Organic electroluminescent material and device thereof

An organic electroluminescent device, comprising a cathode, an anode, and an organic layer disposed between the cathode and the anode;

• the organic layer comprises a first emissive layer, and the first emissive layer comprises a first compound and a first metal complex;
• the capacitance characteristic of the organic electroluminescent device satisfies the following conditions:
• at 500 Hz, a maximum value of a capacitance of the organic electroluminescent device is Cmax;
• and
• at 500 Hz, a maximum value of a capacitance of an organic electroluminescent device using compound GH0 to replace the first compound in the first emissive layer is Cmax0;
• wherein Cmax−Cmax0≤−0.35 nF;
• the first metal complex has a general formula of M(La)m(Lb)n(Lc)q;
• M is selected from a metal with a relative atomic mass greater than 40;
• La, Lb, and Lc are a first ligand, a second ligand, and a third ligand coordinated to the metal M, respectively, and La, Lb, and Lc are identical or different;
• wherein La, Lb, and Lc can be optionally joined to form a tetradentate ligand or a multidentate ligand;
• m is selected from 1, 2 or 3, n is selected from 0, 1 or 2, q is selected from 0, 1 or 2, and m+n+q equals an oxidation state of the metal M;
• when m is greater than or equal to 2, a plurality of La are identical or different;
• when n is equal to 2, two Lb are identical or different;
• when q is equal to 2, two Lc are identical or different;
• the ligand La has a structure represented by Formula 1:
• wherein
• Z is selected from the group consisting of O, S, Se, NR, CRR, SiRR, and GeRR;
• when two R are present, the two R are identical or different;
• G1 and G2 are, at each occurrence identically or differently, selected from a single bond, O or S;
• two of X1 to X4 are selected from C, one of the two C is joined to the N-containing ring shown in Formula 1, the other one of the two C is joined to the metal via G2, and the remaining two of X1 to X4 are each independently selected from CRx;
• X5 to X8 are, at each occurrence identically or differently, selected from CRx;
• Y1 to Y4 are, at each occurrence identically or differently, selected from CRy or N;
• R, Rx, and Ry are, at each occurrence identically or differently, selected from the group consisting of:
• hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;
• adjacent substituents R, Rx, and Ry can be optionally joined to form a ring;
• and
• Lb and Lc are, at each occurrence identically or differently, selected from a monoanionic multidentate ligand.