Hydrotalcite-like compounds(HTlcs)

which are formulated as [

M

1-x

2+

M

x

3+

(OH)

2

]

A

n/x

n-

·mH

2

O have received increase interest owing to their particular properties such as infrared absorption.The properties are derived from their special layers structure

which are made of metal cations(

M

2+

and

M

3+

)of similar ionic radii and coordinated by six oxygen atoms forming

M

2+

/

M

3+

(OH)

6

octahedra.Luminescent materials containing rare-earth ions have been special interest for their sharp and intense emission bands based on f→f transitions of rare-earth ions.In fact

europium compounds are the most widely used due to their efficient red-emitting luminescence

so doping of europium ions into HTlcs makes it possible to combine the optical properties of molecular compounds with the mechanical and chemical stability of a solid matrix.Therefore

it suggests that there is a new method of designing dual-functional materials.In order to getting dual-functional materials with red luminescence and selectivity IR adsorption properties

we studied the HTlcs compound containing Eu

3+

ions.The samples of Mg-Al-Eu-hydrotalcite-like compounds(MgAlEuCO

3

-HTlcs)were prepared by co-precipitation and through hydrothermal treatment.Results of XRD showed that the pure MgAlEuCO

3

-HTlcs were obtained from solution of magnesium

aluminium and europium nitrates

n(Mg

2+

):n(Al

3+

)=3

n(Eu

3+

):[n(Al

3+

)+n(Eu

3+

)]=5%～50%

by co-precipitation with a mixture of sodium carbonate and hydroxide at a fixed pH value of 10±0.1

and hydrothermal treating at 100℃ for 8h.The MgAlEuCO

3

-HTlcs crystallinity decreases with increasing Eu

3+

dosage in the synthesis mixture

and the value of d110 of MgAlEuCO

3

-HTlcs is more larger in XRD at one time.Three intense IR bands of FT-IR spectra at 600～900cm

-1

1250～1350cm

-1

and 3420～3480cm

-1

are argument with

M

OH(

M

=Mg

Al

Eu)

CO

3

and OH stretching vibrations

respectively.Under excitation by 399 nm

there are three sharp emissions peaked at 594

620 and 700 nm in emission spectrum of MgAlEuCO

3

-HTlcs

which belong to the

5

D

0

→

7

F

J

(J=1

2

4)transition of Eu

3+

ion.Besides

the intensity of luminescence changed with the increasing of Eu/Al molar ratio.All of results revealed that a few Al

3+

ions in layers of HTlcs were replaced by Eu

3+

ions in our samples.It was found that the MgAlEuCO

3

-HTlcs compound is a novel dual-function material with selectivity absorbing infrared wavelength and red luminescence.