Interstratified hybrids of α-hydroxides of nickel and cobalt as supercapacitor electrode materials

Zwitterionic p-aminobenzoate ion intercalated α-hydroxides of nickel and cobalt exfoliate in water. The hydroxide monolayers of nickel and cobalt could be co-stacked from a mixture of their colloidal dispersions by the addition of excess of nitrate ions resulting in hybrids in which the layers of the two hydroxides were randomly co-stacked. The α-hydroxide hybrids were explored for their potential as supercapacitor electrode materials. The specific capacitance of hybrids vary with [Ni]/[Co] ratio and a maximum capacitance of 990 F g−1 (at a current density of 1 A g−1) with good cycling stability was obtained for the hybrid with [Ni]/[Co] = 4.