An acceptor–donor–acceptor (A–D–A)‐type non‐fullerene acceptor (NFA), PTTtID‐Cl, featuring thieno[3,2‐b]thieno[2′′′,3′′′:4′′,5′′]‐pyrrolo[2′′,3′′:4′,5′]thieno[2′,3′:4,5]thieno‐[2,3‐d]pyrrole (DTPTt) as the electron‐rich core and 2‐(5,6‐dichloro‐3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐ylidene)malononitrile (ID‐Cl) as the peripheral electron‐deficient terminal group was synthesized and characterized. PTTtID‐Cl exhibited strong absorption in the range of 700–850 nm in CHCl3 and redshifted absorption centered at 881 nm in a thin film. The near infrared (NIR)‐absorption of PTTtID‐Cl was combined with a low‐bandgap polymer donor (PTB7‐Th) to achieve binary and semitransparent organic photovoltaics (OPVs) with a power conversion efficiency (PCE) of 8.9 % and 7.7 % (with an average visible transmittance (AVT) of 16.7 %), respectively. A ternary device with a ratio of PM7/PTTtID‐Cl/IT‐4F=1:0.15:0.85 (w/w) achieved a short‐circuit current density of 19.46 mA cm−2, an open‐circuit voltage of 0.87 V, and a fill factor of 71.2 %, giving a PCE of 12.0 %. In addition, by employing the Ag/ITO/Ag microcavity structure, semitransparent colorful binary organic photovoltaics (OPVs) with superior transparency of 27.9 % at 427 nm and 22.7 % at 536 nm for blue and green devices, respectively, were prepared. The semitransparent colorful devices based on the optimized ternary blend gave PCEs of 8.7 %, 8.4 %, and 9.1 % for blue, green, and red devices, respectively. These results indicate the promising potential of PTTtID‐Cl as a NIR‐absorption NFA for applications in semitransparent colorful binary and ternary OPVs.

Organic hybrid perovskite‐based photosensors generally display high responsivities and ultrafast response speeds, but their high dark currents with low detectivities have impeded their commercial applications. In this study, these problems are overcome by modifying the device structure and performing defect passivation of the perovskite. An inverted ITO/NiOx/perovskite/PCBM/BCP/Ag structure is applied to minimize the leakage current from the interlayers. In addition, a urea additive is embedded and the thickness of the perovskite layer is optimized, resulting in an ultralow dark current (<2 pA), a peak detectivity of greater than 1.42 × 1014 Jones, and a high linear dynamic range (LDR) of up to 162 dB (in the response range from 20.25 to 6.80 × 10‐8 mW cm‐2). Using high‐purity color filters, combined with a well‐defined white light illumination system derived from a 3A solar simulator, the photosensitivity is evaluated under light of various hues and intensities (down to 10‐9 mW cm‐2). The optimized color sensors under blue, green, orange, and red hues of light display LDRs of greater than 139 dB in the mesopic vision regime (wavelengths: 400–700 nm) between 10‐6 and 10‐3 mW cm‐2—outperforming human visual color perception.

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TaN–Cu nanocomposite films were deposited by reactive cosputtering on Si and tool steel substrates. The films were then annealed using rapid thermal annealing (RTA) at 400°C for 2, 4, and 8min, respectively, to induce the nucleation and growth of Cu particles in TaN matrix and on film surface. Field emission scanning electron microscopy was applied to characterize Cu nanoparticles emerged on the surface of TaN–Cu thin films. The effects of annealing on the antiwear and antibacterial properties of these films were studied. The results reveal that annealing by RTA can cause Cu nanoparticles to form on the TaN surface. Consequently, the tribological behaviors, as well as the antibacterial behavior may vary depending on particle size, particle distribution, and total exposed Cu amount. For the samples with large Cu particles, the reduction of averaged friction and wear rate is obvious. Apparently, it is due to the smeared Cu particles adhered onto the wear tracks. This Cu layer may act as a solid lubricant. From the antibacterial testing results, it is found that both Cu particle size and total exposed Cu amount are critical in making short-term antibacterial effect. Overall, all the annealed TaN–Cu samples can reach &gt;99% antibacterial efficiency in 24h, with respect to uncoated Si substrate.