“…28 In contrast to free organoammonium cations templating conventional metal halide hybrids, our group has employed organocarboxylate anions as structuraldirecting agents to synthesize a class of ultrastable, cationic lead halide hybrids, including 3D [Pb 4 Br 6 ] 2+ frameworks, 2D [Pb 2 X 2 ] 2+ (X: Cl − /Br − ) layered materials, and open frameworks containing 1D [Pb 2 X 3 ] + (X: Cl − /Br − /I − ) chains. [29][30][31] The strong Pb-carboxylate linkages largely contribute to the high environmental moisture stability, and some of the cationic materials are even stable in a wide range of pH (3∼10) as well as aqueous boiling conditions for 24 h. 30,32,33 Moreover, the cationic haloplumbate units have strong structural strains over UV excitation, affording self-trapped, broadband white-light emissions despite low efficiencies (PLQY of 1∼15%). 31,34,35 Thus, the PLQYs of these cationic lead halide materials must be increased for commercial lighting applications.…”