Directly Grown Germanium Nanowires from Stainless Steel: High-performing Anodes for Li-Ion Batteries

Abstract

Germanium (Ge) nanowires were fabricated directly on stainless steel current collectors for Li-ion batteries without any additional catalytic seeds. Substrates of stainless steel are unconventional materials for the direct growth of nanowires for battery applications. Stainless steel substrates were activated for nanowire growth by annealing them in air at a temperature of 450 °C to form a catalytic iron oxide surface layer. Large yields of Ge nanowires were obtained from oxidized stainless steel via a liquidinjection chemical vapor deposition process, with diphenylgermane (DPG) as a Ge precursor. Fabricated Ge nanowires have uniform morphology and are single-crystalline. The capacity retention from a nanowire anode tested at 0.2 C is very stable, highlighted by reversible capacities of ∼1014 and 894 mAh/g after the 50th and 250th cycles, respectively. The large specific capacity values are one of the highest achieved for binder-free Ge nanomaterial-based anode materials. The high specific capacity values, good capacity retention, and voltage stability observed resulted from the excellent adhesion of the nanowires to the stainless steel current collectors, ensuring good electrical contact and electrical conductivity. Achieving such electrochemical performance from Ge nanowires grown via a significantly simplified direct growth process on a functional conductive substrate demonstrates the potential of directly grown Ge nanowires as a high-performing anode material for Li-ion batteries.

One-Step Grown Carbonaceous Germanium Nanowires and Their Application as Highly Efficient Lithium-Ion Battery Anodes

“…The specific capacity also significantly increased for C-Ge nanowires compared to our previously reported CVD-grown Ge and GeSn nanowires without any carbonaceous surroundings. 14 , 63 …”

“… 12 , 13 Hence, the manufacturing of group IV nanowires, including Ge, for use as anode materials in Li-ion batteries has been widely explored. 14 − 16 One of the other significant strategies to inhibit pulverization of Ge (or Si) materials during charging/discharging cycles include carbon encapsulation of Ge nanostructures. 17 , 18 Designing Ge anode materials by combining a carbon-based porous structure (amorphous carbon, graphene, reduced graphene oxide, etc.)…”

Green Synthesis of Self‐Supported Ni−Fe Oxyhydroxide Pagoda‐Shaped Nanocone Arrays for Electrocatalytic Oxygen Evolution Reaction

“…Nowadays, commercial SS, usually consisting of transition metal elements (eg. Fe, Ni, and Cr), has received extensive attention for the electrochemical study owing to its low-cost, good conductivity and chemical stability, [3][4][5][6][7] especially in the field of electrocatalytic OER. Lots of research results have proved that SS could be converted into cheap, efficient, and stable OER electrodes through specific surface treatments, and the main active ingredient is focused on NiÀ Fe (oxy)hydroxide, which is considered as the highly active species for OER under alkaline conditions.…”

A Nanowire Nest Structure Comprising Copper Silicide and Silicon Nanowires for Lithium‐Ion Battery Anodes with High Areal Loading

“…[1,22,28,[58][59][60][61][62][63][64][65][66][67][68][69] Also, the electrochemical performance of binder-free Si on planar substrates is often characterized by a gradual capacity loss over the lifetime of the cell, primarily due to continual loss of active material through delamination. [61,66,67,70] Substitution of planar substrates with 3D substrates can dually improve capacity retention and achievable loading, forming a robust contact with the Si active layer. [30,[71][72][73][74] Pre-synthesis of Cu silicide/oxide templates can exploit the aforementioned electrochemical inactivity of SiCu deposits, behaving as a robust 3D network for high loading Si growth/deposition.…”