Solution mixing preparation of PVDF/ZnO polymeric composite films engineered for heterogeneous photocatalysis Crissie Dossin Zanrosso , 1 Diego Piazza, 2 Marla Azário Lansarin 1 1 Department of Chemical Engineering, Federal University of Rio Grande do Sul, 90035-007, Porto Alegre, RS, Brazil 2 Polymer Laboratory, University of Caxias do Sul, 95070-560, Caxias do Sul, RS, Brazil Correspondence to: C. Dossin Zanrosso (E-mail: crissie@enq.ufrgs.br) ABSTRACT: Despite the efforts of the scientific community, carrying out photocatalyst immobilization so that industrial application of photocatalysis becomes economically feasible is still a challenge to be overcome. In this work, polyvinylidene fluoride (PVDF)/ZnO composites were prepared by solution mixing based on solid knowledge of membrane technology and with the help of a powerful exper- imental design for systematic evaluation of the interaction among variables. A strategy for variable screening was used, followed by a complete evaluation at two levels, leading to predictive models. As a result, photocatalyst amount, pore agent concentration, and wet thickness were the most significant in the target molecule discoloration. With this, it was possible to obtain a 40 and 186% enhancement in photocatalytic efficiency compared to previous results and simple photolysis, respectively. Finally, the samples were characterized by FTIR-ATR, XRD, and SEM and chemical, crystalline and morphological differences were observed both with nanoparticle and pore agent incorporation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48417. KEYWORDS: catalysts; composites; nanoparticles; nanowires and nanocrystals; separation techniques; X-ray Received 14 May 2019; accepted 24 July 2019 DOI: 10.1002/app.48417 INTRODUCTION The photocatalysis process has been shown to be effective in a wide range of industrial applications, such as the environmental remediation of contaminants of emerging concern, 1 the CO 2 reduction for fuels production, 2 the inactivation of bacteria, fungi, and viruses 3 and the organic synthesis of higher added-value products. 4 In the last few decades, many researches have focused on photocatalysis efficiency enhancement through innovative photocatalysts materials (SiO 2 /shell/void/TiO 2 , 5 Zr x Si 1 - x O 2 / shell/void/TiO 2 , 6 bismuth-based semiconductors, 7 and others semiconductors 8 ), new photocatalyst synthesis pathways, 9 process intensification for environmental proposes, 10,11 new application for higher value-added products, 4,12 among other initiatives. 1 In spite of good results obtained so far, which indicates the great potential of this technology, there are still few applications of photocatalysis in real production or environmental remediation processes. 13 Some examples of commercially launched products are Puralytics Lilypad, Puralytics Shield 1000, Purifics PhotoCat, and BrightWater Titanium Advanced Oxidation Process. The interesting fact is that in all those cases, the photocatalyst TiO 2 was immobilized, either directly or indirectly, in or on supports. Therefore, what we know so far is that more efficient materials and process conditions are needed for practical large-scale appli- cation and that the immobilized system seems to be a good solu- tion for photocatalyst reutilization, which could translate into the greatest incentive to promote commercial use. According to Srikanth et al. (2017), 14 it is important that some requirements be fulfilled in order to achieve satisfactory immobilized materials for environmental remediation, such as (1) the immobilization should be permanent so that the particles are not released into the environment; (2) the photocatalyst should present a low decrease in its photocatalytic efficiency upon immobilization; (3) the support material should present resistance against strong oxidative radicals, and (4) the resulted photo- catalytic material should be able interact with the contaminant to be treated. Also, the composite should preferably be easy to handle for practical application into several reactor types and formats. In this context, the polymeric materials have the advantage of a wide range of properties, especially mechanical and chemical ones that could be manipulated for this specific application. Since early publications of photocatalysts immobilization, polymer supports have been presented as a promising alternative. 15,16 Additional Supporting Information may be found in the online version of this article. © 2019 Wiley Periodicals, Inc. 48417 (1 of 12) J. APPL. POLYM. SCI. 2019, DOI: 10.1002/APP.48417