Publications

Defective and perfect sites naturally exist within electronic semiconductors, and considerable efforts to reduce defects to improve the performance of electronic devices, especially in hybrid organic-inorganic perovskites (ABX₃ ), are undertaken. Herein, foldable hole-transporting materials (HTMs) are developed, and they extend the wavefunctions of A-site cations of perovskite, which, as hybridized electronic states, link the trap states (defective site) and valence band edge (perfect site) between the naturally defective and perfect sites of the perovskite surface, finally converting the discrete trap states of the perovskite as the continuous valence band to reduce trap recombination. Tailoring the foldability of the HTMs tunes the wavefunctions between defective and perfect surface sites, allowing the power conversion efficiency of a small cell to reach 23.22% and that of a mini-module (6.5 × 7 cm, active area = 30.24 cm² ) to reach as high as 21.71% with a fill factor of 81%, the highest value reported for non-spiro-OMeTAD-based perovskite solar modules.

Abstract The industrial artificial fixation of atmospheric N 2 to NH 3 is carried out using the Haber–Bosch process that is not only energy‐intensive but emits large amounts of greenhouse gas. Electrochemical reduction offers an environmentally benign and sustainable alternative for NH 3 synthesis. Although Mo‐dependent nitrogenases and molecular complexes effectively catalyze the N 2 fixation at ambient conditions, the development of a Mo‐based nanocatalyst for highly performance electrochemical N 2 fixation still remains a key challenge. Here, greatly boosted electrocatalytic N 2 reduction to NH 3 with excellent selectivity by defect‐rich MoS 2 nanoflowers is reported. In 0.1 m Na 2 SO 4 , this catalyst attains a high Faradic efficiency of 8.34% and a high NH 3 yield of 29.28 µg h −1 mg −1 cat. at − 0.40 V versus reversible hydrogen electrode, much larger than those of defect‐free counterpart (2.18% and 13.41 µg h −1 mg −1 cat. ), with strong electrochemical stability. Density functional theory calculations show that the potential determining step has a lower energy barrier (0.60 eV) for defect‐rich catalyst than that of defect‐free one (0.68 eV).

Chitosan is a pseudo-neutral cationic polymer which is formed by the de-acetylation of chitin polymer. Various patent on chitosan and chitosan-nanocomposite were taken into account related to wastewater purification. We have found that chitosan and chitosan-nanocomposite are used for the removal of viruses, bacteria, cryptosporidium oocysts and giardia cysts, soluble and insoluble organic pollutants, poly aromatic hydrocarbons and heavy metals from wastewater. In this study, we also found that chitosan and chitosan-nanocomposite are selected for the removal of transition metals.

A Pt|Nafion|Pt–Cu assembly can exhibit its best reduction reaction efficiency in the absence of any supporting electrolytes. Adsorption of supporting electrolytes decreases efficiency by registering an increase of charge transfer resistance.

Dimethine cyanine dye (PTZIS) based on phenothiazine as the core donor and indolium salt as the acceptor has been synthesized and fully characterized. UV-Vis absorption and fluorescence properties of PTZIS were studied in different solvents. Absorption spectra revealed a large bathochromic shift of the intramolecular charge transfer (ICT) absorption band of PTZIS compared with those in the non-halogenated solvents. Also, the optical data of PTZIS showed a large Stokes shift compared with those in the non-halogenated solvents, indicating a great influence on the geometry of the emissive excited state. The nonlinear optical properties of PTZIS in ethanol solution at different concentrations and different laser powers have been studied using the Z-scan technique with a continuous wave (cw) argon ion laser at 514.5 nm. The closed aperture Z-scan data was used to estimate the nonlinear refractive index n2, while the open aperture scan provided the nonlinear absorption coefficient β. The values obtained are relatively very high and vary linearly with concentration.

The Co₂N nanowire film on a Ti mesh (Co₂N/TM) and Co-phosphate nanowire film on a Ti mesh (Co–Pi/TM) act as complementary water-splitting electrocatalysts with strong durability in 1.0 M PBS, affording 10 mA cm⁻² at 1.78 V.

In this communication, we develop a facile, one-step strategy towards the rapid synthesis of ZnO nanoparticle-decorated reduced graphene oxide (rGO–ZnO) composites by directly immersing Zn plate in a GO solution containing ammonia with the aid of ultrasonication at room temperature. The rGO–ZnO composites obtained have applications in photocurrent generation in the visible spectral region of white light using zinc porphyrin (ZnP) as a photosensitizer.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

In spite of recent advances in the synthesis of transition metal phosphide nanostructures, the simple fabrication of hierarchical arrays with more accessible active sites still remains a great challenge. In this Communication, we report a space-confined phosphidation strategy toward developing hierarchical CoP nanosheet@microwire arrays on nickel foam (CoP NS@MW/NF) using a Co(H2PO4)2·2H3PO4 microwire array as the precursor. The thermally stable nature of the anion in the precursor is key to hierarchical nanostructure formation. When used as a 3D electrode for water oxidation electrocatalysis, such CoP NS@MW/NF needs an overpotential as low as 296 mV to drive a geometrical catalytic current density of 100 mA cm-2 in 1.0 M KOH, outperforming all reported Co phosphide catalysts in alkaline media. This catalyst also shows superior long-term electrochemical durability, maintaining its activity for at least 65 h. This study offers us a general method for facile preparation of hierarchical arrays for applications.

Abstract Under visible light irradiation, the nanoparticles cause formation of a Cu(I) catalyst which initiates the cycloaddition process.

In this paper, a stable aqueous dispersion of graphene nanosheets (GNs) has been prepared by chemical reduction of graphene oxide (GO) with hydrazine hydrate in the presence of poly [(2-ethyldimethylammonioethyl methacrylate ethyl sulfate)-co-(1-vinylpyrrolidone)] (PQ11). Taking advantages of the fact that PQ11 is a positively charged polymer exhibiting reducing ability, we further demonstrated the subsequent decoration of GN with gold nanoparticals (AuNPs) by in-situ chemical reduction of HAuCl4. It was found that such nanocomposites exhibit good catalytic activity toward 4-nitrophenol (4-NP) reduction and the GN supports also enhance the catalytic activity via a synergistic effect.