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Color-stable, high-efficiency fluorescent pure-white organic light-emitting diodes were fabricated using an electroluminescence-efficient blue host 2-(N,N-diphenylamino)-6-[4-(N,N-diphenylamino)styryl]naphthalene and yellow 5,6,11,12–tetra-phenylnaphthacene in a single emissive layer. The resultant power efficiency, at 100cd∕m2, for example, was 9.5lm∕W, and its emission changed from (0.321, 0.357) to (0.315, 0.344) for brightness increasing from 100to10000cd∕m2. The high color stability may be attributed to the device structure enabling the generation of excitons on host so that lesser excitons would form on guest, preventing exciton-quenching-caused blueshift.

A relatively high‐efficiency, fluorescent pure‐white organic light‐emitting diode was fabricated using a polysilicic acid (PSA) nanodot‐embedded polymeric hole‐transporting layer (HTL). The diode employed a mixed host in the single emissive layer, which comprised 0.5 wt % yellow 5,6,11,12‐tetra‐phenylnaphthacene doped in the mixed host of 50 % 2‐(N,N‐diphenyl‐amino)‐6‐[4‐(N,N‐diphenylamino)styryl]naphthalene and 50 % N,N′‐bis‐(1‐naphthyl)‐N,N′‐diphenyl‐1,10‐biphenyl‐4‐4′‐diamine. By incorporating 7 wt % 3 nm PSA nanodot into the HTL of poly(3,4‐ethylene‐dioxythiophene)‐poly‐(styrenesulfonate), the efficiency at 100 cd m–2 was increased from 13.5 lm W–1 (14.7 cd A–1; EQE: 7.2 %) to 17.1 lm W–1 (17.6 cd A–1; EQE: 8.3 %). The marked efficiency improvement may be attributed to the introduction of the PSA nanodot, leading to a better carrier‐injection‐balance.

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