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• 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]

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]