Since the mid-1990s, phosphors have played a key role in emerging solid-state white-lighting technologies that are based on combining a III-nitride-based near-UV or blue solid-state light source with downconversion to longer wavelengths. Almost all widely used phosphors comprise a crystalline oxide, nitride, or oxynitride host that is appropriately doped with either Ce3+ or Eu2+. These ions, with [Xe] 4fn5d0 configurations (n = 1 for Ce3+ and 7 for Eu2+) have proximal excited states that are [Xe] 4fn−15d1. Optical excitation into these states and concomitant reemission can be tuned into the appropriate regions of the visible spectrum by the crystal these ions are hosted in. In this article, we review the current needs and key aspects of the conversion process. We describe some currently used families of phosphors and consider why they are suitable for solid-state lighting. Finally, we describe some empirical rules for new and improved host materials.

Highly ordered mesoporous crystalline MoO(2) materials with bicontinuous Ia3d mesostructure were synthesized by using phosphomolybdic acid as a precursor and mesoporous silica KIT-6 as a hard template in a 10% H(2) atmosphere via nanocasting strategy. The prepared mesoporous MoO(2) material shows a typical metallic conductivity with a low resistivity ( approximately 0.01Omega cm at 300 K), which makes it different from all previously reported mesoporous metal oxides materials. Primary test found that mesoporous MoO(2) material exhibits a reversible electrochemical lithium storage capacity as high as 750 mA h g(-1) at C/20 after 30 cycles, rendering it as a promising anode material for lithium ion batteries.

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