The recent developments of nanostructured WO3 thin films synthesized through the electrochemical route of electrochemical anodization and cathodic electrodeposition for the application in photoelectrochemical (PEC) water splitting are reviewed. The key fundamental reaction mechanisms of electrochemical anodization and cathodic electrodeposition methods for synthesizing nanostructured WO3 thin films are explained. In addition, the effects of metal oxide precursors, electrode substrates, applied potentials and current densities, and annealing temperatures on size, composition, and thickness of the electrochemically synthesized nanostructured WO3 thin films are elucidated in detail. Finally, a summary is given for the general evaluation practices used to calculate the energy conversion efficiency of nanostructured WO3 thin films and a recommendation is provided to standardize the presentation of research results in the field to allow for easy comparison of reported PEC efficiencies in the near future.

The low-temperature magnetic and transport properties of La2/3Sr1/3MnO3 nanoparticles have been investigated. It is found that a surface spin-glass behavior exists in La2/3Sr1/3MnO3 nanoparticles, which undergo a magnetic transition to a frozen state below 45 K. The low-temperature surface spin-glass behavior exists even at the highest field used (H=50 kOe). Moreover, the spin-glass-like transition disappears for particles above 50 nm. In addition, the suppressed low-field magnetoconductivity (LFMC) observed at low temperature for nanosized La2/3Sr1/3MnO3 is obviously lower than the expected upper limit of LFMC, 1/3, for polycrystalline manganites, which is proposed to arise from the higher-order tunneling through the insulating spin-glass-like surface layers.

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In this work, room-temperature operated ultrasensitive solution-processed perovskite photodetectors (PDs) with near infrared (NIR) photoresponse is reported. In order to enable perovskite PDs possessing extended NIR photoresponse, novel n-type low bandgap conjugated polymer, poly [(N,N'-bis(NDI-DPP), which has strong absorption in the NIR region, is developed and then employed in perovskite PDs. By formation of type II band alignment between NDI-DPP with single wall carbon nanotubes (SWCNTs), the NIR absorption of NDI-DPP has been exploited, which contributes to the NIR photoresponse for the perovskite PDs, where perovskite is incorporated with NDI-DPP and SWCNTs as well. In addition, SWCNTs incorporated with perovskite active layer can offer the percolation pathways for high charge carrier mobility, which tremendously boosts the charge transfer in the photoactive layer, and consequently improves the photocurrent in the visible region. As a result, the perovskite PDs exhibits the responsivities of ~400 mA/W and ~150 mA/W and the detectivities of over 6×10 12 Jones (1 Jones =1 cmHz 1/2 W -1 ) and over 2×10 12 Jones in the visible and NIR regions, respectively.Our work reports the development of perovskite PDs with NIR photoresponse, which is terrifically beneficial for the practical applications of perovskite PDs.

Among the 3D organic-inorganic hybrid perovskite (OIHP), mixed formamidinium and methylammonium cations lead iodide is one of the most promising for solar cell application. After optimizing the use of methylammonium chloride (MACl) additive for the preparation of compact, high quality and large crystal grain layers made of pure α-phase perovskite with FA0.94MA0.06PbI3 composition, the treatment of the perovskite surface by a 2-Phenylethylamonium iodide (PEAI) solution has been implemented. This treatment, without any thermal annealing, leads notably to the spontaneous formation of a crystallized (PEA)2PbI4 2Dperovskite nanolayer at the film surface due to partial organic cation dissolution. This buffer layer

As a promising microwave absorber filler, molybdenum disulfide (MoS 2 ), because of the unique structure, high electrical conductivity, and polarization effect, is receiving more and more interest. Developing MoS 2 -based composites with specific structure and morphology is a hot top in the field of microwave absorbers, because of its strong multiple scattering and reflecting for microwaves as well as its unique interfacial characteristics. Now, with a facile solvothermal method, a novel core−shell CoFe 2 O 4 @1T/2H-MoS 2 composite is synthesized, where the CoFe 2 O 4 nanospheres are entirely embedded in a special three-dimensional (3D) nest-like 1T/2H phase MoS 2 . Notably, in comparison with superparamagnetic CoFe 2 O 4 nanospheres, the coercivities of as-synthesized CoFe 2 O 4 @1T/2H-MoS 2 composites greatly increase. Here, 1T/2H-MoS 2 exhibits ferromagnetism superimposed onto large diamagnetism. It is noted that, by adjusting the content of 1T/2H-phase MoS 2 , the microwave absorption performance of as-synthesized composites can be effectively tuned. The combination of 1T/2H-MoS 2 with CoFe 2 O 4 helps to adjust the permittivity and optimize the impedance matching of the composites. Impressively, a minimum reflection loss (RL min ) of −68.5 dB for the as-synthesized composites with a thickness of 1.81 mm is gained at 13.2 GHz; meanwhile, a broad effective bandwidth of 4.56 GHz ranged from 13.2 to 17.76 GHz is achieved at 1.6 mm. Further, the overall effective bandwidth (RL < −10 dB) is obtained up to 14.5 GHz from 3.5 to 18.0 GHz, covering more than 90% of the measured frequency range. The high microwave absorption performance is ascribed to the special structure design with the core of magnetic CoFe 2 O 4 nanospheres and the shell of dielectric nest-like 1T/2H-MoS 2 as well as their appropriate impedance matching. From the perspective of basic research and practical microwave application, this study provides another feasible and effective pathway to design novel MoS 2 -based magnetic/dielectric microwave absorbers.