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Nanoindentation has emerged as a pioneering technique for fabricating array structures at the nanoscale. This research incorporates molecular dynamics simulations to investigate the deformation mechanisms of materials influenced by structured indenters exhibiting diverse geometries. The primary objective of this study is to mitigate interference during the continuous indentation applied by the indenters, diminish the material's elastic recovery, and minimize the occurrence of defects. The simulation results unveil that plastic deformation of the workpiece induced by structured indenters manifests through the nucleation and slip of dislocations. The cylindrical indenter engenders the most pronounced residual indentation morphology, accompanied by substantial pile-up interference and an extensive range of dislocation expansion, surpassing that of other indenters. Conversely, pyramidal indenters exhibit minimal residual indentation morphology, albeit displaying considerable elastic recovery. A comprehensive evaluation that considers factors such as recovery after indentation, ease of processing, system stability, and material transfer against the indentation force is imperative for the determination of the ideally structured indenter. The meticulous analysis supports the efficacy of paraboloidal indenters possessing smaller taper angles in attaining consistent processing results, rendering them highly suitable for continuous indentation processing. The research content bears significant implications for advancing the application of structured indenters. [Display omitted] • The defect evolution mechanisms of the structured indentation processing were analyzed. • The plastic deformation mechanisms of structured indenters processing were analyzed. • The filling rates of characteristic gaps were presented and calculated for structured indenters. • The indentation recovery rate and stability of the structured indenter were calculated and analyzed. [ABSTRACT FROM AUTHOR]

In 2 S 3 -NiS co-decorated MoO 3 @MoS 2 (INS/MoO 3 @MoS 2) heterojunctions were prepared in nonthermal plasma via the in-situ sulfurization for enhancing the solar-light photocatalytic conversion of CO 2 into CH 4 and CO at 423 K. In contrast with hexagonal h-MoO 3 nanorods, CH 4 and CO yields were enhanced by h-MoO 3 @MoS 2 and In 2 S 3 /MoO 3 @MoS 2 , while the increased CH 4 yield and decreased CO yield were obtained by INS/MoO 3 @MoS 2 and NiS/MoO 3 @MoS 2. The optimal 3-INS/MoO 3 @MoS 2 with a nominal NiS-In 2 S 3 content of 5.0 wt% and a In/Ni molar ratio of 2:1 exhibited the best photoreduction activity of CO 2 , of which CH 4 and CO yields were 49.11 and 6.19 μmol g−1 h−1, respectively. It's ascribed to the tight interface for enhancing the visible-light absorption capacity and reinforcing the transfer and separation of charge carriers. S-rich sites and O vacancies were favorable for the adsorption and photoreduction of reactants on the bulks surface. The nonthermal plasma induced in-situ sulfurization was thus a promising route to fabricate metal sulfides-based heterojunctions. [Display omitted] • In 2 S 3 -NiS co-decorated MoO 3 @MoS 2 was obtained by nonthermal plasma. • INS/MoO 3 @MoS 2 exhibited the enhanced photoreduction capacity toward CO 2. • The obtained junction interface favored the transfer and separation of charge carriers. • CO 2 was efficiently reduced into CH 4 and CO under solar-light irradiation. [ABSTRACT FROM AUTHOR]

Photocatalysis is a promising route to convert solar light into chemical energy for H 2 evolution and pollutants degradation. Hence, Ni 2 P decorated ZnCr 2 O 4 (Ni 2 P/ZnCr 2 O 4) nanofibers were prepared for boosting solar-light induced water splitting and tetracycline hydrochloride (TCH) degradation. For comparison to ZnCr 2 O 4 nanofibers, Ni 2 P/ZnCr 2 O 4 composites exhibited the better photocatalytic activities for water splitting and TCH removal. Owing to the co-catalytic effect of Ni 2 P for the efficient photon capture, the charge carriers were rapidly separated and migrated at the interface between Ni 2 P and oxygen-defected ZnCr 2 O 4. H 2 evolution rate of optimal C–Ni 2 P/ZnCr 2 O 4 with a nominal Ni 2 P content of 9.0 wt% was 575.89 μmol g−1 h−1, and its apparent quantum yield at 420 nm was 15.25 %, while its H 2 evolution decreased from 2815.13 to 2602.51 μmol g−1 after fifth cycle. In addition, the removal efficiency of C–Ni 2 P/ZnCr 2 O 4 was 93.68 % within 90 min, and declined to 88.76 % after five cycles for solar-light driven degradation of 50 mg L−1 TCH solution. The deactivation of C–Ni 2 P/ZnCr 2 O 4 was due to the photo-corrosion for the change in valence states of compositions. [ABSTRACT FROM AUTHOR]

Abstract Sm 2 O 3 coated with N-doped carbon (Sm 2 O 3 @N-C) nanocomposites were synthesized for the visible light driven degradation of tetracycline and RhB. The photo-degradation efficiency of Sm 2 O 3 @N-C was better than that of Sm 2 O 3 , g-C 3 N 4 , and Sm 2 O 3 /g-C 3 N 4 for the RhB removal. The photocatalytic activity of Sm 2 O 3 @N-C increased and then decreased with an increase in N-doping content for the tetracycline removal. N-doped carbon played a crucial role on the enhanced photocatalytic activity and the stability of Sm 2 O 3 @N-C with a carbon shell of 5 nm. It's ascribed to the special interface between Sm 2 O 3 and N-doped carbon, enhancing visible light sorption, facilitating the charge transfer and restraining the recombination of charge carriers. Highlights • Sm 2 O 3 coated with N-doped carbon was synthesized by the hydrothermal route. • Heterojunction interface facilitated the separation of electron-hole pairs. • Sm 2 O 3 @N-C exhibited the advanced photocatalytic activity and stability. [ABSTRACT FROM AUTHOR]

Abstract Ag-decorated core-shell Sm 2 O 3 @TiO 2 (Ag-Sm@TiO 2) nanocomposites were synthesized for the photocatalytic degradation of rhodamine B (RhB) under visible light irradiation. Compared with core-shell Sm 2 O 3 @TiO 2 nanoparticles, the enhanced photocatalytic activity of Ag-Sm@TiO 2 under visible light region was attributed to the surface plasmonic resonance effect of metallic silver and the interface effect between Sm 2 O 3 and TiO 2 in Fenton reaction system. The heterojunction consisted metallic Ag0 nanoparticles, Sm 2 O 3 core, and TiO 2 shell was suitable for the separation of photoexcited electron-hole pairs and the suppression of charge carriers recombination. In addition, the •OH radical was the key active radicals for the photocatalytic degradation of RhB in visible light region. Removal efficiency of RhB over Ag-Sm@TiO 2 increased and then decreased with the increasing Ag amount, of which the 6-Ag-Sm@TiO 2 with metallic Ag0 nanoparticles of 6.0 wt% exhibited the best photocatalytic activity and slightly deactivated after five cycle times. Highlights • Ag-decorated core-shell Sm 2 O 3 @TiO 2 was prepared via photodeposition route. • 6-Ag-Sm@TiO 2 presented the excellent photocatalytic activity and stability. • Heterojunction interface facilitated the separation of electron-hole pairs. [ABSTRACT FROM AUTHOR]

Highlights • Acid leaching process was conducted. • The optimized leaching conditions were determined. • Encapsulation efficiency was defined to describe the filtrate loss. • Shrinking core model expressed by [(1-η)−1/3−1]+1/3ln (1-η)=kt was investigated. Abstract Acid leaching technology was introduced to leach out vanadium from calcification roasting converter vanadium slag. The effects of solid-to-liquid ratio, concentration of acid solution, reaction temperature, reaction time and particle size on leaching efficiency of vanadium were examined. A new defined parameter, encapsulation efficiency, was applied to describe the leachate loss in the filtration process. Results showed that the leaching efficiency of vanadium and encapsulation efficiency had opposite change trends. Under the optimal conditions (solid-to-liquid ratio of 50 g slag/200 mL acid solution, concentration of 0.25 mol/L H 2 SO 4 , reaction temperature of 323 K, reaction time of 60 min, particle size under 75 μm and stirring rate of 500 rpm), the leaching efficiency and encapsulation were 91% and 6%, respectively. The calcium sulphate formed during the leaching process would absorb on the surface of slag and block the pore channel between the particles, and it had negative effect on filtration process. The shrinking core model expressed by [(1-η)−1/3−1] +1/3ln (1-η) = kt was used to describe the leaching kinetics of vanadium in sulphur acid solutions. And the apparent activation energy of vanadium extraction was determined to be 12.45 kJ/mol, which indicated that the leaching process was controlled mainly diffusion of solution through surface layer. [ABSTRACT FROM AUTHOR]

CeO 2 -coated α-Fe 2 O 3 nanoparticles (α-Fe 2 O 3 @CeO 2 ) with the enhanced photocatalytic activity were synthesized by a hydrothermal route and performed for the visible light driven photo-degradation of methylene blue (MB). The photocatalytic activity of α-Fe 2 O 3 @CeO 2 is greatly affected by the thickness of CeO 2 shell under the same conditions. The core-shell structured α-Fe 2 O 3 @CeO 2 sample exhibited a narrower band gap energy in comparison to the pure α-Fe 2 O 3 and CeO 2 bulks, leading to the excellent photocatalytic activity and stability for the degradation of MB under visible light irradiation after five cycle times. The core-shell structured α-Fe 2 O 3 @CeO 2 sample presented higher degradation activity than that of the supported 8-Fe/CeO 2 bulks with optimized α-Fe 2 O 3 loading of 8%. It can be ascribed to the Ce 4+ /Ce 3+ redox couple and the heterojunction interfaces of core-shell structured α-Fe 2 O 3 @CeO 2 sample, which can promote the electrons transfer and restrain the photoexcited electron-hole recombination, leading to the excellent degradation activity under visible light irradiation. [ABSTRACT FROM AUTHOR]

Cu x Zn 1-x S nanodisks with varying Cu/Zn molar ratio were synthesized for the photodegradation of Rhodamine B (RhB) using a one-pot hydrothermal route. The Cu x Zn 1-x S nanodisks were formed through the self–assembly of ZnS and CuS nanoparticles assisted with surfactant in hydrothermal system. The optimum photodegradation efficiency over Cu 0.33 Zn 0.67 S with the Cu/Zn molar ratio of 1:2 was higher than that of ZnS and CuS for the H 2 O 2 -assisted photodegradation of RhB under visible light irradiation. The stability of Cu 0.33 Zn 0.67 S was slightly deactivated after five cycle times. The ESR results suggested that abundant O 2 − radicals and less OH radicals participated in the visible light driven photocatalytic reaction of Cu 0.33 Zn 0.67 S. [ABSTRACT FROM AUTHOR]

CeO 2 with X-architecture was synthesized using the hydrothermal route assisted by polyvinyl pyrrolidone, and employed to investigate the degradation of methylene blue under UV-light irradiation. The as-obtained CeO 2 sample exhibited higher photocatalytic activity than traditional CeO 2 sample prepared by precipitation route due to its irregular X-architecture shape with clear boundary and micro/mesopore surface structure. The novel X-architecture shape of CeO 2 facilitates the efficient photo-generated charge transfer and separation under UV-light irradiation, leading to the superior stability for the photo-degradation of methylene blue. [ABSTRACT FROM AUTHOR]