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The WUSCHEL-related homeobox (WOX) family members are plant-specific transcriptional factors, which function in meristem maintenance, embryogenesis, lateral organ development, as well as abiotic stress tolerance. In this study, 14 MsWOX transcription factors were identified and comprehensively analyzed in the cultivated alfalfa cv. Zhongmu No.1. Overall, 14 putative MsWOX members containing conserved structural regions were clustered into three clades according to phylogenetic analysis. Specific expression patterns of MsWOXs in different tissues at different levels indicated that the MsWOX genes play various roles in alfalfa. MsWUS, MsWOX3, MsWOX9, and MsWOX13-1 from the three subclades were localized in the nucleus, among which, MsWUS and MsWOX13-1 exhibited strong self-activations in yeast. In addition, various cis-acting elements related to hormone responses, plant growth, and stress responses were identified in the 3.0 kb promoter regions of MsWOXs. Expression detection of separated shoots and roots under hormones including auxin, cytokinin, GA, and ABA, as well as drought and cold stresses, showed that MsWOX genes respond to different hormones and abiotic stress treatments. Furthermore, transcript abundance of MsWOX3, and MsWOX13-2 were significantly increased after rhizobia inoculation. This study presented comprehensive data on MsWOX transcription factors and provided valuable insights into further studies of their roles in developmental processes and abiotic stress responses in alfalfa. [ABSTRACT FROM AUTHOR]

The composite photocatalysts composed of BiPbO 2 Cl and reduced graphene oxide (rGO) were synthesized by a one-step hydrothermal method. The UV–vis absorbance spectra results show that the BiPbO 2 Cl nanosheet absorbs more visible light when it is combined with graphene. The Raman spectra results indicate that the D and G bands are not visible from the Raman spectra of BiPbO 2 Cl, and the peak strength of two bands is increased with the increase of graphene content. The obtained 2 wt% rGO/BiPbO 2 Cl nanosheet composites exhibit higher photocatalytic activity, which is 5.7 times compared with that of BiPbO 2 Cl nanosheets. The improved photocatalytic activity of the rGO/BiPbO 2 Cl composites is ascribed to effective charge transfer due to graphene. [ABSTRACT FROM AUTHOR]

The electrocatalytic hydrogen evolution activity of transition metal sulfide heterojunctions are significantly increased when compared with that of a single component, but the mechanism behind the performance enhancement and the preparation of catalysts with specific morphologies still need to be explored. Here, we prepared a Co9S8/MoS2 heterojunction with microsphere morphology consisting of thin nanosheets using a facile two-step method. There is electron transfer between the Co9S8 and MoS2 of the heterojunction, thus realizing the redistribution of charge. After the formation of the heterojunction, the density of states near the Fermi surface increases, the d-band center of the transition metal moves downward, and the adsorption of both water molecules and hydrogen by the catalyst are optimized. As a result, the overpotential of Co9S8/MoS2 is superior to that of most relevant electrocatalysts reported in the literature. This work provides insight into the synergistic mechanisms of heterojunctions and their morphological regulation. [ABSTRACT FROM AUTHOR]

• MoS 2 /BiVO 4 heterojunction degrade RhB solution quickly without any addition agent. • Electrons in CB of MoS 2 and holes in VB of BiVO 4 promote redox ability. • MoS 2 /BiVO 4 heterojunction drive photocatalytic discoloration of RhB. Heterojunction photocatalysts can accelerate photo-excited electron-hole separation in the photocatalytic application. Herein, one BiVO 4 @MoS 2 core-shell heterojunction was synthesized via growing MoS 2 nanosheets on electrospinning-fabricated BiVO 4 nanorods by solvothermal technique. The MoS 2 /BiVO 4 heterojunction can completely degrade RhB solution within 20 min without any additional agent. According to the S-scheme heterojunction principle, the electron transfer process retains the powerful electrons in CB of MoS 2 and powerful holes in VB of BiVO 4 , and then promotes the excellent redox ability and strong driving force for photocatalytic discoloration of RhB. [ABSTRACT FROM AUTHOR]

• A series of BiVO 4 samples composited with NiSe 2 nanosheets were prepared through a facile solvothermal method. • The photocatalytic degradation rate of RhB of the optimized sample reaches 11 times higher than that of pure BiVO 4. • The Schottky junction derived from the discrepancy of work function accelerates the separation of photogenerated carriers. • The interaction at the interface reduces the band gap of BiVO 4. The rapid recombination of photogenerated carriers limits the photocatalytic activity of BiVO 4. Here, we grew NiSe 2 nanosheets on the surface of BiVO 4 through a facile solvothermal method to construct a Schottky junction. Due to the discrepancy of work function, electrons at the interface are transferred from BiVO 4 to NiSe 2 , thereby forming a built-in electric field. In virtue of the built-in electric field and the good conductivity of NiSe 2 , the photo-generated carriers can be quickly separated and transferred. In addition, the interaction at the interface reduces the band gap of BiVO 4 , which increases the absorption of visible light. These above benefits improve the photocatalytic performance. The photocatalytic reaction under visible light shows that the degradation rate of RhB for 9 mol% NiSe 2 composited BiVO 4 increases by 11 times compared with pure BiVO 4. The simplicity of the preparation method and the significantly improved performance show the enormous potential of NiSe 2 to be coupled with other semiconductor photocatalysts to improve their catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract Exploiting effective photocatalytic materials especially co-catalysts is an effective solution to enhance solar hydrogen generation. In this work, we firstly introduce FeSe as highly efficient co-catalyst on the surface of CdS nanoparticles for photocatalytic H 2 evolution under visible light irradiation. The optimized 2 wt% FeSe/CdS composite showed the highest photocatalytic H 2 evolution activity of 204.4 μL/h with an apparent quantum efficiency of 6.71% at 420 nm, which is about 7 times higher than that of pure CdS nanoparticles. More importantly, 2 wt% FeSe/CdS composite also exhibits higher photocatalytic activity than that of 2 wt% Pt/CdS composite under the same condition. The higher photocatalytic H 2 evolution property of FeSe/CdS composite is due to that the photo-generated electrons can be driven by the build-in field and transferred to the surface of FeSe causing electron-hole separation. This work may provide the potential applications of FeSe as a co-catalyst for photocatalytic H 2 evolution. Graphical abstract Image 1 Highlights • FeSe/CdS composites have been successfully synthesized. • The photocatalytic H 2 evolution activity of FeSe/CdS composite is about 7 times of pure CdS nanoparticles. • The photo-generated electrons can be driven by build-in field and transferred to the surface of FeSe. [ABSTRACT FROM AUTHOR]

The key process in diamond-like carbon (DLC) film deposition is the formation of sp 3 -C hybridized bond, which is believed to significantly link to the ionization degrees of the carbon atoms. Ne has a high ionization energy and can facilitate the ionization degree of sputtered carbon. In this paper, Ne and Ar gas mixture was used as the sputtering gas to prepare DLC film by using a pulsed-magnetron sputter. The influences of the Ne fraction in the sputtering gas mixture on the growth character, carbon bond structure, residual stress and mechanical properties of the as-deposited DLC films were studied carefully by using scanning electron microscope, Raman spectroscopy, stress tester and nano-indentation, respectively. The results reveal that the introduction of Ne in sputtering gas mixture can induce the structure densification of the coatings, and significantly increase the sp 3 fraction of the DLC films. However, it was found that the sp 3 fraction of the films increased little as the Ne fraction exceeded 25%. This phenomenon might be attributed to the reduction of the electron density of the plasma due to the increase of the Ne fraction in the sputtering gas mixture. The residual stress of the DLC films was believed to depend on the sp 3 fraction of the films, and thus exhibited a similar changing trend to sp 3 fraction as a function of Ne fraction. However, the hardness and elastic modulus of the films increased continuously as the Ne fraction increased. The structure densification and the increase of the sp 3 fraction caused by the addition of Ne may be the main factors contributed to the increase of the hardness and elastic modulus of the films. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution is considered as a sustainable and economical scheme to meet the energy demand and solve the environmental pollution. Herein, we developed a sandwich sintering strategy to improve the production yield and uniformity of g-C 3 N 4 inverse opal (CN IO) nanostructure via SiO 2 colloidal crystal template. Based on the highly ordered CN IO nanostructure, novel photocatalysts of silver-modified CN IO (Ag–CN IO) nanocomposites were presented. The formation mechanism, morphology, microstructure, element content and distribution, optical and electrochemical properties were investigated. The photocatalytic performances were evaluated by H 2 evolution under visible light irradiating. Also, the effects of Ag content and morphology of the nanostructures on the photocatalytic performances were studied. The results show that the as-developed Ag–CN IO exhibits the best H 2 evolution performance among all the tested samples. The enhanced photocatalytic performance of the Ag–CN IO is mainly attributed to the Ag nanoparticles and IO structure, which can synergistically improve the light absorption and charge transfer as well as the surface kinetics. The photocatalytic mechanism of the Ag–CN IO was also proposed. [Display omitted] • A sandwich sintering strategy is developed to fabricate g-C 3 N 4 inverse opal (CN IO). • We present a novel photocatalyst of Ag-modified CN IO (Ag–CN IO). • Ag–CN IO exhibits improved visible light absorption and charge transfer. • Ag–CN IO shows boosted photocatalytic hydrogen evolution. • The boosted activity is due to the synergistic effects of CN IO and Ag. [ABSTRACT FROM AUTHOR]

Lamellar MoS 2 has attracted widespread attention as a potential electrocatalytic HER (Hydrogen evolution reaction) catalyst. However, it is difficult to further improve its catalytic activity due to two major drawbacks: the limited number of active sites and its poor conductivity. Here, we adopt a one-step method utilizing an ultrafast pulsed laser treatment to produce multiple decorations on lamellar MoS 2 , where nanocrystallization and amorphization of lamellar MoS 2 are achieved simultaneously, along with an additional characteristic of atomic steps. Due to this special microstructure, laser-treated MoS 2 exhibits excellent electrocatalytic performance with a low overpotential and a small Tafel slope (217 mV @ 10 mA cm−2 and 74.5 mV dec−1, respectively), which is superior to that of untreated lamellar MoS 2 (461 mV @ 10 mA cm−2 and 142.6 mV dec−1, respectively). The MoS 2 prepared in this way has a high catalytic activity and a high stability, which indicates potential for electrocatalysis applications. • We proposed a one-step method using ultrafast pulsed laser treatment to enhance the HER performance of lamellar MoS 2. • We prepared ultra-small MoS 2 nanoparticles, amorphization, and atomic steps in situ on lamellar MoS 2. • The performance of treated MoS 2 is far superior to that of MoS 2 before laser treatment. [ABSTRACT FROM AUTHOR]

• The correlation between structures and the T c in FeSe-family is presented for the first time. • The distorted FeSe 4 tetrahedron plays an important role in understanding the superconductivity. • The electronic correlation and FS nesting between electron pockets are associated with distorted FeSe 4 tetrahedron. • The crystal structure of N 0.81(1) D 3.24(2) Fe 2 Se 2 is determined by neutron and x-ray powder diffraction. We demonstrate that unique cation, ND 4 (1−δ)+, exists between FeSe layers and induces a large distortion of the FeSe 4 tetrahedron in N 0.81(1) D 3.24(2) Fe 2 Se 2 by neutron and X-ray powder diffraction. The electronic correlations of the Fe 3d electrons and Fe d xy , d yz and d xz band widths could be tuned by changing the FeSe 4 tetrahedron distortion, revealing the importance of lattice distortion to the superconductivity of FeSe-based intercalates. [ABSTRACT FROM AUTHOR]