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Creators/Authors contains: "Spanopoulos, Ioannis"

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  1. Free, publicly-accessible full text available March 14, 2026
  2. null (Ed.)
  3. Abstract 2D hybrid organic–inorganic perovskites (HOIPs) are commonly found under subcritical cyclic stresses and suffer from fatigue issues during device operation. However, their fatigue properties remain unknown. Here, the fatigue behavior of (C4H9‐NH3)2(CH3NH3)2Pb3I10, the archetype 2D HOIP, is systematically investigated by atomic force microscopy (AFM). It is found that 2D HOIPs are much more fatigue resilient than polymers and can survive over 1 billion cycles. 2D HOIPs tend to exhibit brittle failure at high mean stress levels, but behave as ductile materials at low mean stress levels. These results suggest the presence of a plastic deformation mechanism in these ionic 2D HOIPs at low mean stress levels, which may contribute to the long fatigue lifetime, but is inhibited at higher mean stresses. The stiffness and strength of 2D HOIPs are gradually weakened under subcritical loading, potentially as a result of stress‐induced defect nucleation and accumulation. The cyclic loading component can further accelerate this process. The fatigue lifetime of 2D HOIPs can be extended by reducing the mean stress, stress amplitude, or increasing the thickness. These results can provide indispensable insights into designing and engineering 2D HOIPs and other hybrid organic–inorganic materials for long‐term mechanical durability. 
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  4. The sorption properties of [Zr 6 O 4 (OH) 4 (NH 3 + -BDC) 6 ]Cl 6 · x H 2 O ( MOR-1 ) and H 16 [Zr 6 O 16 (H 2 PATP) 4 ]Cl 8 · x H 2 O ( MOR-2 ) towards ReO 4 − and TcO 4 − were studied in detail. Both MOR-1 and MOR-2 are very effective sorbents for ReO 4 − and TcO 4 − anions, with MOR-2 showing the highest sorption capacity (up to 4.1 ± 0.4 mmol g −1 ) among the known metal organic materials. Importantly, the exceptional sorption capacity of MOR-2 is retained even under conditions simulating acidic nuclear waste. In addition, MOR-1 and MOR-2 exhibit selective luminescence ReO 4 − sensing properties, demonstrated for the first time for MOF materials. 
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