Composition, OLED device and OLED display panel

An OLED device, comprising:

• an anode layer, a cathode layer, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer which are sequentially stacked along a direction from the anode layer to the cathode layer;
• wherein the electron transport layer comprises a low-mobility metal complex material of bias-electron-transport-type in a mass percentage of 1% to 99% and an organic electron transport material in a mass percentage of 1% to 99%, wherein an electron mobility of the low-mobility metal complex material of bias-electron-transport-type is less than 1*E−7 cm2/Vs;
• wherein the low-mobility metal complex material of bias-electron-transport-type comprises any one of a carbonic acid group, a trimethylacetic acid group, an oxalic acid group, a phenolic acid group and a fluoride group or a derivative thereof.