High multifunctional performance structural supercapacitor with Polyethylene oxide cement electrolyte and re duced graphene oxide@CuCo2O4 nanowires

Structural supercapacitors can provide load-bearing and energy storage capacities for zero energy buildings. Unfortunately, trade-off between electrical and mechanical performance of cement electrolytes as well as rigid contact of electrolyte/electrode is great challenge. Herein, polyethylene oxide (PEO) is firstly exploited with 5 wt% KOH or LiOTf to fabricate polymer cement electrolytes with various potential windows via hydration synthesis of ordinary Portland cement (OPC). The prepared polymer cement electrolytes with 2 wt% PEO essentially exhibit optimum balance of compressive strength and ionic conductivity. The reduced graphene oxide (rGO)@CuCo2O4 nanowires utilize the excellent capacitance of binary transition metal oxides as well as long term stability of carbon-based material. Subsequently, two structural supercapacitor devices are assembled with the polymer cement electrolytes and rGO@CuCo2O4 nanowires. The device A presents an energy density of 0.2 mWh/cm(2) and areal capacitance of 439.35 mF/cm(2). The device B delivers an energy density of 0.74 mWh/cm(2) and areal capacitance of 407.07 mF/cm(2). Consequently, the energy efficiency of the electrodes in device A and device B can achieve 18.1% and 17.0%, respectively. The rational combination of electrode and PEO cement electrolyte for structural supercapacitor device paves the well balance to the integration of zero energy buildings and electrochemical energy storage. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study successfully assembled two structural supercapacitor devices using polymer cement electrolytes and metal oxide nanowires, achieving high energy density and areal capacitance with good energy efficiency.