Semitransparent organic photovoltaics (ST‐OPVs) have great potential for use in renewable energy technologies. In bulk‐heterojunction (BHJ) ST‐OPVs, a compromise is necessary between the visible light transmittance (VLT) and the power conversion efficiency (PCE). A sequential deposition (SD) strategy that involves individually depositing a polymer donor layer (D) and a small‐molecule acceptor layer (A) as the active layer is presented; where molecular diffusion occurring at the interfacial region results in a pseudo p–i–n structure. PBDB‐T‐2F(D)/Y6(A) ST‐OPVs are fabricated with different active layer thicknesses—at 115 nm, the SD (D:A/75:40 nm) and BHJ devices (D:A/1:1.2 w) provide the champion PCE of 12.91% (VLT of 14.5%) and 12.77% (VLT of 13.4%), respectively; at 85 nm, the SD (D:A/45:40 nm) and BHJ devices (D:A/1:1.2 w) provide a PCE of 12.22% (VLT of 22.2%) and 11.23% (VLT of 16.6%), respectively. This trend indicates SD devices have larger PCE and VLT values than the BHJ devices at a given active layer thickness, and the enhancements of PCE and VLT values by the SD structures against the BHJ structures become more pronounced as the active layer thickness reduced. The SD strategy provides a new approach for achieving ST‐OPVs with both high efficiency and high transparency.

In this work, two polyimide/silica composites were prepared via physical blending (A series) and chemical bonding (B series) and compared for light extraction from organic light-emitting devices (OLEDs).

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In article number 2003576, Kung‐Hwa Wei and co‐workers demonstrate that semi‐transparent organic photovoltaics with a sequential deposited (SD) active layer—individually deposited polymer donor layer and a small‐molecule acceptor layer—forming pseudo p–i–n structures have larger power conversion efficiency and transmittance values than those for the devices with bulk heterojunction (BHJ) structures, and the enhancements for SD versus BHJ devices increase with the decreasing active layer thickness.

vigorously studied over the past decades since the emergence of blue LED. [1] A myriad of efficient phosphors including yellow emissive Y 3 Al 5 O 12 :Ce 3+ (YAG:Ce 3+ ), blue emissive BaMgAl 10 O 17 :Eu 2+ (BAM:Eu 2+ ), green emissive Si 6−z Al z O z N 8−z :Eu 2+ (0 < z ≤ 4.2) (β-Sialon:Eu 2+ ), and red emissive Y 2 O 3 :Eu 3+ have been commercialized and applied in indoor and outdoor illumination, traffic lights, and display backlight to name but a few. Nonetheless, the high junction temperature of LED chips (usually ≥150 °C) leads to nonradiative relaxation and diminish the luminescence efficiency of phosphors. [2] This phenomenon is widely known as thermal quenching (TQ) and is the main issue in further improving the performance and application of PC-LEDs. [2][3][4] The effect is expected to be even more severe in emerging micro-LED applications due to the proximity of phosphors with the LEDs. Furthermore, in traditional phosphors, the emission comes from atomic electron transition of earth scarce rare-earth elements, and the mining process of these elements poses a great threat to the environment and the health of the miners. [5] Therefore, the development of earth abundant emitters with high efficiency and TQ-resistant is urgent.