Structural and electrochemical properties of babassu coconut mesocarp-generated activated carbon and few-layer graphene

Autor(es):Mostrar menos -

Ghosh, Anupama ^[1] ; Razzino, Claudia do Amaral ^[2] ; Dasgupta, Archi ^[3] ; Fujisawa, Kazunori ^{[4, 5]} ; Vieira, Lais Helena S. ^[6] ; Subramanian, Shruti ^[7] ; Costa, Rubens S. ^[8] ; Lobo, Anderson O. ^[8] ; Ferreira, Odair P. ^[6] ; Robinson, Joshua ^[7] ; Terrones, Mauricio ^{[7, 4, 5, 3]} ; Terrones, Humberto ^[9] ; Viana, Bartolomeu C. ^{[1, 8]}

Afiliação do(s) autor(es)

^[1] Fed Univ Piaui UFPI, Dept Phys, FisMat Mat Phys Lab, Teresina, PI - Brazil

^[2] Univ Vale Paraiba UNIVAP, Inst Res & Dev IP&D, Sao Jose Dos Campos, SP - Brazil

^[3] Penn State Univ, Dept Chem, University Pk, PA - USA

^[4] Penn State Univ, Dept Phys, 104 Davey Lab, University Pk, PA 16802 - USA

^[5] Penn State Univ, Ctr 2 Dimens & Layered Mat, University Pk, PA 16802 - USA

^[6] Univ Fed Ceara, Dept Phys, LaMFA, Fortaleza, Ceara - Brazil

^[7] Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 - USA

^[8] Fed Univ Piaui UFPI, Mat Sci & Engn Grad Program PPGCM, LIMAV Interdisciplinary Lab Adv Mat, Teresina, PI - Brazil

^[9] Rensselaer Polytech Inst, Dept Phys Appl Phys & Astron, Troy, NY - USA

• Tipo de documento: Artigo Científico
• Fonte: Carbon; v. 145, p. 175-186, APR 2019.
• Citações Web of Science: 5

Resumo

Activated Carbon (AC) with high specific surface area and elevated porosity was synthesized from babassu mesocarp by hydrothermal carbonization, followed by KOH activation-coupled pyrolysis and subjected to heat-treatment at three different temperatures to generate AC-1100, AC-1400 and AC-2200. Raman spectroscopy, X-Ray diffraction (XRD), transmission electron microscopy (TEM) and N-2 adsorption-desorption were used to characterize structurally the synthesized materials and electrochemical studies to evaluate the capacitance properties. The Raman spectra showed sharpening of graphitic bands and decrease in intensities of amorphous bands with the increase of treatment temperature. AC-2200 showed a significant decrease of I-D/I-G due to the crystal growth in ab plane and drastic increase of I-2D/I-G due to graphitic ordering in c direction, further proven by sharpening of characteristic XRD peaks and visualization of few-layer well-formed graphite micro-crystals by TEM. Although gradual heat treatment resulted in an increase in sample crystallinity, the surface area and porosity decreased, leaving AC-2200 practically non-porous. These changes were reflected in their electrochemical properties as AC-1400 showed highest double layer capacitance owing to an optimization between structural ordering and retention of porosity, while the capacitance, as well as the resistance, of AC-2200, decreases dramatically due to loss of pores and increased crystallinity brought in by graphitization. (c) 2019 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 15/26651-3 - Desenvolvimento de imunossensores para a detecção eletroquímica de biomarcadores de Alzheimer
• Beneficiário: Claudia Do Amaral Razzino
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado