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The combination of a sol–gel precursor approach and microwave heating leads to a hitherto unknown MAX phase Cr₂GaC_1−xN_x. Magnetic measurements reveal that the susceptibility depends on the nitrogen amount on the X-site. 

Abstract Hybrid organic–inorganic perovskites enable the production of semiconductor devices at low cost from solution processing. Their remarkable structural versatility offers unique and diverse physical properties, leading to their incorporation in a wide variety of applications. One major limitation is the significant negative environmental impact associated with developing perovskite devices; common solvents used in perovskite film deposition are highly toxic, which represents a barrier to the transfer to an industrial setting of the perovskite technology. Here we report on the fabrication and characterisation of the first laser printed organic–inorganic perovskite films. The method is solvent-free, scalable and low-cost, allowing fast deposition over large areas and with minimal material waste. We show that the laser printed perovskite films are crystalline and exhibit electrical properties on par with single crystals, despite the fact that the microstructure consists of randomly oriented crystallites. The toner used during printing is designed for optimal film transfer and the vertical separation of its components results in a segregation of the perovskite film in the middle of the stack, therefore also encapsulating the perovskite layer, a process that yields a remarkable resilience to defect formation upon environmental exposure. 

Abstract We present the occurrence rates for rocky planets in the habitable zones (HZs) of main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and Gaia-based stellar properties. We provide the first analysis in terms of star-dependent instellation flux, which allows us to track HZ planets. We define η ⊕ as the HZ occurrence of planets with radii between 0.5 and 1.5 R ⊕ orbiting stars with effective temperatures between 4800 and 6300 K. We find that η ⊕ for the conservative HZ is between (errors reflect 68% credible intervals) and planets per star, while the optimistic HZ occurrence is between and planets per star. These bounds reflect two extreme assumptions about the extrapolation of completeness beyond orbital periods where DR25 completeness data are available. The large uncertainties are due to the small number of detected small HZ planets. We find similar occurrence rates between using Poisson likelihood Bayesian analysis and using Approximate Bayesian Computation. Our results are corrected for catalog completeness and reliability. Both completeness and the planet occurrence rate are dependent on stellar effective temperature. We also present occurrence rates for various stellar populations and planet size ranges. We estimate with 95% confidence that, on average, the nearest HZ planet around G and K dwarfs is ∼6 pc away and there are ∼4 HZ rocky planets around G and K dwarfs within 10 pc of the Sun.