Fe doped TiO2 thin film as electron selective layer for inverted solar cells

•Fe doped and undoped TiO2 thin films fabricated by sol–gel method.•Inverted type solar cells were fabricated with Fe doped TiO2 thin films.•A dramatic increase was observed in the JSC with the 1% Fe doped TiO2 solar cells.•Isc and Voc showed maximum values at 1% Fe2+ concentration.•Solar cell efficiency of 2.78% was obtained at 1% Fe2+ concentration.