Nasicon-type phosphates as electrode materials for safe and efficient electrochemical energy storage M. Amou a,b , B. Larhrib b , M. Srout a,c,⇑ , I. Saadoune a,b a IMED-Lab., Cadi Ayyad University UCA, BP 549, Avenue A. Khattabi, Marrakech, Morocco b Mohammed VI Polytechnic University UM6P, Lot 660-Hay Moulay Rachid, Ben Guerir, Morocco c Department of Chemistry, University of Fribourg Chemin du Musee 9, 1700 Fribourg, Switzerland article info Article history: Received 15 June 2020 Accepted 30 August 2020 Available online xxxx Keywords: Lithium-ion batteries Energy storage Electrode materials NASICON Fast C-rate abstract Nowadays, our lives have become completely dependent on energy. That is the reason why special atten- tion was focused to the development of clean sustainable energy sources due to the depletion of fossil fuel and its negative impact on the environment. In this regard, many electrochemical storage systems were explored. However, lithium ion batteries are the most effective systems dominating the battery market and used in several applications like cellphones, laptops, digital cameras, etc. The performance of such electrochemical energy storage system strongly depends on the used electrode material. Here we will present our recently obtained results on phosphates as safe and cost-efficient electrode materials for the battery technology. Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of The International Confer- ence on Water Depollution and Green Energy 2019. 1. Introduction Since their first commercialization in 1990, lithium-ion batter- ies (LIBs) have been widely used as power sources for a wide range of applications such as mobile phones, laptops, electric/hybrid vehicles, and large-scale systems for renewable energy storage [1]. In recent years, enormous efforts have been made to develop the next generation LIBs and improving the properties of the exist- ing batteries in terms of cost, safety, power and lifetime. Electrode materials are one of the main components influencing these prop- erties [2,3]. Regarding the anode, different type of materials have been investigated including carbonaceous materials, oxides, and phosphates in order to improve the electrochemical performance, cost and mainly the safety of the commercialized Li-ion batteries [4–7]. NASCION-type phosphates with the general formula A x - MM’(PO 4 ) 3 (where M, M’ are transitional metals such as Ti, etc. and A is monovalent or divalent ion such as Li + ) are considered as one of the promising electrode materials for LIBs. Thanks to their attractive structural and thermal stabilities, together with their high ionic conductivity [8,9]. Accordingly, Ni 0.5 Ti 2 (PO 4 ) 3 /C material has been prepared and tested as electrode material for LIBs. 2. Methodology Herein, we have successfully synthesized Ni 0.5 Ti 2 (PO 4 ) 3 NASICON-type material using the conventional sol–gel method, then, carbon coated its particles using sucrose as carbon source. The prepared materials underwent through several structural, morphological, and electrochemical tests in two different potential windows 1.85–3.0 V and 0.5–3.0 V using a diversity of techniques including X-ray Diffraction (SEM), Scanning electron microscopy (SEM), and electrochemical testing (Galvanostatic cycling, cyclic voltammetry). 3. Results and discussion 3.1. Structure and morphology Fig. 1 shows the obtained XRD pattern of the prepared Ni 0.5 Ti 2 (- PO 4 ) 3 material. The recorded data confirmed the obtaining of a rhombohedral (NASICON-type) crystal structure (R-3 space group) as a major phase. Traces of impurity phases such as TiP 2 O 7 and Ni 0.5 TiOPO 4 were also identified but with very small (ignored) intensities. In this rhombohedral system, the structure is built up from lantern-like units in sequence along the c-axis where each unit is https://doi.org/10.1016/j.matpr.2020.08.753 2214-7853/Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of The International Conference on Water Depollution and Green Energy 2019. ⇑ Corresponding author. E-mail addresses: mohammed.srout@unifr.ch, srout.mohammed@gmail.com (M. Srout). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: M. Amou, B. Larhrib, M. Srout et al., Nasicon-type phosphates as electrode materials for safe and efficient electrochemical energy storage, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2020.08.753