Microwave synthesized strontium bismuth niobate Sr1-xSnxBi1.95La0.05Nb2O9 (SSBLN) materials are investigated for non-Debye conduction and photocatalytic response. Lone electron pair repulsions between doping tin (Sn2+) and layer bismuth (Bi3+) generate optimal lattice strain. Lattice oxygen, that is critical in photocatalytic applications, is observed to fold along a-c plane on introducing tin. SSBLN compositions possess higher porosity with reduced dimensions. Porosity derived capacitive boundaries promote polaronic hopping in SSBLN materials over diffused ionic conduction. The visible spectrum photocatalytic response is better after doping tin in SSBLN compositions. Mesoporous network and electron-hole pair generation play crucial role in augmented photocatalytic behaviour of SSBLN materials. © 2020 Elsevier B.V.