Urea treated WO3 and SnO2 as cost effective and efficient counter electrodes of dye sensitized solar cells. - Hytham Elbohy; Khan Mamun Reza; Eman A. Gamal; Salem Abdulkarim; Ashim Gurung; Geetha Varnekar; Muhammad Hassan Sayyad; Qiquan Qiao (EIT, 2016)