ORIGINAL PAPER Photoelectrochemical water splitting over mesoporous CuPbI 3 films prepared by electrophoretic technique Rabia Naeem 1 • Rosiyah Yahya 1 • Muhammad Adil Mansoor 1 • Mohd Asri Mat Teridi 2 • Mehran Sookhakian 1 • Asad Mumtaz 3 • Muhammad Mazhar 1 Received: 20 May 2016 / Accepted: 21 November 2016 Ó Springer-Verlag Wien 2017 Abstract Copper lead iodide, CuPbI 3 , nano powder has been synthesized by co-precipitation of PbI 2 on aqueous suspension of CuI followed by solid-state chemical reac- tion; its film was fabricated on FTO substrates by electrophoretic deposition technique and tested for photo- electrochemical water splitting using solar light. The synthesized CuPbI 3 nano powder has been characterized by thermogravimetric, differential thermal analysis, differen- tial scanning calorimetry, and X-ray diffraction. The surface morphology and the elemental composition of the electrophoretically deposited film have been characterized by XRD, Raman spectroscopy, X-ray photoelectron spec- troscopy, field emission scanning electron microscope, and energy dispersive X-ray mapping. The direct band gap energy of CuPbI 3 film of average thickness 96 lm has been estimated at 1.82 eV and the film shows a current density of 216 lA/cm 2 at 0.62 V measured in 0.1 M Na 2 SO 4 solution vs. Ag/AgCl/3 M KCl. This study explores the viability of synthesis of a variety of inorganic halide pho- tocatalysts for enhanced stability and improved solar capturing. Graphical abstract Keywords Cuprous lead iodide  Solid solution film  Electrophoresis  Water splitting Introduction Metal halide perovskites have been demonstrated to be a relatively new class of photoactive materials for optoelec- tronic applications [1–4], high-efficiency photovoltaic cells [2], light emitting diodes [3], dye-sensitized solar cells [5–8], lasers [4], and photodetectors [9]. The oxide perovskite and organic/inorganic hybrid perovskite materials have revealed their potential in photoelectrochemical and photovoltaic applications [10–16]. When using optimized synthesis and fabrication procedures, carefully chosen perovskite design exhibits broad absorption spectra in the UV region making them excellent harvesters that demonstrate properties as either n- or p-type semiconductors with close to optimal band gaps for solar energy conversion. These favourable charac- teristics coupled with the feasibility of their fabrication by solution processing and low production costs make them an excellent candidate as optoelectronic materials [17–19]. Recently, developed organic/inorganic metallic halide Electronic supplementary material The online version of this article (doi:10.1007/s00706-016-1880-x) contains supplementary material, which is available to authorized users. & Muhammad Mazhar mazhar42pk@yahoo.com 1 Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia 2 Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia 3 Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak Darul Ridzuan, Malaysia 123 Monatsh Chem DOI 10.1007/s00706-016-1880-x