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Two-dimensional transition metal dichalcogenide (2D TMD) crystals are versatile platforms for realizing emergent optoelectronic devices. However, the ability to produce large-area 2D TMDs with spatial homogeneity and to accomplish broadband photodetection by tuning the operating wavelengths in photodetectors are two paramount prerequisites for practical applications of 2D TMD-based photodetectors. Here, we demonstrated all-solution-processed broadband photodetectors based on the wafer-scale perovskite quantum dots (PQDs)/MoS2 through light management via the monochromatization effect of the PQDs. The photodetectors exhibited broadband photodetection behavior that retained high photocurrents over a wide spectral range (254, 365, and 532 nm) by enhancing the photoresponse in the UV region through light management via the monochromatization effect of the PQDs. This intriguing strategy was proven with (i) electrical isolation realized by inserting an Al2O3 insulator between the PQDs and MoS2 and (ii) alteration of the PQD density. The rational nanohybrid-based photodetectors also exhibited superb air stability and exceptional bending durability.

arped disk galaxies are classified into two morphologies: S- and U-types. Conventional theories routinely attribute both types to galactic tidal interaction and/or gas accretion, but reproducing of U-types in simulations is extremely challenging. Here we investigate whether both types are governed by the same mechanisms using the most extensive sample of $\sim$8000 nearby (0.02\,$$\,$10^9$) edge-on disks from SDSS. We find that U-types show on average bluer optical colors and higher specific star formation rate (sSFR) than S-types, with more strongly warped U-types having higher sSFR. We also find that while the S-type warp properties correlate with the tidal force by the nearest neighbor regardless of the environment, there is no such correlation for U-types in groups/clusters, suggesting a non-tidal environmental could be at play for U-types, such as ram pressure stripping (RPS). Indeed, U-types are more common in groups/clusters than in fields and they have stellar mass, gas fraction, sSFR enhancement and phase-space distribution closely analogous to RPS-induced jellyfish galaxies in clusters. We furthermore show that the stellar disks of most RPS galaxies in the IllustirsTNG simulation are warped in U-shape and bent in opposite direction of stripped gas tails, satisfying theoretical expectations for stellar warps embeded in jellyfishes. We therefore suggest that despite the majority of U-types that live in fields being still less explained, RPS can be an alternative origin for those in groups/clusters., 28 pages, 15 figures, accpeted for publication in ApJ

Low‐temperature processes and simplification of lithographic techniques are key challenges for the fabrication of solution‐processed metal oxide‐based nanodevices. Recent breakthroughs in location‐specific synthetic methodologies involving inkjet printing and photon‐activation routes have enabled lithography‐free and bottom‐up fabrication of such devices. However, a revolutionary strategy to resolve room‐temperature direct fabrication of metal oxide‐based materials still remains elusive. Here, a pertinent route enabling wafer‐scale, location‐specific direct‐writing, termed “photon‐pen writing (PPW),” of functional metal oxide‐based devices is proposed. Using PPW, fabrication of elaborate patterns of metal oxides is demonstrated through location‐specific dechlorination and subsequent oxidation via thermal energy transfer of a focused infrared laser in ambient environment. By tailoring process parameters, precise manipulation of the chemical and structural features of the PPW‐produced metal‐oxide patterns are demonstrated. The versatility of the PPW process by realizing a highly sensitive, stable, uniform, and wafer‐scale nanosensor array for gas and light detection using PPW‐ZnO channel and PPW‐ITO electrodes is demonstrated, with 4.1% of response at 50 ppb NO2 and 2.93 ± 0.23 µA of photocurrent for 0.76 mW cm−2, 254 nm UV light. A new route toward wafer‐scale production of bespoke nanosensor arrays onto single chip for next‐generation nanoelectronics is introduced.

Funder: Alphasense Limited, Selectivity for specific analytes and high‐temperature operation are key challenges for chemiresistive‐type gas sensors. Complementary hybrid materials, such as reduced graphene oxide (rGO) decorated with metal oxides enables realization of room‐temperature sensors with enhanced sensitivity. However, sensor training to identify target gases and accurate concentration measurement from gas mixtures still remain very challenging. This work proposes hybridization of rGO with CuCoO x binary metal oxide as a sensing material. Highly stable, room‐temperature NO2 sensors with a 50 ppb of detection limit is demonstrated using inkjet printing. A framework is then developed for machine‐intelligent recognition with good visibility to identify specific gases and predict concentration under an interfering atmosphere from a single sensor. Using ten unique parameters extracted from the sensor response, the machine learning‐based classifier provides a decision boundary with 98.1% accuracy, and is able to correctly predict previously unseen NO2 and humidity concentrations in an interfering environment. This approach enables implementation of an intelligent platform for printable, room‐temperature gas sensors in a mixed environment irrespective of ambient humidity.