An excellent resistive switching memory behaviour based on assembled MoSe 2 nanosphere arrays Shuangsuo Mao a, *, 1 , Hosameldeen Elshekh a, 1 , Mayameen S. Kadhim c , Yudong Xia a , Guoqiang Fu d , Wentao Hou e , Yong Zhao a, b, c , Bai Sun a, b, ** a School of Physical Science and Technology, Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Southwest Jiaotong University, Chengdu, 610031, China b College of Physics and Energy, Fujian Normal University, Fuzhou, 350117, China c Key Laboratory of Magnetic Levitation Technologies and Maglev Trains, Ministry of Education of China, Superconductivity and New Energy R&D Center (SNERDC), Southwest Jiaotong University, Chengdu, Sichuan, 610031, China d Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, China e College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics (NUAA), Yudao Street 29, 210016, Nanjing, China ARTICLE INFO Keywords: Resistive switching MoSe 2 nanosphere Electronic materials Conducting filaments Memory device ABSTRACT Resistive switching devices based on oxides have outstanding properties, making them a promising candidate to replace today's transistor-based computer memories as non-volatile memories, and can even find future appli- cation in neuromorphic computing. In this work, MoSe 2 nanospheres with ~2.0 μm diameter were firstly syn- thesized by hydrothermal method. Further, a resistive switching (RS) device was prepared using as-assembled MoSe 2 nanospheres array acted as functional layer. The device shows excellent RS memory behaviors with sta- ble resistance ratio and high durability. Besides that, the mechanism of RS behavior is explained from the perspective of formation-disruption of conducting filaments (CF) formed by moving of metal ions on the surface of nanospheres by an external electric field. These characteristics give us a new inspiration for the preparation of memristors that is the memory performance of RS can be improved by assembling nanostructured arrays. 1. Introduction With the rapid development of information technology such as cloud services, smart-phones and tablets, there is an emergency needs for excellent performance memory devices with higher density, low power consumption, and shorter access time [1]. However, due to the flash memory and ferroelectric memory device volume shrinkage, it will be faces challenges that these devices performance approached their limits at present [2,3]. Owing to RS memory device have simple structure and fast switching speed, it has been considered as a promising candidates for next-generation nonvolatile memory [4–7]. Recently, the RS behavior has been observed in different solution-processed multi-layer nanometer material, including graphene oxide mixtures and WO x /WS 2 hetero- structure, in which the resistance value of RS memory device can be changed between a high-resistance state (HRS) and a low-resistance state (LRS) under the action of voltage pulse [8,9]. But for the RS memory device, the RS physical mechanism is still under debate [10]. Among many explanations of mechanism, conductive filaments due to redox of metal ions is considered as an important switched mechanism, and it is widely applied and studied to prove its mechanism [11–14]. It has a simple structure that the MoSe 2 is low dimensional, which is stacked by atomic layers (Se–Mo–Se) through van der Waals forces [15–17]. How- ever, it is believed that the MoSe 2 is one of the most promising materials compared with other low-dimensional materials, and its band-gap is 1.7 eV–1.9 eV, which makes it possible for manufacturing low-dimensional semi-conducting electronic devices [18]. Up to now, many works have reported the MoSe 2 RS memory char- acteristics, such as Y. Yan et al. and P. Han et al. have reported RS memory characteristics in single MoSe 2 nanorods and MoSe 2 nano-array which were embedded in TiO 2 matrix, respectively [19,20], G. Zhou et al. * Corresponding author. ** Corresponding author. School of Physical Science and Technology, Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Southwest Jiaotong University, Chengdu, 610031, China. E-mail addresses: mss@my.swjtu.edu.cn (S. Mao), bsun@swjtu.edu.cn (B. Sun). 1 The authors equally contribute to this work. Contents lists available at ScienceDirect Journal of Solid State Chemistry journal homepage: www.elsevier.com/locate/jssc https://doi.org/10.1016/j.jssc.2019.120975 Received 17 July 2019; Received in revised form 4 September 2019; Accepted 20 September 2019 Available online 21 September 2019 0022-4596/© 2019 Elsevier Inc. All rights reserved. Journal of Solid State Chemistry 279 (2019) 120975