**6. Acknowledgment**

This work was supported by Core Research for Evolutional Science and Technology (CREST) "X-ray pinpoint structural measurement project -Development of the spatial- and time-resolved structural study for nano-materials and devices-" and by the Academy of Finland and the Japan Science and Technology Agency through the Strategic Japanese– Finnish Cooperative Program on "Functional materials". The synchrotron radiation

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**12** 

**Synthesis and Luminescence Properties of** 

Global claim for luminescent materials as efficient sources of energy that can supply sustained competence is growing day by day. The phosphors are facing increased challenges including concerns about global rare earth, environmental and recycling issues, and how to quickly bring to market new technological developments in the industry to meet end-user requirements. A number of applications have emerged in recent years that will change the future of the industry and new technologies like micro/nanoscale innovations and specialty phosphors are harnering increased attention. The primary drivers for growth are the expansion of key end-use applications including solid-state lighting and fluorescent lighting. Current research in nanotechnology is focused on new materials, novel

phenomena, new characterization technique and fabrication of micro/nano devices.

Rare-earth doped molybdates are excellent materials of current interest owing to their interesting optical and opto-electronic properties. Scheelite-type crystalline structures, such as metal molybdates, where molybdenum atoms are coordinated tetrahedrally, have recently attracted great attention because of their promising applications in the electrooptical field (Ryu et al., 2005,a; Gong et al., 2006). Recently, molybdates have been extensively studied due to its attractive luminescence behavior and interesting structural properties (Thongtem et al., 2010), which can be used in a number of fields, such as optic fibers (Ryu et al., 2005, b) laser host materials (Wang et al., 2007), luminescence materials (Zhang et al., 2005; Sen & Pramanik, 2001), efficient catalysts (Ishii et al., 1992), scintillation detectors (Marques et al., 2006), and microwave application (Yang et al., 2009). Among all these molybdates, EuMoO4 is an important opto-electrical material based on its red and white LED phosphors (Rosa et al., 2009). Furthermore, the molybdates allow the doping of different rare-earth ions, which can vary its luminescence properties. Due to the rich emission spectral lines extending from ultraviolet to infrared for Eu3+ ions, spectroscopic

**1. Introduction** 

**EuMoO4 Octahedron-Like Microcrystals** 

Jagannathan Thirumalai1, Rathinam Chandramohan2

*2Department of Physics,Sree Sevugan Annamalai College,* 

*3School of Materials Science and Engineering, Nanyang Technical University, Singapore,* 

*1Department of Physics, B.S. Abdur Rahman University, Vandalur,* 

and Viswanthan Saaminathan3

*Chennai, Tamil Nadu,* 

*Devakottai,Tamil Nadu* 

*1,2India 3Singapore* 

