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A photocatalytic system containing a perylene bisimide (PBI) dye as a photosensitizer anchored to titanium dioxide (TiO2) nanoparticles through carboxyl groups was constructed. Under solar‐light irradiation in the presence of sacrificial triethanolamine (TEOA) in neutral and basic conditions (pH 8.5), a reaction cascade is initiated in which the PBI molecule first absorbs green light, giving the formation of a stable radical anion (PBI.−), which in a second step absorbs near‐infrared light, forming a stable PBI dianion (PBI2−). Finally, the dianion absorbs red light and injects an electron into the TiO2 nanoparticle that is coated with platinum co‐catalyst for hydrogen evolution. The hydrogen evolution rates (HERs) are as high as 1216 and 1022 μmol h−1 g−1 with simulated sunlight irradiation in neutral and basic conditions, respectively. [ABSTRACT FROM AUTHOR]

The slow response speed and instability of the lateral photodetectors (L-PDs), often caused by the persistence of the excess minority carriers in the long channel after the termination of the illumination (called Persistent Photoconductivity effects) are the main factors that hinder the practical application of this type of device. In this research, two types of ZnO with different work functions, including ZnO nanoparticles (ZnO-NPs) doped in bulk heterojunction (BHJ) and thermal annealed ZnO nanocrystalline film (ZnO–NF), are incorporated into the L-PDs to construct an energy gradient, which could facilitate the quick transfer of the minority carriers and restrict their release into the active layer. The structure of L-PDs are optimized as quartz/ZnO–NF/PffBT4T-2OD:PC 61 BM:ZnO-NPs (component ratio = 5:6:1)/Au–Au electrodes. Compared with the control device, the test results show that the optimized L-PDs exhibit higher stability with much lower fall time (3.7 ms, boosted 200-fold) and gentler rise slope of dark current versus time (K dark) (8.3 × 10−6 nA/s, reduced four orders of magnitude). Meanwhile, the very low dark current (<5.5 × 10−13 A) of L-PDs allows the specific detectivity (D *) to be maintained at a high level (1.1 × 1015–6.7 × 1015 Jones) with a wide wavelength range (from 410 to 690 nm) under 4.4 μW/cm2. Therefore, the gradient trapping strategy shows promising application potential. Two types of ZnO with different work functions, including ZnO-NPs doped in bulk heterojunction (BHJ) and thermal annealed ZnO nanocrystalline film (ZnO–NF), are incorporated into the organic lateral photodetectors (L-PDs) to construct an energy gradient. The energy level gradient trapping could facilitate the quick transfer of the minority carriers and restrict their release into the active layer, enhancing the response speed of the L-PDs. Image 1 • Two types of ZnO with different work functions are incorporated into the L-PDs to construct an energy gradient. • The energy level gradient trapping could facilitate the quick transfer of the minority carriers, enhancing the response speed of the L-PDs. • The optimized L-PDs exhibit higher stability with lower fall time and gentler rise slope of dark current versus time (reduce four orders of magnitude). [ABSTRACT FROM AUTHOR]