Semiconductor water-based inks: Miniaturized NiO pseudocapacitor electrodes by inkjet printing

The formulation, development and optimization of water-based inks of platelet-like nanoparticles are the mainobjective of this work. As-synthesized Ni(OH)2nanoparticles were dispersed and stabilized in aqueous sus-pension by PEI addition. The combination of DEG (cosolvent) with H2O shows the ideal values of surface tensionand viscosity for piezoelectric inkjet printing, which exhibits a homogeneous jettingflow of the nanoplateletssuspension. The printed nanostructure was sintered at low temperature (325 °C) and the electrochemicaloverview of NiO electrode behavior was described. These printable pseudocapacitors tested by a three-electrodecell have showed a competitive specific capacitance, leading 92% and 78% of capacitance retention for 2000cycles at scan rates of 1 and 2 A/g respectively, and a coulombic efficiency of 100%. The initial performance ofthis printed NiO pseudocapacitor can be compared with others prepared by conventional methods. This newfinding is expected to be particularly useful for the designing of micro-pseudocapacitors.The authors thank ECERS for funding this project through the JECSTrust grant under the contract 2017141, and the support to the projects S2018/NMT-4411 (Comunidad de Madrid) and MAT2015-70780-C4-1and MAT2017-87541-R (MINECO/FEDER). J. Yus acknowledges the Comunidad de Madrid for the support from the Youth Employment Initiative, CAMPD17_ICV_002. Z. Gonzalez acknowledges thePostdoctoral Fellowship: IJCI-2016-28538Peer Reviewe