Frontispiece: Lead‐Free Metal Halide Perovskite Nanocrystals: From Fundamentals to Applications

Size‐ and Temperature‐Dependent Lattice Anisotropy and Structural Distortion in CsPbBr3 Quantum Dots by Reciprocal Space X‐ray Total Scattering Analysis

“…LHP NCs differ vastly from classical colloidal quantum dots (QDs), foremost owing to the intrinsic lattice softness and dynamics as a major feature of LHP. [42][43][44][45][46] Besides the facile (isovalent) anion and cation substitutions (for X and A sites of the APbX 3 formulation), [47][48][49][50][51][52][53][54] favoured by the presence of point defects (vacancies) with low formation energy, [27] LHP NCs are prone to accommodate both larger lattice distortions and different types of structural (static and dynamic) disorders than classical QDs. [4] Nonetheless, only a limited number of studies focus on specific size-dependent structural effects in CH 3 NH 3 PbI 3 and CsPbI 3 NCs which are concurrent to quantum confinement but influence the energy bandgap and emission properties in a distinctive way.…”

Fermi–Dirac statistics in correlation between electronic entropy and spatial confinement of liquid crystal-perovskite nanohybrids

“…4 However, due to the intrinsic toxicity of Pb, recent studies have focused on the replacement of Pb by relatively less toxic cations, such as Sn, Ge, Sb, and Bi. 5 Amongst the divalent metal cations, Sn being the group-14 element has been relevant as the most apparent substitute for Pb because of its similarity in ionic radius (Pb: 1.49 Å and Sn: 1.35 Å) as well as ns 2 electronic configuration to Pb 2+ . 6 Tin-based metal halide perovskites, viz., cesium tin chloride (CsSnCl 3 ) possess a smaller band gap (E g ) (B2.9 eV) compared to their lead counterparts, an absorption edge in the nearinfrared region (900-1000 nm), and a high light-harvesting coefficient that makes these halides viable for high performance and cost-effective electronic 7 and photovoltaic 8,9 devices.…”

Quantum-confined bismuth iodide perovskite nanocrystals in mesoporous matrices

“…7 BiHPs NCs that are Pb-free, have high photoluminescence (PL) quantum yields, and relatively low polydispersity have also been actively synthesized, mainly by hot-injection or ligandassisted reprecipitation approaches. 3,8 Colloidal NCs are typically synthesized in solution using surface ligands for stabilization. Meanwhile, the presence of ligands on the surface of nanoparticles can hinder charge transfer in photocatalytic systems.…”