The efficiency and stability of perovskite solar cells are affected by the Pb–I antisite and uncoordinated Pb0 defects existing at the interface. Directional management of Pb-based defects can reduce the defect density and voltage loss. In this work, to settle the Pb-based defects at the interface for further stabilization of the perovskite surface, we propose the strategy of designing a low-dimensional perovskite (LDP) by an amphoteric heterocyclic cation which can increase the defect formation energies and inhibit the generation of Pb–I antisite defects. The growth of the mixed-phase LDP can introduce a strong interaction with undercoordinated Pb2+ upon the surface of peroskite films accomplished with the ability of dealing with different types of surface-terminating ends. The modified devices showed an increased efficiency of 24.07% (stabilized efficiency of 23.25%) as well as improved overall stability. This opens up a direction for prompting the practical application of perovskite photovoltaic devices based on the directional management of Pb-based interface defects.

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2D perovskites have attracted extensive attention due to their excellent stability compared with 3D perovskites. However, the intrinsic hydrophilicity of introduced alkylammonium salts effects the humidity stability of 2D/3D perovskites. Devices based on longer chain alkylammonium salts show improvement in hydrophobicity but lower efficiency due to the poorer charge transport among various layers. To solve this issue, two hydrophobic short-chain alkylammonium salts with halogen functional groups (2-chloroethylamine, CEA + and 2-bromoethylamine, BEA + ) are introduced into (Cs 0.1 FA 0.9 )Pb(I 0.9 Br 0.1 ) 3 3D perovskites to form 2D/3D perovskite structure, which achieve high-quality perovskite films with better crystallization and morphology. The optimal 2D/3D perovskite solar cells (PSCs) with 5% CEA + display a power conversion efficiency (PCE) as high as 20.08% under 1 sun irradiation. Because of the notable hydrophobicity of alkylammonium cations with halogen functional groups and the formed 2D/3D perovskite structure, the optimal PSCs exhibit superior moisture resistance and retain 92% initial PCE after aging at 50 ± 5% relative humidity for 2400 h. This work opens up a new direction for the design of new-type 2D/3D PSCs with improved performance by employing proper alkylammonium salts with different functional groups.

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Mixed lead–tin perovskite solar cells (LTPSCs) with an ideal bandgap are demonstrated as a promising candidate to reach higher power conversion efficiency (PCE) than their Pb‐counterparts. Herein, a Br‐free mixed lead–tin perovskite material, FA0.8MA0.2Pb0.8Sn0.2I3, with a bandgap of 1.33 eV, as a perovskite absorber, is selected. Through density functional theory calculations and optoelectronic techniques, it is demonstrated that both Pb‐ and Sn‐related A‐site vacancies are pushed into deeper energetic depth, causing severe nonradiative recombination. Hence, a selective targeting anchor strategy that employs phenethylammonium iodide and ethylenediamine diiodide as co‐modifiers to selectively anchor with Pb‐ and Sn‐related active sites and passivate bimetallic traps, respectively, is established. Furthermore, the selectivity of the molecular oriented anchor passivation is demonstrated through energetic depth specificity of Pb‐ and Sn‐related traps. As a result, a substantially enhanced open‐circuit voltage (VOC) from 0.79 to 0.90 V for the LTPSCs is achieved, yielding a champion PCE of 22.51%, which is the highest PCE among the reported ideal‐bandgap PSCs. The VOC loss is reduced to 0.43 V.

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On Xisha Islands, located in the South China Sea, the Neogene succession includes the unconformity-bounded Huangliu Formation that is 210.5 m thick in well CK-2 and formed almost entirely of dolostones. The diverse biota in the Huangliu Formation, which includes corals, algae, bivalves and foraminifera, indicates that the original carbonate sediments accumulated in water that was < 30 m deep. The dolostones are formed of various mixtures of low-and high-calcium calcian dolomite with limpid dolomite lining the walls of many cavities.The 18 O and 13 C stable isotopes suggest that dolomitization was mediated by slightly modified seawater. The 87 Sr/ 86 Sr ratios from the dolostones suggest that dolomitization took place ~9.4 and 2.3 Ma ago, with the age of dolomitization becoming progressively younger towards the top of the formation. "Island dolostones" like these, found on many islands throughout the Pacific Ocean and the Caribbean Sea, have commonly been linked to eustatic changes in sea-level with dolomitization taking place during lowstands, highstand, or transgressive phases. Data from the Huangliu Formation in well CK-2 suggests that dolomitization was associated with (semi-)continuous transgressive conditions that were controlled by the interaction of tectonic subsidence and eustatic changes in sea level.

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