Andika Pandu Nugroho, Naufal Hanif Hawari, Bagas Prakoso, Andam Deatama Refino, Nursidik Yulianto, Ferry Iskandar, Evvy Kartini, Erwin Peiner, Hutomo Suryo Wasisto, Afriyanti Sumboja
Due to its high theoretical specific capacity, a silicon anode is one of the candidates for realizing high energy density lithium-ion batteries (LIBs). However, problems related to bulk silicon (e.g., low intrinsic conductivity and massive volume expansion) limit the performance of silicon anodes. In this work, to improve the performance of silicon anodes, a vertically aligned n-type silicon nanowire array (n-SiNW) was fabricated using a well-controlled, top-down nano-machining technique by combining photolithography and inductively coupled plasma reactive ion etching (ICP-RIE) at a cryogenic temperature. The array of nanowires ~1 µm in diameter and with the aspect ratio of ~10 was successfully prepared from commercial n-type silicon wafer. The half-cell LIB with free-standing n-SiNW electrode exhibited an initial Coulombic efficiency of 91.1%, which was higher than the battery with a blank n-silicon wafer electrode (i.e., 67.5%). Upon 100 cycles of stability testing at 0.06 mA cm−2, the battery with the n-SiNW electrode retained 85.9% of its 0.50 mAh cm−2 capacity after the pre-lithiation step, whereas its counterpart, the blank n-silicon wafer electrode, only maintained 61.4% of 0.21 mAh cm−2 capacity. Furthermore, 76.7% capacity retention can be obtained at a current density of 0.2 mA cm−2, showing the potential of n-SiNW anodes for high current density applications. This work presents an alternative method for facile, high precision, and high throughput patterning on a wafer-scale to obtain a high aspect ratio n-SiNW, and its application in LIBs. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Material Science and Engineering Research Group, Faculty of Mechanical and Aerospace, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia; National Battery Research Institute, Gedung EduCenter Lt. 2 Unit 22260 BSD City, South Tangerang, 15331, Indonesia; Mekanisasi Perikanan, Politeknik Kelautan dan Perikanan Sorong, Jl. Kapitan Pattimura, Sorong, 98411, Indonesia; Institute of Semiconductor Technology (IHT) and Laboratory for Emerging Nanometrology (LENA), Technische Universität Braunschweig, Hans-Sommer-Straße 66, Braunschweig, 38106, Germany; Engineering Physics Program, Institut Teknologi Sumatera (ITERA), Jl. Terusan Ryacudu, Way Huwi, Lampung Selatan, 35365, Indonesia; Research Center for Physics, National Research and Innovation Agency (BRIN), Jl. Kawasan Puspiptek 441-442, South Tangerang, 15314, Indonesia; Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia; Center for Science and Technology of Advanced Materials, National Nuclear Energy Agency (BATAN), South Tangerang, 15314, Indonesia; PT Nanosense Instrument Indonesia, Umbulharjo, Yogyakarta, 55167, Indonesia