Nano Research & Applications

Editorial

Nanoscale science and engineering are providing us with unprecedented understanding and control of matter at the atomic and fundamental scales. Particularly, they have attracted a significant consideration owing to their extraordinary electronic, optical, and magnetic properties that are often different from their bulk counterparts [1-5].

In the last decades, these materials have raised considerable curiosity in both basic research as well as potential industrial applications [6-10]. They have been used or discussed for a wide variety of practical applications, such as magnetic industries, optical devices, electronics, biomedical applications and biotechnology [11-14]. However, one of the most important challenges in the synthesis of nanoscale materials is how to design and prepare the desired structure with desired multifunctionality [15]. As an important family of nanoscale materials, Magnetic Nanoparticles (MNPs) with Core-Shell (CS), or dumbbell, or dimer type of structures have attracted increasing attention because of their unique functionality mainly due to the combination of interesting physical properties in the same nanoentity. Furthermore, quasi one-dimensional nanostructured materials, such as magnetic single nanowires, nanotubes and core-shell nanowires are expanding even more their capabilities.

Core-shell nanomaterials embody a very exciting constitution integrating different materials, properties and functionality into a single unit. These materials have attracted considerable interest for both fundamental science and technological applications e.g., biomedicine (in vitro and in vivo), high density magnetic recording among others [6-10]. However, the major challenge is the accurate control and tunability of both core and shell size and the chemical composition. In addition, there is also a challenging task of preparing nanoparticles and nanowires of two different materials touching each other through a small area. Today, advances in the chemical synthesis of nanoparticles have achieved significant efforts in controlling the size, composition, shape and crystallinity but still the field is in its premature stage [16].

The continuous progress in the characterization techniques as well as the advances in chemical routes allow one to fabricate more and more complex systems, whose physical properties are yet to understand. In fact, the rapid pace of technological development leads to the necessity of producing tunable devices with controlled nanostructures, even though one not fully understands the complex magnetic response of the novel systems. In turn, these systems display a very complex magnetic behavior, which is certainly the result of surface effects, magnetic interactions, and size effects, among others. From the basic viewpoint, each novel system represents a new challenge, further expanding this fascinating field.

References

1. Kim J, Grate JW, Wang P (2006) Nanostructures for enzyme stabilization. ChemEngSci 61: 1017-1026.
2. Nel A, Xia T, Mädler L, Li N (2006) Toxic potential of materials at the nanolevel. Science 311: 622-627.
3. Maceira VS, Correa-Duarte MA (2007) Increasing the Complexity of Magnetic Core/Shell Structured Nanocomposites for Biological Applications. Adv Mater 19: 4131-4144.
4. Guerrero-Martínez A, Pérez-Juste J, Liz-Marzán LM (2010) Recent progress on silica coating of nanoparticles and related nanomaterials. Adv Mater 22: 1182-1195.
5. Schärt W (2010) Current directions in core-shell nanoparticle design. Nanoscale 2: 829-843.
6. Lu AH, Salabas EL, Schüth F (2007) Magnetic nanoparticles: synthesis, protection, functionalization, and application. AngewChemInt Ed Engl 46: 1222-1244.
7. Lee J, Mahendra S, Alvarez PJ (2010) Nanomaterials in the construction industry: a review of their applications and environmental health and safety considerations. ACS Nano 4: 3580-3590.
8. Corchero JL, Villaverde A (2009) Biomedical applications of distally controlled magnetic nanoparticles. Trends Biotechnol 27: 468-476.
9. Inderhees SE, Borchers JA, Green KS, Kim MS, Sun K, et al. (2008) Manipulating the magnetic structure of Co core/CoO shell nanoparticles: implications for controlling the exchange bias. Phys Rev Lett 101: 117202.
10. Tejada J, Zysler RD, Molins E, Chudnovsky EM (2010) Evidence for quantization of mechanical rotation of magnetic nanoparticles. Phys Rev Lett 104: 027202.
11. Chikazumi S, Taketomi S, Ukita M, Mizukami M, Miyajima H, Setogawa M, Kurihara Y (1987) Physics of magnetic fluids. J MagnMagn Mater 65: 245-251.
12. Lee JS, Park K, Kang MI, Park ILW, Kim SW, et al. (2003) ZnOnanomaterials synthesized from thermal evaporation of ball-milled ZnO powders. J Cryst Growth 254: 423-431.
13. Nogués J, Sort J, Langlais V, Skumryev V, Surinach S, et al. (2005) Exchange bias in nanostructures. Phys Rep 422: 65-118.
14. Gupta AK, Gupta M (2005) Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications. Biomaterials 26: 3995-4021.
15. Liu J, Qiao SZ, Hu QH, Lu GQ (2011) Magnetic nanocomposites with mesoporous structures: synthesis and applications. Small 7: 425-443.
16. Rao CNR, Muller A, Cheetham AK (2004) Chemistry of Nanomaterials. Wiley-VCH Weinheim.