화학공학소재연구정보센터
학회 한국재료학회
학술대회 2016년 가을 (11/16 ~ 11/18, 경주 현대호텔)
권호 22권 2호
발표분야 C. 에너지 재료 분과
제목 Shape controlled TiO2 nanocrystals for Na-ion batteries electrodes: the role of morphology on the electrochemical properties
초록 Lithium ion batteries play a predominant role in the market of power. Nowadays, however, the availability of Li2CO3 is restricted to few countries and lithium may become a strategic material in the near future due to increasing cost and geopolitical issues. For this reasons Na-ion batteries (SIBs) are getting increasing attention thanks to the higher availability of raw materials and the possibility to drive down the energetic demand connected to raw materials extraction and processing. However, the development of a sodium ion based battery technology requires the discovery and the investigation of new electrode materials with reversible Na+intercalation reaction. Many efforts have already been made in the design and characterization of both anode and cathode materials for SiBs so far. Anode materials, especially, still represent a challenging topic needy to be investigated. Many solutions have been proposed to overcome the intrinsic limits of negative electrode materials, namely the low practical specific charge and the fast degradation of electrode characteristics and several classes of materials have been taken into account.  
Aim of the present contribution is the description of the morphological, structural, and electrochemical properties of four anatase samples showing different particle size and shape. The samples were prepared by hydrothermal reaction in presence of different capping agents in order to control the particle growth and assembling. Sample surface investigation was also performed in order to develop an optimized protocol to further functionalize the surface and obtain Carbon/TiO2 core/shell particles (see inset of Figure 1). Electrodes obtain by such materials show a reversible electrochemical behavior in the potential range 2.0-0.1 V  with a pseudo-plateau at 0.8 V vs. Na+/Na. The specific capacity is about 150 mAh/g at 50 mA/g and decreases increasing the current density. In particular, 130 (cycles 31/60) and 100 (cycles 61/100) mAh/g are obtained at 100, and 500 mA/g, respectively (Figure 1). The good results are also confirmed by the capacity retention since no capacity degradation was observed after 250 cycles.
저자 Riccardo Ruffo
소속 Univ. of Milano
키워드 sodium ion battery; anatase TiO2; nanocrystal
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