Tunable electronic properties of free-standing Fe-doped GaN nanowires as high-capacity anode of lithium-ion batteries

As an electrode in lithium-ion batteries (LIBs), gallium nitride (GaN) suffers from inferior conductivity and unsatisfied capacity performance. Although nanostructure designing and carbon coating strategies have been adopted to address this concern, improved Li+ storage performance remains highly desirable. In this work, Fe doping strategy was adopted in as-prepared GaN via chemical vapor deposition. Fe doping enhanced electrical conductivity and charge-transfer efficiency. Results showed that the covalent doping of Fe into GaN nanowires provided abundant nanochannels and realized efficient ionic transfer and reduced Li diffusion barrier. These Fe covalently doped GaN nanowire arrays exhibited capacities of up to 612.3 mAh g(-1) at 0.1 A g(-1) after 200 cycles and 338.2 mAh g(-1) at 5.0 A g(-1) after 500 cycles. Density functional theory calculations confirmed that the crystal and band structures were tuned to intensively enhance the ionic transfer efficiency and electrical conductivity and enhance the Li+ storage performance. The electron density strategy provided a significant reference for the rational construction of efficient Li+ storage electrode and beyond. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

Automated summary

The Fe doping strategy in GaN improved electrical conductivity and charge-transfer efficiency, providing abundant nanochannels for efficient ionic transfer and reduced Li diffusion barrier. Fe covalently doped GaN nanowires exhibited enhanced Li+ storage performance, demonstrating the potential for efficient Li+ storage electrodes.