[1] Zhao Y B, Chen J S, Ma D G. Realization of high efficiency orange and white organic light emitting diodes by introducing an ultra-thin undoped orange emitting layer[J]. Applied Physics Letters, 99, 163303(2011).
[2] Yang F Y, Kou Z Q, Yang L P et al. Influence of the hole transport layer on spectral stability in the white phosphorescent organic light emitting diode with non-doped structure[J]. Optical Materials, 82, 130-134(2018).
[3] Schwartz G, Reineke S, Rosenow T C et al. Triplet harvesting in hybrid white organic light-emitting diodes[J]. Advanced Functional Materials, 19, 1319-1333(2009).
[7] Sun N, Zhao Y B, Zhao F C et al. A white organic light-emitting diode with ultra-high color rendering index, high efficiency, and extremely low efficiency roll-off[J]. Applied Physics Letters, 105, 013303(2014).
[8] Li Z Y, Li B W, Wei X F et al. High efficiency, high color rendering index white organic light-emitting diodes based on thermally activated delayed fluorescence materials[J]. Applied Physics Letters, 115, 263302(2019).
[9] Lee S E, Oh J H, Baek H J et al. Realization of high-color-quality white-by-blue organic light-emitting diodes with yellow and red phosphor films[J]. Journal of Luminescence, 207, 195-200(2019).
[10] Wu Z B, Ma D G. Recent advances in white organic light-emitting diodes[J]. Materials Science and Engineering R, 107, 1-42(2016).
[11] Zhang W, Wu L S, Su Z S et al. Low color temperature, high color rendering index candlelight style white organic light-emitting devices with a fac-tris (mesityl-2-phenyl-1H-imidazole) iridium (III) blue emitting layer[J]. Materials Research Express, 6, 016205(2018).
[13] Luo D X, Xiao P, Liu B Q. Doping-free white organic light-emitting diodes[J]. The Chemical Record, 19, 1596-1610(2019).
[14] Yu H, Dai X, Yao F et al[J]. <1 nm) Scientific Reports, 8, 6068.
[15] Zhang T, He S J, Wang D K et al[J]. A multi-zoned white organic light-emitting diode with high CRI and low color temperature Scientific Reports, 6, 20517.
[16] Miao Y Q, Wang K X, Zhao B et al. High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer[J]. Nanophotonics, 7, 295-304(2018).
[17] Liu B Q, Tao H, Wang L et al. High-performance doping-free hybrid white organic light-emitting diodes: the exploitation of ultrathin emitting nanolayers (<1 nm)[J]. Nano Energy, 26, 26-36(2016).
[18] Wang B Q, Kou Z Q, Tang Y et al. High CRI and stable spectra white organic light-emitting diodes with double doped blue emission layers and multiple ultrathin phosphorescent emission layers by adjusting the thickness of spacer layer[J]. Organic Electronics, 70, 149-154(2019).
[19] Jankus V, Chiang C J, Dias F et al. Deep blue exciplex organic light-emitting diodes with enhanced efficiency; P-type or E-type triplet conversion to singlet excitons?[J]. Advanced Materials, 25, 1455-1459(2013).
[20] Xue K W, Chen P, Duan Y et al. Improved color stability of white organic light-emitting diodes without interlayer between red, orange and blue emission layers[J]. Optics Communications, 362, 59-63(2016).
[21] Zhang H, Yang X, Cheng J et al. Enhanced color stability for white organic light-emitting diodes based on dual ultra-thin emitting layer[J]. Organic Electronics, 50, 147-152(2017).
[22] Yun C, Lee J, Lee J et al. Influence of phosphorescent dopants in organic light-emitting diodes with an organic homojunction[J]. Applied Physics Letters, 101, 243303(2012).
[23] Tan T, Ouyang S H, Xie Y T et al. Balanced white organic light-emitting diode with non-doped ultra-thin emissive layers based on exciton management[J]. Organic Electronics, 25, 232-236(2015).