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This paper adopts a contrastive experimental method to design and prepare reed fiber concrete. It discusses the influence of reed fiber content (2%), fiber length (1.5 cm for short reed fiber and 3 cm for long reed fiber), and moisture content (0% for dry fiber and 85% for wet fiber) on the mechanical properties of concrete, and compares it with the reference concrete without reed fiber. The experiment obtained the flexural and compressive strength of reed concrete, and analyzed the apparent mechanism of concrete specimens after failure. The experimental results show that the addition of reed fiber enhances the mechanical properties of concrete, the compressive strength of concrete increases by 1.13 MPa compared with the reference concrete, and the flexural strength increases by 2.32 MPa. The flexural performance of reed fiber reinforced concrete with 3 cm dry fiber and 0% moisture content is the highest, reaching 3.5 MPa; the compressive performance of reed fiber reinforced concrete with 85% moisture content and short reed fiber is the highest, reaching 2.69 MPa. This paper shows that adding 2% of reed fiber to concrete is feasible, and adding 1.5 cm, 85% moisture content wet reed fiber can better promote the mechanical properties of reed fiber concrete.

Precise design and synthesis of sub-nano scale catalysts with controllable electronic and geometric structures are pivotal for enhancing the hydrogen evolution reaction (HER) performance of molybdenum sulfide (MoS2) and unraveling its structure-activity relationship. By leveraging transition molybdenum polysulfide clusters as functional units for multi-level ordering, we successfully designed and synthesized MoSx nanowire networks derived from [Mo3S13]2− clusters via evaporation-induced self-assembly, which exhibit enhanced HER activity attributed to a high density of active sites and dynamic evolution behavior under cathodic potentials. MoSx nanowire networks electrode yields a current density of 100 mA·cm−2 at 142 mV in 0.5 M H2SO4. This work provides an attractive prospect for optimizing catalysts at the sub-nano scale and offers insights into a strategy for designing catalysts in various gas evolution reactions. [ABSTRACT FROM AUTHOR]

The transition metal chalcogenides represented by MoS2 are the ideal choice for non-precious metal-based hydrogen evolution catalysts. However, whether in acidic or alkaline environments, the catalytic activity of pure MoS2 is still difficult to compete with Pt. Recent studies have shown that the electronic structure of materials can be adjusted by constructing lattice-matched heterojunctions, thus optimizing the adsorption free energy of intermediates in the catalytic hydrogen production process of materials, so as to effectively improve the electrocatalytic hydrogen production activity of catalysts. However, it is still a great challenge to prepare heterojunctions with lattice-matched structures as efficient electrocatalytic hydrogen production catalysts. Herein, we developed a one-step hydrothermal method to construct Ni-MoS2@NiS2@Ni3S2 (Ni-MoS2 on behalf of Ni doping MoS2) electrocatalyst with multiple heterogeneous interfaces which possesses rich catalytic reaction sites. The Ni-MoS2@NiS2@Ni3S2 electrocatalyst produced an extremely low overpotential of 69.4 mV with 10 mA·cm−2 current density for hydrogen evolution reaction (HER) in 1.0 M KOH. This work provides valuable enlightenment for exploring the mechanism of HER enhancement to optimize the surface electronic structure of MoS2, and provides an effective idea for constructing rare metal catalysts in HER and other fields. [ABSTRACT FROM AUTHOR]