Contents lists available at ScienceDirect Journal of Luminescence journal homepage: www.elsevier.com/locate/jlumin Cerium and manganese doped alumina matrices: Preparation, characterization and kinetic analysis of their glow curves Jorge Rojas a , Rafael Cogollo a , Miriam Gil b , Jorge Usma b , Omar Gutiérrez b,* , Adriana Soto b a Grupo de Materiales y Física Aplicada, Facultad de Ciencias Básicas, Universidad de Córdoba, Carrera 6A #77-305, Montería, Colombia b Grupo Alquimia, Facultad Ciencias Exactas y Aplicadas, Instituto Tecnológico Metropolitano, Calle 73 No 76A-354 Vía al Volador, Medellín, Colombia ARTICLEINFO Keywords: Alumina Cerium-doped alumina Manganese-doped alumina Codoping Thermoluminescent matrices with doping agents ABSTRACT This paper reports the preparation, characterization and thermoluminescent (TL) response of two types of alumina matrices: pure and doped with both cerium and manganese. We can observe that the peptization technique, followed by drying and calcination processes, allowed to obtain fne micrometrical powders to build compact pills without using any additive during pressing. The results show that the pure alumina matrix has fve TL traps that appear to be six when cerium contents are low (0.1wt%). Furthermore, the sensibility of the alumina matrix is greater with these cerium contents. Additionally, a scheme of electronic traps in Al 2 O 3 :Ce matrices was proposed by using deconvolution with logistic asymmetric functions. The kinetic parameters for every electronic trap were calculated by applying Rasheedy’s method. Nevertheless, manganese-doped and co- doped alumina matrices did not show thermoluminescent activity. 1. Introduction One of the materials that can be produced as micro-sized particles andplayanimportantroleinseveralapplicationsisalumina,whichcan be confrmed in reports about the improvement of mechanical prop- erties when micro alumina particles are present in diferent amounts in these kinds of materials [1]. In this regard, Al 2 O 3 -based ceramics with enhanced properties should be obtained to produce micro-sized parti- cles without agglomerates. For that reason, ceramic micro-sized parti- cles have been obtained by several routes such as sol-gel [2], hydro- thermal synthesis [3], co-precipitation [4], combustion synthesis [5] and, recently, microencapsulation by emulsion [6]. Advances in synthesis methods have enabled to enhance the properties of alumina, and its greater sensibility and stability at room temperature has ex- panded the scope of its applications, such as thermoluminescence [7]. Diferent alumina phases are important for industrial applications; one particular case is the boehmite phase, which is considered the main precursor for alumina powders [8]. Adding agents that promote den- sifcation processes in amorphous and crystalline matrices could modify the physicochemical properties of alumina [9–11]; particularly, the thermoluminescent (TL) behavior because a synergic efect is produced by electronic oxygen vacancies in Al 2 O 3 structures when doping agents are added [12–19]. Previous studies have shown that these systems can be used as TL sensors for dosimetry because they are sensible to radiations and ex- hibit good resistance to chemical attacks and thermal stress [20,21]. In this kind of sensors, the knowledge of TL curves is essential to study dosimetry properties [22,23], because it must be possible to correlate doseswithkineticfactors(orderandactivationenergy)inordertoexert a greater control over the TL process when dosimetry devices are built. Consequently, the aim of this work is to propose a chemical synthesis route in order to obtain alumina in boehmite phase as a precursor for aluminum matrices doped with cerium and manganese and evaluate their thermoluminescence response. The material was characterized by particle size distribution, XRD, Infrared spectroscopy FTIR,TG,andDSC.TheTLresponsewillbeevaluatedbydeconvolution technique in order to produce an in-depth description and under- standing of the electronic phenomena of the TL activity. 2. Materials and methods 2.1. Synthesis of pure, cerium-doped and manganese-doped Al 2 O 3 matrices Aluminum hydroxide particles (reagent grade, Sigma-Aldrich), Al (OH) 3 , were treated with a peptization technique [24]. Hydrochloric acid (37%, Sigma-Aldrich) was added (0.1mol HCl/1mol Al(OH) 3 ratio) under refux conditions (48hat 100°C) in order to activate and promote the formation of aluminum oxo-hydroxide, AlOOH formation. https://doi.org/10.1016/j.jlumin.2019.116572 Received 21 February 2019; Received in revised form 18 May 2019; Accepted 23 June 2019 * Corresponding author. E-mail address: omargutierrez@itm.edu.co (O. Gutiérrez). Journal of Luminescence 214 (2019) 116572 Available online 24 June 2019 0022-2313/ © 2019 Elsevier B.V. All rights reserved. T