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Bulk black phosphorous (bP) exhibits excellent infrared (IR) optoelectronic properties, but most reported bP IR photodetectors are fabricated from single exfoliated flakes with lateral sizes of < 100 µm. Here, scalable thin films of bP suitable for IR photodetector arrays are realized through a tailored solution‐deposition method. The properties of the bP film and their protective capping layers are optimized to fabricate bP IR photoconductors exhibiting specific detectivities up to 4.0 × 108 cm Hz1/2 W−1 with fast 30/60 µs rise/fall times under λ = 2.2 µm illumination. The scalability of the bP thin film fabrication is demonstrated by fabricating a linear array of 25 bP photodetectors and obtaining 25 × 25 pixel IR images at ≈203 ppi with good spatial fidelity. This research demonstrates a commercially viable method of fabricating scalable bP thin films for optoelectronic devices including room temperature‐operable IR photodetector arrays. [ABSTRACT FROM AUTHOR]

Controlled functionalization of 2D black phosphorus (BP) nanosheets provides unique opportunities to tune their chemical, physical, and electronic properties. Herein, the preparation of single‐atom nickel‐doped BP (Ni–BP) sheets using a simple solution‐based strategy is reported. Using the Ni–BP sheets as a passivation layer on top of a perovskite film leads to standard perovskite solar cells (PSCs) with improved performance. The standard n–i–p PSCs with the Ni–BP interlayer achieve maximum power conversion efficiencies of over 22%, with negligible hysteresis and a modest improvement in stability when subjected to different testing conditions. The perovskite films prepared with Ni–BP sheets‐based passivation are found to have reduced defect densities as well as improved charge‐transfer properties and carrier lifetimes. Density‐functional theory calculations support the experimental results through showing that the atomic Ni‐doping increases the work function of the BP interlayer, enabling better hole extraction, as well as increasing the surface hydrophobicity of the BP layer, hence reducing water sorption into the perovskite film. [ABSTRACT FROM AUTHOR]

Modifying light-harvesting photoactive materials via doping and/or functionalization approaches is an effective approach for enhancing the efficiency and stability of solar cells. Herein, sulfur-functionalized two-dimensional (2D) transition-metal carbide (S-MXene) nanosheets are synthesized and introduced as doping agents into the Sb2S3 light absorbers for solar cells. Furthermore, Sb2S3 solar cells are fabricated in two different experimental environments including an inert gas (argon) and ambient conditions (air) using S-MXene as the dopant. Our theoretical calculations and experimental analysis revealed that the ambient air fabrication and incorporation of conductive S-MXene can lead to an increase in the charge transport of Sb2S3 solar cells as well as introduce a p-type doping effect. Moreover, the best-performing device with S-MXene fabricated in air exhibited significant enhancement (59.65%) in the performance with respect to the S-MXene-doped cells fabricated in a glovebox filled with an inert gas. This work not only introduces the possibility of ambient air fabrication of Sb2S3 solar cells but also opens an avenue toward the development of functionalized 2D dopants for Sb2S3 solar cells. [ABSTRACT FROM AUTHOR]