The American Chemical Society journal Nano Letters has published a paper called Porous Amorphous FePO4 Nanoparticles Connected by Single-Wall Carbon Nanotubes for Sodium Ion Battery Cathodes written by scientists from the Departments of Materials Science and Engineering, and Chemical Engineering of the University of Maryland.
Sodium-ion batteries (SIBs), say the authors, are promising candidates for the applications of large-scale energy storage due to their cost-effective and environment-friendly characteristics, but they note that it has remained a practical challenge to find a cathode material for SIBs showing adequate performance in terms of capacity, reversibility, etc.
“We report here,” they write in the paper, “a nanocomposite material of amorphous, porous FePO4 nanoparticles electrically wired by single-wall carbon nanotubes as a potential cathode material for SIBs. The hydrothermally synthesized nanocomposite shows excellent cell performance with unprecedented cycling stability and reversibility. The discharge capacity of as high as 120 mAh/g is delivered at a 0.1 C rate (10 mA/g). The capacity retentions are about 70 mAh/g, 60 mAh/g, and 55 mAh/g at higher currents of 20 mA/g, 40 mA/g, and 60 mA/g, respectively. Even at a 1 C rate (100 mA/g), a capacity of about 50 mAh/g is still retained after 300 cycles.
“With a simple synthetic procedure, cost-effective chemicals, and desirable cell performance, this method offers a highly promising candidate for commercialised cathode materials of SIBs.”
While not one of the Nano Letters paper authors, Sang Bok Lee, another Maryland University researcher and associate professor in the university’s Department of Chemistry and Biochemistry, is investigating the electrochemical properties of nanotube arrays which hold promise in the development of supercapacitors. The University of Maryland is part of the Nanostructures for Electrical Energy Storage (NEES) EFRC, a multi-institutional research centre and one of 46 Energy Frontier Research Centers established by the US Department of Energy in 2009.
