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A cubic Mn 0.6 Fe 0.4 S solid solution material has been synthesized using a scalable in situ sulfuration treatment of Prussian-blue analogs (PBAs), and its phase formation process and Li-storage mechanism were investigated. Increased treatment temperature and time encourage a phase transformation from hexagonal Fe 7 S 8 to cubic FeS 2 during the sulfuration process, which results in the formation of a solid solution between cubic FeS 2 and cubic MnS. The resulting Mn 0.6 Fe 0.4 S solid solution electrode exhibits high initial coulombic efficiency, excellent rate performance, and superior cycling stability (520 mA h g−1 after 1000 cycles at 1.0 A g–1). Ex-situ X-ray diffractometry and electro-kinetics tests show that the doping-induced structural phase transition in Mn 0.6 Fe 0.4 S solid solution creates a favorable electronic structure and ensures rapid charge transfer kinetics during the lithiation/delithiation process, simultaneously achieving high energy conversion efficiency and a long lifespan. [Display omitted] • Cubic Mn 0.6 Fe 0.4 S solid solution as anode material is successfully synthesized. • The phase transition from α-MnS to metastable β-MnS could be induced in the charge process. • The improvement in electrochemical performance is attributed to the doping-induced structural phase transition in Mn0.6Fe0.4S. [ABSTRACT FROM AUTHOR]

• Zn 2 Ti 3 O 8 /ZnTiO 3 and Zn 2 TiO 4 /R-TiO 2 heterostructures were prepared through a two-step chemical route. • The heterostructure catalysts showed improved photocatalytic activities for CO 2 reduction with H 2 O. • Zn 2 Ti 3 O 8 /ZnTiO 3 and Zn 2 TiO 4 /R-TiO 2 heterojunctions favor the separation and transfer of charge carriers. • The band gap structures and the working mechanisms of Zn 2 Ti 3 O 8 /ZnTiO 3 and Zn 2 TiO 4 /R-TiO 2 heterojuntions were proposed. Photocatalytic reduction of CO 2 with H 2 O on photocatalysts to produce fuels presents great potential to simultaneously address energy and environmental issues. Herein, zinc titanate-based heterostructured nanohybrids including Zn 2 Ti 3 O 8 /ZnTiO 3 and Zn 2 TiO 4 /R-TiO 2 were designed and prepared through a two-step chemical route. When used as photocatalyst for converting CO 2 with H 2 O under UV-light irradiation, the zinc titanate-based heterostructured nanohybrids show high photocatalytic performance, with CH 4 and CO yields significantly higher than those obtained with Zn 2 Ti 3 O 8 , Zn 2 TiO 4 , and rutile TiO 2 as the photocatalysts. The existence of heterojunctions in the nanohybrids was demonstrated by experimental results, and electrochemical impedance spectra also reveal a favorable zinc titanate-based heterostructure. Moreover, based on theoretical calculations, the observed reduced band gap further revealed the effective light-absorption of the heterostructured nanohybrids in CO 2 reduction. It is thus concluded that the synergistic effect of the heterostructure promotes charge separation and fast electron transport, resulting in its enhanced photocatalytic performance in CO 2 reduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coexistence of intra-CT and inter-CT processes is realized for DPA-XA-TRZ. • Dual CT processes can be simultaneously enhanced by planar molecular skeleton. • Organic light-emitting diodes with external quantum efficiency of 21.9% is realized. • Efficiency of 31.7% is realized by DPA-XA-TRZ sensitized device with DMAc-BN dopant. Intramolecular charge transfer (intra-CT) and intermolecular charge transfer (inter-CT) are two general molecular design strategies of thermally activated delayed fluorescence (TADF) materials for organic light-emitting diodes (OLEDs). Herein, a diphenylamine (DPA) donor and a 2,4-diphenyl-1,3,5-triazine (TRZ) acceptor are connected by two planar units, non-conjugated 9,9-dimethyl-9 H -xanthene (XA) and conjugated dibenzo[ b,d ]furan (FR), to give D-σ-A type emitter DPA-XA-TRZ and D-π-A type emitter DPA-FR-TRZ. Coexistence of intra- and inter-CT is found for DPA-XA-TRZ and is readily tuned by various doping concentrations owing to the non-conjugated linkage. In contrast, DPA-FR-TRZ shows a dominant intra-CT characteristic due to the strong molecular conjugation. The planar molecular skeleton of DPA-XA-TRZ could not only enhance intramolecular electronic coupling, but also reduce steric hindrance and shorten intermolecular distance to enhance inter-CT process. A maximum external quantum efficiency (EQE max) of 21.9 % is achieved for the OLED device based on DPA-XA-TRZ, which is 2.5 times higher than that of DPA-FR-TRZ (8.4 %). DPA-XA-TRZ can also be utilized as an assistant host to sensitize multiple resonance TADF emitter DMAc-BN, and an EQE max of 31.7 % is realized owing to its dual CT processes and high reverse intersystem crossing rate (k RISC), which is significantly superior to the conventional mCBP host and mCBP:PO-T2T exciplex cohost. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multiple CT channels and 3LE states contribute to the speedy k r and RISC processes. • High Θ and small FWHM are realized due to the rigid disk-like structure. • η r and η out above 30% are achieved owing to triplet exciton utilization and high Θ. • EQE above 10% was realized for the standard blue device based on BO3N. The efficiency of pure blue Organic light-emitting diodes (OLEDs) still needs to be improved, which is limited by the utilization of the forbidden transition triplet excitons and low light-out-coupling efficiency in devices. Herein, two blue emitters were developed through combining multiple diphenylamine (DPA) donors with an oxygen-bridged boron (DBA) or triphenyl triazine (TRZ) acceptor. Notably, a narrow-band deep blue emission with a peak of 423 nm and a Full-width at half-maximum (FWHM) of 34 nm is realized for the boron-based emitter in toluene solution. Thanks to their multiple Charge transfer (CT) channels and high orientated disk-like structure, high radiative transition rates (k r > 108 s−1) and high horizontal emitting dipole ratios (Θ > 80%) can be realized simultaneously. Meanwhile, the introduction of the peripheral DPA units can also provide multiple localized triplet (3LE) states for spin up-conversion of forbidden transition triplet excitons. Owing to the effective up-conversion of triplet excitons and high light-out-coupling efficiency, maximum external quantum efficiency of more than 10% is achieved for the boron emitter-based pure blue OLEDs with a Commission Internationale de l'Eclairage (CIE) coordinates of (0.14, 0.08). [ABSTRACT FROM AUTHOR]