en Research Paper Research Paper <span style="font-size:11pt"><span style="line-height:115%"><span style="font-family:Calibri,sans-serif"><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">In this research, Lanthanum (La)-doped Strontium Titanate (STO) with the formula of Sr_1-xLa_xT_iO₃ (LSTO; x=0, 0.03, 0.05, and 0.07) powders have been successfully fabricated by co-precipitation route. The impacts of La³⁺on the structural, microstructure, band-gap, and photocatalytic activity for the degradation of organic pollutants, in this case, methylene blue, under UV exposure, were reported in detail. The formation of undoped and La-doped STO samples with cubic perovskite structures was confirmed by X-ray Diffraction (XRD) results. The presence of La doping affected the microstructure morphology by producing LSTO powders with a larger specific surface area. Besides, the UV absorption of the LSTO powders was enhanced due to the narrowed band gap caused by La³⁺ dopants. Accordingly, an improvement in photocatalytic activity applied for the photodegradation of methylene blue solution was exhibited by the LSTO samples.</span></span></span></span></span></span> lanthanum-doped strontium titanate,photocatalyst,photodegradation,methylene blue 69 78 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-5401-1&slc_lang=en&sid=1 Yofentina Iriani yofent_iriani@staff.uns.ac.id 1800319475328460018969 1800319475328460018969 Yes Department of Physics, Faculty of Mathematics and Natural Science, Universitas Sebelas Maret, 57126, Indonesia Novia Puspita fajarnovia6@gmail.com 1800319475328460018970 1800319475328460018970 No Department of Physics, Faculty of Mathematics and Natural Science, Universitas Sebelas Maret, 57126, Indonesia Dianisa Sandi dianisa875@gmail.com 1800319475328460018971 1800319475328460018971 No Department of Physics, Faculty of Mathematics and Natural Science, Universitas Sebelas Maret, 57126, Indonesia Fahru Nurosyid fahrunurosyid@staff.uns.ac.id 1800319475328460018972 1800319475328460018972 No Department of Physics, Faculty of Mathematics and Natural Science, Universitas Sebelas Maret, 57126, Indonesia Risa Suryana rsuryana@staff.uns.ac.id 1800319475328460018973 1800319475328460018973 No Department of Physics, Faculty of Mathematics and Natural Science, Universitas Sebelas Maret, 57126, Indonesia Didier Fasquelle didier.fasquelle@univ-littoral.fr 1800319475328460018974 1800319475328460018974 No Department of Unitede Dynamique et Structure des Materiaux Moleculaires, Universite du Littoral-Cote d’Opale, CS 80699F-62228 Calais, France