Nowadays

along with the maturity of the nUV technology

the project that nUV LED excite tricolor phosphor to make white light will be more noticeable.For the lack of phosphors matching the nUV LED chip

it is important significantly to explore this kind of phosphor.So

a new-style red phosphor excited by nUV LED is discussed in this paper.Since the band-gap of CdO(2.3 eV) is smaller than that of ZnO(3.3 eV)

the band-gap of the material with Zn

2+

as host can be narrowed by doping Cd

2+

.And by codoping Eu

3+

and Li

+

the red-light phosphor Cd

x

Zn

1-x

O:Eu

3+

Li

+

is produced.Eu

3+

-doped Cd

x

Zn

1-x

O phosphor was prepared by solid-state method at 1100℃ in atmosphere.The effect of Cd

2+

doping on the luminescence and the excitation spectra of this phosphor has been analyzed.The XRD pattern of the sample shows that the phase of the sample is the simple ZnO phase

the doped ions lock-in Zn site or interstitial site.For the ion radius of Cd

2+

(0.097 nm) is larger than that of Zn

2+

(0.074 nm)

when Cd

2+

take place of the lattice of Zn

2+

the lattice parameter is expanded.So the XRD peaks of Cd-doped ZnO shift to small angles compared with that of pure ZnO.The excitation spectra for 609 nm emission of Cd

x

Zn

1-x

O:Eu is measured at room temperature.The addition of the Cd

2+

narrow the band-gap of the system

and by changing the concentration of Cd

2+

the peak of the excitation spectra can be adjusted between

380

nm and 410 nm.The excitation peak at 466 nm belongs to the

7

F

0

-

5

D

2

transition of Eu

3+

ion

and the peak at 533 nm belongs to the

7

F

0

-

5

D

1

transition of Eu

3+

ion.The luminescence of the sample is a broad-band emission at 520 nm

but the emission of Eu

3+

is not detected when the samples were excited by 381

387

398 and 411 nm UV light.The results show that the energy-transfer between the host and Eu

3+

is not available.In order to enhance the energy-transfer between the host and Eu

3+

Li

+

was co-doped as charge compensator.The emission of Eu

3+

is detected in the emission spectra of the sample adulterating Li

+

as charge compensator.The main peak of the emission spectra locates at 609 nm.It belongs to the

7

F

0

-

5

D

2

transition of Eu

3+

.For the ion radius of Li

+

is very small

it's easy to enter into the crystal lattice of the host.The dopant enhances the energy-transfer between the host and Eu

3+

and also enhances the luminescence intensity.The excitation range of the sample from 380 nm to 410 nm covers the emission wavelength of the ultraviolet LED chip.The intensity of emission was enhanced when Li

+

is introduced into the system

and the photolum inescence of the phosphor is red.So this luminance phosphor is a possible kind of red fluorescent powder applying to white LED.