2012 ©
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Journal Publication
Title of Article Influence of calcination temperature on the structural, morphological, optical, magnetic and electrochemical properties of Cu2P2O7 nanocrystals 
Date of Acceptance 14 September 2018 
Journal
     Title of Journal Journal of Sol-Gel Science and Technology 
     Standard SCOPUS 
     Institute of Journal Spinger US 
     ISBN/ISSN doi.org/10.1007/s10971-018-4819-3 
     Volume 2018 
     Issue 88 
     Month November
     Year of Publication 2018 
     Page 407–421 
     Abstract NH4CuPO4·H2O (NCPO) powder was synthesized by the hydrothermal method. Cu2P2O7 nanocrystals (CPO NCs) were obtained by calcination of the NCPO powders at 550 (CPO5), 600 (CPO6), 700 (CPO7), and 800 (CPO8) °C in argon atmosphere for 3 h. X-ray diffraction (XRD) results indicated a monoclinic structure of NCPO with space group P21/n, while that of CPO NCs was a monoclinic phase with space group C2/c. Moreover, CuHPO4·H2O phase with space group P21/a was found in the product calcined at 550 °C. The estimated crystallite sizes of CPO NCs obtained by XRD (DSh) and Williamson–Hall method (DWh) were found to increase with increasing calcination temperature, ranging from 20 to 43 nm. Micrographs of all CPO NCs obtained by scanning electron microscope showed irregularly large particles of flake-like shape, agglomerated and stacked over each other with micrometer size, ranging from 0.146 to 0.406 μm. X-ray absorption near-edge spectroscopy and X-ray photoelectron spectroscopy results revealed the presence of Cu+ and Cu2+ cations in CPO NCs. The determined optical band gaps of CPO NCs using ultraviolet–visible spectrophotometer were found to increase from 3.761 to 3.802 eV with the increase in calcination temperature. Magnetization measurements of CPO NCs at room temperature using vibrating sample magnetometer revealed a weak ferromagnetic behavior with the enhancement of unsaturated magnetization (M) at 10 kOe from 0.268 to 0.467 emu g−1, coercive field (Hc) from 215.99 to 362.21 Oe, and remanent magnetization (Mr) from 0.0097 to 0.0163 emu g−1, suggesting to originate from the superexchange interaction. The cyclic voltammetry and galvanostatic charge–discharge results of all CPO NC electrodes showed pseudocapacitor behavior associated with Faradaic redox reactions. Increasing calcination temperature could result in the decrease of both specific capacitance (Csc) and capacitance retention values. The highest Csc of 297.521 F g−1 at 1 A g−1 with a good cycling stability after 1000 cycle test of 94.04% was achieved in CPO5 NC electrodes. 
     Keyword Cu2P2O7 nanocrystals Calcination temperature Structure and morphology Optical–magnetic and electrochemical properties Hydrothermal method 
Author
587020048-2 Mr. ATTAPHOL KARAPHUN [Main Author]
Science Doctoral Degree

Reviewing Status มีผู้ประเมินอิสระ 
Status ตีพิมพ์แล้ว 
Level of Publication นานาชาติ 
citation true 
Part of thesis true 
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