Facile hybridization of Ni@Fe2O3 superparticles with functionalized reduced graphene oxide and its application as anode material in lithium-ion batteries.
In our present work we developed a novel graphene wrapping approach of Ni@Fe2O3 superparticles, which can be extended as a concept approach for other nanomaterials as well. It uses sulfonated reduced graphene oxide, but avoids thermal treatments and use of toxic agents like hydrazine for its reduction. The modification of graphene oxide is achieved by the introduction of sulfate groups accompanied with reduction and elimination reactions, due to the treatment with oleum. The successful wrapping of nanoparticles is proven by energy dispersive X-ray spectroscopy, high-resolution transmission electron microscopy and Raman spectroscopy. The developed composite material shows strongly improved performance as anode material in lithium-ion batteries (compared to unwrapped Ni@Fe2O3) as it offers a reversible capacity of 1051mAhg(-1) after 40 cycles at C/20, compared with 460mAhg(-1) for unwrapped Ni@Fe2O3. The C rate capability is also improved by the wrapping approach, as specific capacities for wrapped particles are about twice of those offered by unwrapped particles. Additionally, the benefit for the use of the advanced superparticle morphology is demonstrated by comparing wrapped Ni@Fe2O3 particles with wrapped Fe2O3 nanorice.
Institute of Organic Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
Gregor
G
Backert
Institute of Organic Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany; Present address: Materials Research Laboratory, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
Bernd
B
Oschmann
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
Muhammad Nawaz
MN
Tahir
Helmholtz Institute Ulm (HIU), Electrochemistry I, Helmholtzstr. 11, 89081 Ulm, Germany; Institute of Physical Chemistry, University of Muenster, Corrensstr. 28/30, 48149 Muenster, Germany; Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 Karlsruhe, Germany.
Franziska
F
Mueller
Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
Ingo
I
Lieberwirth
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
Benjamin
B
Balke
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
Wolfgang
W
Tremel
Helmholtz Institute Ulm (HIU), Electrochemistry I, Helmholtzstr. 11, 89081 Ulm, Germany; Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 Karlsruhe, Germany. Electronic address: stefano.passerini@kit.edu.
Stefano
S
Passerini
Institute of Organic Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany. Electronic address: zentel@uni-mainz.de.
Rudolf
R
Zentel
Anode materials; Graphene wrapping; Lithium-ion battery; Superparticles; Surface functionalization