de Ciência dos Materiais na UFSCar, São Carlos (SP), o país vem evoluindo de modo constante nesta área de conhecimento. É importante ressaltar que esse curso catalisou pesquisadores de Engenharia, Química e Física para o desenvolvimento de materiais cerâmicos, poliméricos e compósitos. Por outro lado, houve também uma ampliação dos cursos de Materiais a nível de graduação e pós graduação, o que contribuiu enormemente para o desenvolvimento da área. Com essa nova estrutura, houve a necessidade da criação da Sociedade Brasileira de Materiais, que vem evoluindo de modo positivo ao longo dos últimos 10 anos.

 

XII Encontro da SBPMat: “Memorial Lecture Joaquim Costa Ribeiro” honrará Elson Longo.


Elson Longo da Silva: o próximo homenageado com a palestra memorial da SBPMat.

Desde 2011, a SBPMat outorga, anualmente, uma distinção a um pesquisador de carreira destacada na área de Materiais, quem profere uma palestra durante o encontro anual da sociedade. O nome desse ato é “Memorial Lecture Joaquim Costa Ribeiro”, em homenagem a esse pioneiro da pesquisa experimental em Materiais no Brasil.

Neste ano, o pesquisador honrado será o professor Elson Longo, que ministrará sua palestra na abertura do evento, no dia 29 de setembro, no Convention Center de Campos do Jordão (SP). O professor Longo foi um dos fundadores da SBPMat e um de seus primeiros presidentes.

A honraria já foi outorgada, em anos anteriores, aos professores Sergio Machado Rezende e Sergio Mascarenhas Oliveira.