Managing Interface Defects via Mixed-Salt Passivation toward Efficient and Stable Perovskite Solar Cells.

Iodine vacancies and uncoordinated Pb0 defects existing at the perovskite surface have been widely demonstrated to induce deep-level defects, which can greatly limit improvement of the efficiency and stability of perovskite solar cells (PSCs). In this work, a novel strategy is proposed for functionalizing perovskite surface by using trimethylsulfoxonium iodide (TMSI), which can enhance the defect formation energy and inhibit Pb0 defects. Meanwhile, TMSI modification also can fill the iodine vacancies of perovskite surface-terminating ends. Consequently, the optimized device shows the improved charge dynamics and the reduced energy losses, achieving a champion efficiency of up to 24.03% along with excellent air-storage and thermal stabilities. This work offers guidelines for more efficient and stable PSCs based on the management of interface defects.

Electrical Loss Management by Molecularly Manipulating Dopant-free Poly(3-hexylthiophene) towards 16.93 % CsPbI2 Br Solar Cells.

Inorganic cesium lead halide perovskites offer a pathway towards thermally stable photovoltaics. However, moisture-induced phase degradation restricts the application of hole transport layers (HTLs) with hygroscopic dopants. Dopant-free HTLs fail to realize efficient photovoltaics due to severe electrical loss. Herein, we developed an electrical loss management strategy by manipulating poly(3-hexylthiophene) with a small molecule, i.e., SMe-TATPyr. The developed P3HT/SMe-TATPyr HTL shows a three-time increase of carrier mobility owing to breaking the long-range ordering of "edge-on" P3HT and inducing the formation of "face-on" clusters, over 50 % decrease of the perovskite surface defect density, and a reduced voltage loss at the perovskite/HTL interface because of favorable energy level alignment. The CsPbI2 Br perovskite solar cell demonstrates a record-high efficiency of 16.93 % for dopant-free HTL, and superior moisture and thermal stability by maintaining 96 % efficiency at low-humidity condition (10-25 % R. H.) for 1500 hours and over 95 % efficiency after annealing at 85 °C for 1000 hours.

The fluorescent property of 3-[(2-hydroxy-1-naphthyl) methylideneamino]benzoic acid and its application as fluorescent chemosensor for Hg2+ and Al3+ ions.

This manuscript studies the fluorescent property of 3-[(2-hydroxy-1-naphthyl)methylideneamino]benzoic acid (H2L). Fluorescent spectra show that in different solvents, H2L displays different fluorescent properties, which can be attributed to the interaction between the solvents and H2L. Further study indicates that H2L exhibits a highly selective and sensitive recognition for Hg2+ ions in dimethylsulfoxide (DMSO), Al3+ ions in methanol and N,N'-dimethylformamide/water (DMF/H2O, 1/1, v/v). The bonding modes and bonding ratio of H2L and metal ions in different solvents are explored by Job's plot, 1H NMR titration, and electrospray ionization mass spectrometry (ESI-MS). The probable mechanisms were discussed.

In-situ synthesis of novel Z-scheme SnS(2)/BiOBr photocatalysts with superior photocatalytic efficiency under visible light.

In this study, a novel SnS2/BiOBr heterojunction photocatalyst was synthesized via a facile in-situ growth strategy. The heterojunction interface was formed by loading BiOBr nanosheets on the surface of ultrathin hexagonal SnS2 nanoplates. UV/Vis diffuse reflectance spectroscopy (DRS) indicated that SnS2/BiOBr composites possessed stronger visible-light absorption. The as-fabricated SnS2/BiOBr heterojunction nanoplates exhibited considerable improvement in terms of photocatalytic activity for the degradation of rhodamine B (RhB) under visible light irradiation as compared with BiOBr and SnS2. The enhanced photocatalytic activity was attributed to the closely contacted interface between BiOBr and SnS2, thereby resulting in faster transfer of the photoinduced electron-hole pairs through their interface, as shown by the results of photoluminescence spectroscopy (PL) and photocurrent measurements. Radical trapping experiments demonstrated that holes (h+) and superoxide anion radicals (O2-) were the main active species in the photocatalytic oxidation process. The mechanism of the excellent photocatalytic activity of SnS2/BiOBr heterojunction composite was also discussed.