Electroluminescent devices incorporating mixed metal organic complexes
An electroluminescent device in which there is an electroluminescent which comprises a complex of general formula (L α ) n M 1 M 2 or of general formula (L α ) n M 1 M 2 (L p ), where L p is a neutral ligand and where M 1 is a rare earth, transition metal, lanthamide or an actimide, M 2 is a non rare earth metal, L α is an organic complex and n is the combined valence state of M 1 and M 2 .
1. An electroluminescent device comprising:
(i) a first electrode;
(ii) a second electrode: and,
(iii) a layer of an electroluminescent material positioned between said first and second electrodes, wherein said electroluminescent material is selected from the group consisting of materials having the general chemical formula (L α ) n M 1 M 2 and materials having the general chemical formula (L α ) n M 1 M 2 (L p ) wherein:
M 1 is selected from the group consisting of Sm(III), Eu(II), Eu(III), Tb(III), Dy(III), Yb(III), Lu(III), Gd(III), Tm(III), Th(IV), Ce(III), Ce(IV), Pr(III), Nd(III), Pm(III), Dy(III), Ho(III) or Er(III);
M 2 is selected from the group consisting of lithium, sodium, potassium, rubidium, caesium, magnesium, calcium, strontium, barium, boron, aluminum, gallium, indium, germanium, tin, lead, scandium, titanium, vanadium, chromium, nickel, copper, zinc, yttrium, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, tantalum, osmium, iridium, platinum and gold;
n is an integer equal to the combined valence state of M 1 and M 2 ;
L α is selected from the group of materials consisting of (a) to (f) as follows:
wherein R 1 and R 2 can be the same or different and are independently selected from the group consisting of hydrogen; substituted or unsubstituted aliphatic groups; substituted or unsubstituted aromatic, heterocyclic or polycyclic ring structures; fluorocarbon groups; and halogens;
X is selected from the group consisting of Se, S, and O; and,
Y is selected from the group consisting of hydrogen; substituted or unsubstituted aliphatic groups; substituted or unsubstituted aromatic, heterocyclic or polycyclic ring structures; fluorocarbon groups; halogens; and nitrile;
wherein R is selected from the group consisting of hydrocarbyl groups, aliphatic groups, aromatic groups, heterocyclic groups, carboxy groups, aryloxy groups, hydroxy groups and alkoxy groups;
wherein R 5 is selected from the group consisting of substituted or unsubstituted aromatic groups, heterocyclic groups and polycyclic rings;
wherein R 1 and R 2 are as defined in (a) above;
wherein R 1 and R 2 are as defined in (a) above; and,
wherein R is selected from the group consisting of hydrocarbyl groups, aliphatic groups, aromatic groups, heterocyclic groups, carboxy groups, aryloxy groups, hydroxyl groups and alkoxy groups; and,
Lp is selected from the group of materials consisting of (g) to (jj) as follows:
wherein each Ph group can be the same or different and are independently selected from the group consisting of substituted or unsubstituted aromatic groups and substituted or unsubstituted heterocyclic or polycyclic groups with substituents selected from alkyl, aralkyl, alkoxy, aromatic, heterocyclic, and polycyclic groups, halogens, cyano groups, and substituted or unsubstituted amino groups; and,
Z is selected from O and S;
wherein R 1 , R 2 and R 3 can be the same or different and are independently selected from the group consisting of hydrogen; substituted or unsubstituted aliphatic groups; substituted and unsubstituted aromatic, heterocyclic and polycyclic ring structures; fluorocarbon groups and halogens;
wherein R is selected from the group consisting of hydrocarbyl groups, aliphatic groups, aromatic groups, heterocyclic groups, carboxy groups, aryloxy groups, hydroxyl groups and alkoxy groups.
2. The electroluminescent device according to claim 1 wherein the electroluminescent material comprises EuZn(DBM) 5 OPNP.
3. The electroluminescent device according to claim 1 wherein the electroluminescent material comprises EuAl(DBM) 6 OPNP.
4. The electroluminescent device according to claim 1 wherein the electroluminescent material comprises EuSc(DBM) 6 OPNP.
5. The electroluminescent device according to claim 1 wherein a layer of a hole transmitting material is positioned between the first electrode and the layer of the electroluminescent material.
6. The electroluminescent device according to claim 5 wherein the hole transmitting layer is formed from a material selected from the group consisting of poly(vinylcarbazole), N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4′diamine (TPD), polyaniline, and a substituted polyaniline.
7. The electroluminescent device according to claim 1 wherein a layer of an electron transmitting material is positioned between the second electrode and the layer of electroluminescent material.
8. The electroluminescent device according to claim 7 wherein the electron transmitting material is a metal quinolate.
9. The electroluminescent device according to claim 8 wherein the metal quinolate is selected from the group consisting of lithium quinolate, sodium quinolate, potassium quinolate, zinc quinolate, magnesium quinolate and aluminum quinolate.
10. The electroluminescent device according to claim 1 wherein a layer of a hole transmitting material is positioned between the first electrode and the layer of the electroluminescent material, and further wherein a layer of an electron transmitting material is positioned between the second electrode and the layer of electroluminescent material.
11. The electroluminescent device according to claim 10 wherein the hole transmitting layer comprises a copper phthalocyanine layer and the electron transmitting layer comprises lithium fluoride.