Following dip coating procedure, we have fabricated extended photocatalytic surface (40 mm x 25 mm) of TiO2, nitrogen doped TiO2 (N-TiO2), porous TiO2 (porous-TiO2), nitrogen doped porous TiO2 (porous-N-TiO2) materials over glass slides. A red shift was observed giving a bandgap of 2.56 eV for nitrogen doped TiO2. Raman Scattering shows predominant anatase phase in all the samples along with rutile phase. Using di-chloro fluorescein (DCFH) as a fluorescence reporter molecule, we have characterized OH radical generation. Results show a 5.69 x 10(-8) ppm/cm(2)/s of OH radicals are generated in porous-N-TiO2 coated surface compared to 3.69 x 10(-8) ppm/cm(2)/s in TiO2 which confer a 1.54 increase in the utilization of visible light ability to the catalyst. Photocatalytic ability quantified with Methylene Blue degradation gave similar to 1.48 fold increase under visible light exposure for porous-N-TiO2 relative to TiO2 and the same was 1.1 fold for UV-visible light exposure. Further, the best catalytic degradation turn-over of the surface determined to be 4.55 x 10(-7) ppm/cm(2)/s and 1.61 x 10(-7) ppm/cm(2)/s respectively for UV-vis and visible light exposure. Thus a robust and simpler dip coating methodology giving enhanced visible light photocatalytic activity in polymer mediated nitrogen doped TiO2 system has been demonstrated on a large surface area. We conclude that modification of bandgap of TiO2 by nitrogen doping together with polymer mediated porosity has resulted in a strong visible light activity for this material. Since dip coating approach adopted here is cost-effective and amenable to large scale coating processes, it holds potential in the fabrication of large-scale self-cleansing and antimicrobial surfaces for application in medical and diagnostic industries. (C) 2016 Elsevier B.V. All rights reserved.