Room temperature chemical synthesis of Cu(OH)2 thin films for supercapacitor application

• Cu(OH)2 is presented as the new supercapacitive material.
• The novel room temperature method used for the synthesis of Cu(OH)2.
• The hydrous, nanograined Cu(OH)2 shows higher specific capacitance of 120 F/g.

Room temperature soft chemical synthesis route is used to grow nanograined copper hydroxide [Cu(OH)2] thin films on glass and stainless steel substrates. The structural, morphological, optical and wettability properties of Cu(OH)2 thin films are studied by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), UV–vis spectrophotometer and water contact angle measurement techniques. The results showed that, room temperature chemical synthesis route allows to form the nanograined and hydrophilic Cu(OH)2 thin films with optical band gap energy of 3.0 eV. The electrochemical properties of Cu(OH)2 thin films are studied in an aqueous 1 M NaOH electrolyte using cyclic voltammetry. The sample exhibited supercapacitive behavior with 120 F/g specific capacitance.