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Chiral hybrid organic–inorganic metal halides (HOMHs) offer an ideal platform for the advancement of second‐order nonlinear optical (NLO) materials owing to their inherent noncentrosymmetric structures. The enhancement of optical nonlinearity of chiral HOMHs could be achieved by matching the free exciton and/or self‐trapped exciton energy levels with desired NLO frequencies. However, the current scarcity of resonance modes and low resonance ratio hamper the further improvements of NLO performance. Herein, we propose a new resonant channel of charge transfer (CT) excited states from metal halide polyhedra to organic ligand to boost the second‐order optical nonlinearity of chiral HOMHs. The model lead halide (C7H10N)PbBr3 (C7H10N=1‐ethylpyridinium) exhibits a drastically enhanced second harmonic generation in resonance to the deep CT exciton energy, with intensity of up to 111.0 times that of KDP and 10.9 times that of urea. The effective NLO coefficient has been determined to be as high as ~40.2 pm V−1, balanced with a large polarization ratio and high laser damage threshold. This work highlights the contribution of organic ligands in the construction of a resonant channel for enhancing second‐order NLO coefficients of metal halides, and thus provides guidelines for designing new chiral HOMHs materials for advanced nonlinear photonic applications. [ABSTRACT FROM AUTHOR]

Nano composite of Ruddlesden-Popper electrocatalyst-oxygen ionic conductor, (Pr 0.9 La 0.1 ) 2 (Ni 0.74 Cu 0.21 Nb 0.05 )O 4+δ (PLNCN)-Ce 0.9 Gd 0.1 O 2−δ (GDC), is developed as composite cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs) via a infiltration way. The electrochemical behavior of PLNCN-GDC nanostructured electrode is assessed with respect to infiltration loading and oxygen partial pressure. The optimized PLNCN loading can improve charge transfer dynamics for electrochemical oxygen reduction reaction, thus promoting cathode performance. Importantly, the encouraging results of single cell highlight high activity and good CO 2 tolerance of PLNCN-GDC nanostructured cathode. [ABSTRACT FROM AUTHOR]

Fluorine-free, blue-emitting cationic iridium complexes, namely [Ir(Tipr-dphoxd) 2 (bpy)]PF 6 (1) and [Ir(Tipr-dphoxd) 2 (pzpy)]PF 6 (2), which use 2-phenyl-5-(2,4,6-triisopropylphenyl)-1,3,4-oxadiazole (Tipr-dphoxd) as the cyclometalating ligand (CΛN) and 2,2’-bipyridine (bpy) or 2-(1 H -pyrazol-1-yl)pyridine (pzpy) as the ancillary ligands (NΛN), have been synthesized and fully characterized. In solution, complex 1 emits efficient blue-green light centered at 505 nm with notable charge-transfer (CT) (Ir/CΛN → NΛN) character; while in the lightly doped film, it emits efficient sky-blue light peaked at 474 and 502 nm with much CΛN-centered 3 π-π ∗ character. In both solution and films, complex 2 always emits sky-blue light peaked around 468 nm and 500 nm with dominant CΛN-centered 3 π-π ∗ character. The sky-blue light emission from complexes 1 and 2 is among the bluest reported for fluorine-free, blue-emitting cationic iridium complexes. Theoretical calculations reveal that complex 1 bears energetically close-lying CT and CΛN-centered 3 π-π ∗ states, and its emission can arise from either or both of them; while for complex 2, its emission always comes from the lowest-lying CΛN-centered 3 π-π ∗ state. Because the CT state contributes considerably to the emission of complex 1, complex 1 exhibits more rapid radiative decays, higher luminescent efficiencies and shorter excited-state lifetimes than complex 2 in both the solution and lightly doped film. Complexes 1 and 2 have been tested as emitting materials in solid-state light-emitting electrochemical cells (LECs), with red-shifted electroluminescence compared to the photoluminescence. The green-yellow LEC based on complex 1 and the blue-green LEC based on complex 2 show peak current efficiencies of 12.4 and 5.0 cd A −1 , respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • La 2 Ti 2 O 7 -In 2 O 3 photocatalyst has been constructed via the interface band structure engineering. • La 2 Ti 2 O 7 -In 2 O 3 shows excellent photocatalytic activity on CIP degradation with good photostability and recyclability. • The interfacial engineering accelerates the charge direction transfer process. • La 2 Ti 2 O 7 -In 2 O 3 can generate ·OH and ·O 2 – efficiently via Z-scheme mechanism. Interfacial regulation in solar-light-responsive heterostructures is considered an effective strategy to address efficient charge transfer. However, the conscious design of interfacial engineering is still a great challenge. Herein, sandwich-like La 2 Ti 2 O 7 /In 2 O 3 hierarchical tubular heterostructure was reasonably designed to modulate the interface structure for efficient photocatalytic ciprofloxacin degradation. Systematic investigations reveal that the Z-scheme charge transfer mechanism is affirmed using the electron paramagnetic resonance spectra, density functional theory calculations and in-situ irradiated XPS spectra. The hierarchical tubular heterostructure is responsible for improved light absorption and active sites, while the strong interfacial interaction can induce the separation and migration of photogenerated charges. Thus, the optimized photocatalyst exhibits high ciprofloxacin degradation rate of 98.2% in 100 min with a pseudo-first-order rate constant of 0.0408 min−1, which is about 98.05-fold and 38.86-fold of the pristine In 2 O 3 and La 2 Ti 2 O 7 , respectively. [ABSTRACT FROM AUTHOR]