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In this paper, we demonstrate a new method to pattern perovskites using a dry lift-off process. By utilizing parylene-C as a sacrificial layer, patterns with <12 um features and multi-color patterns can be achieved. 

A green‐emitting perovskite first‐order distributed feedback (DFB) laser based on the methylammonium lead bromide (MAPbBr₃) with high stability is demonstrated for the first time. The laser achieves stable lasing at 550 nm with a full width at half maximum of 0.4 nm. Low lasing threshold of 60 μJ cm⁻²under nanosecond pulsed excitation and 3.1 μJ cm⁻²under femtosecond pulsed excitation is observed, showing a much lower lasing threshold compared with the second‐order DFB cavities, which are fabricated on the same substrate. By optimizing the antisolvent treatment and encapsulating with poly(methyl methacrylate), the laser lifetime, resistance to moisture, lasing threshold, and intensity are significantly improved. The lasers are fabricated with a complementary metal‐oxide‐semiconductor‐compatible process, thus offer promising potential for the integrated photonic devices. 

Abstract The broad implementation of thermoelectricity requires high‐performance and low‐cost materials. One possibility is employing surfactant‐free solution synthesis to produce nanopowders. We propose the strategy of functionalizing “naked” particles’ surface by inorganic molecules to control the nanostructure and, consequently, thermoelectric performance. In particular, we use bismuth thiolates to functionalize surfactant‐free SnTe particles’ surfaces. Upon thermal processing, bismuth thiolates decomposition renders SnTe‐Bi₂S₃nanocomposites with synergistic functions: 1) carrier concentration optimization by Bi doping; 2) Seebeck coefficient enhancement and bipolar effect suppression by energy filtering; and 3) lattice thermal conductivity reduction by small grain domains, grain boundaries and nanostructuration. Overall, the SnTe‐Bi₂S₃nanocomposites exhibit peakz Tup to 1.3 at 873 K and an averagez Tof ≈0.6 at 300–873 K, which is among the highest reported for solution‐processed SnTe.