Quantum dot composition and quantum dot light-emitting device

A quantum dot light-emitting device comprising:

• an anode, a hole transport layer, a quantum dot light-emitting layer, and a cathode, which are sequentially stacked;
• wherein the quantum dot light-emitting layer comprises the quantum dot composition comprising a first quantum dot and a second quantum dot, the first quantum dot and the second quantum dot are both core-shell quantum dots;
• a ratio of a conduction band energy level of a core of the first quantum dot to a conduction band energy level of a core of the second quantum dot is 1:(0.9-1.1), and a ratio of a valence band energy level of the core of the first quantum dot to a valence band energy level of the core of the second quantum dot is 1:(0.9-1.1);
• or a ratio of a band gap width of a core of the first quantum dot to a band gap width of a core of the second quantum dot is 1:(0.9-1.1);
• a conduction band energy level of an outermost shell of the second quantum dot is lower than a conduction band energy level of an outermost shell of the first quantum dot, and a valence band energy level of the outermost shell of the second quantum dot is lower than a valence band energy level of the outermost shell of the first quantum dot;
• wherein the first quantum dot satisfies 0<ΔEVB,C1-S1≤0.4 eV and ΔECB,S1-C1>0.4 eV, and the second quantum dot satisfies 0<ΔECB,S2-C2<0.4 eV and ΔEVB,C2-S2>0.4 eV;
• ΔEVB,C1-S1=EVB,C1−EVB,S1, ΔECB,S1-C1=ECB,S1−ECB,C1, ΔEVB,C2-S2=EVB,C2−EVB,S2, ΔECB,S2-C2=ECB,S2−ECB,C2, where C1, S1, C2, and S2 respectively represent the core and the shell of the first quantum dot and the core and the shell of the second quantum dot.