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Herein, we develop an effective approach for incorporating lead (Pb) ions into manganese (Mn) halide perovskite-analogue nanocrystals (PA NCs) of CsMn(Cl/Br)3·2H2O via room-temperature supersaturation recrystallization. Pb2+-incorporated Mn-PA NCs exhibit strong orange emission upon UV light illumination, a peak centered at 600 nm assigned to Mn2+ transition (4T1g → 6A1g) with a photoluminescence quantum yield (PLQY) of 41.8% compared to the pristine Mn-PA NCs with very weak PL (PLQY = 0.10%). The significant enhancement of PLQY is attributed to the formation of [Mn(Cl/Br)4(OH)2]4--[Pb(Cl/Br)4(OH)2]4--[Mn(Cl/Br)4(OH)2]4- chain network structure, in which Pb2+ effectively dilutes the Mn2+ concentration to reduce magnetic coupling between Mn2+ pairs to relax the spin and parity selection rules. In addition, excited energy can effectively transfer from the [Pb(Cl/Br)4(OH)2]4- unit to Mn2+ luminescence centers owing to the low activation energy. Pb2+-incorporated PA NCs also exhibit excellent stability. The combined strong PL and high stability make Pb2+-incorporated Mn-based PA NCs an excellent candidate for potential optronic applications.

Background: Early life adversity (ELA) is not uncommon in major depressive disorder (MDD) patients. Childhood trauma has been reported more frequently in adult MDD patients relative to healthy controls. Recent researches have demonstrated that ELA could result in changes in brain morphology which might be an aetiological factor of MDD development. Materials and methods: We recruited 40 young adult patients suffered from MDD and made computed tomography scan. Subjects were divided in two groups: MDD patients with ELA experience (E+D) vs. MDD patients without ELA experience (E–D) according to Chinese version-Childhood Trauma Questionnaire (CTQ). 17-item Hamilton Depression (HAMD) Scale and Neuropsychiatric Inventory (NPI) were also examined. Student’s t-test was used to compare the HAMD scores, NPI scores, CTQ subcomponents scores, third ventricular (TV) width and volume of patients from E+D and E–D groups. Results: Findings demonstrated that ELA might result in TV enlargement; furthermore, there was a correlation between physical neglect and TV volume. Conclusions: These findings supported the hypothesis that ELA could induce changes of structure around the TV, which might undermine the aetiology of MDD.