Weijia Zhou

Bio: Weijia Zhou is an academic researcher from Shandong University. The author has contributed to research in topics: Overpotential & Nanorod. The author has an hindex of 4, co-authored 5 publications receiving 1274 citations. Previous affiliations of Weijia Zhou include Nanyang Technological University & South China University of Technology.

Ni3S2 nanorods/Ni foam composite electrode with low overpotential for electrocatalytic oxygen evolution

Abstract: A Ni3S2 nanorods/Ni foam composite electrode is prepared as a high-performance catalyst for the oxygen evolution reaction (OER), which exhibits excellent OER activity with a small overpotential of ∼157 mV based on the onset of catalytic current.

One-step synthesis of Ni3S2 nanorod@Ni(OH)2nanosheet core–shell nanostructures on a three-dimensional graphene network for high-performance supercapacitors

Abstract: A three-dimensional graphene network (3DGN) grown on nickel foam is an excellent template for the synthesis of graphene-based composite electrodes for use in supercapacitors. Ni(OH)2nanosheets coated onto single-crystal Ni3S2nanorods grown on the surface of the 3DGN (referred to as the Ni3S2@Ni(OH)2/3DGN) are synthesized using a one-step hydrothermal reaction. SEM, TEM, XRD and Raman spectroscopy are used to investigate the morphological and structural evolution of the Ni3S2@Ni(OH)2/3DGN. Detailed electrochemical characterization shows that the Ni3S2@Ni(OH)2/3DGN exhibits high specific capacitance (1277 F g−1 at 2 mV s−1 and 1037.5 F g−1 at 5.1 A g−1) and areal capacitance (4.7 F cm−2 at 2 mV s−1 and 3.85 F cm−2 at 19.1 mA cm−2) with good cycling performance (99.1% capacitance retention after 2000 cycles).

Composite catalytic electrode for producing oxygen by electrolyzing water, and preparation method and application thereof

Abstract: The invention discloses a composite catalytic electrode for producing oxygen by electrolyzing water, and a preparation method and application thereof. The electrode expression is Ni(OH)2/Ni3S2/Ni, wherein a Ni(OH)2 lamina is used as an outer layer coating layer, Ni3S2 nanoparticles are used as an active substance, and Ni foam is used as a conducting substrate. The preparation method comprises the following steps: carrying out ultrasonic cleaning on a metal nickel source sequentially with deionized water, alcohol and acetone; impregnating the pretreated metal nickel source in a sulfur source water solution, adding into a high-pressure autoclave, and carrying out hydrothermal reaction at 140-200 DEG C for 1-8 hours; and cooling, taking out the sulfurized metal nickel, rinsing with deionized water, and carrying out vacuum drying. The composite electrode for electrolyzing water has ultralow water electrolysis overpotential and high current density, obviously reduces the electric power consumption, and thus, has important application in the field of water electrolysis. Meanwhile, the composite electrode synthesis method is simple, has the advantage of low cost for raw materials and synthesis, and is suitable for application in water electrolysis industry.

Construction of Strong Alkaline Hydrothermal Environment for Synthesis of Copper Telluride Nanowires.

Abstract: Cu2-xTe nanowires are hydrothermally synthesized from a 6 M KOH aqueous solution of CuCl2, Te powder, and hydrazine hydrate as reducing agent (autoclave, 200 °C, 24 h), followed by annealing at 250 °C for 4 h in N2.

Recent Advances in Ultrathin Two-Dimensional Nanomaterials

Abstract: Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially in the fields of condensed matter physics, material science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, and optical properties, as well as their various potential applications, in this Review, we summarize the state-of-art progress on the ultrathin 2D nanomaterials with a particular emphasis on their recent advances. First, we introduce the unique advances on ultrathin 2D nanomaterials, followed by the description of their composition and crystal structures. The assortments of their synthetic methods are then summarized, including insights on their advantages and limitations, alongside some recommendations on suitable characterization techniques. We also discuss in detail the utilization of these ultrathin 2D nanomaterials for wide ranges of potential applications among the electronics/optoelectronics, electrocat...

Recent Progress in Cobalt‐Based Heterogeneous Catalysts for Electrochemical Water Splitting

Abstract: Water electrolysis is considered as the most promising technology for hydrogen production. Much research has been devoted to developing efficient electrocatalysts for hydrogen production via the hydrogen evolution reaction (HER) and oxygen production via the oxygen evolution reaction (OER). The optimum electrocatalysts can drive down the energy costs needed for water splitting via lowering the overpotential. A number of cobalt (Co)-based materials have been developed over past years as non-noble-metal heterogeneous electrocatalysts for HER and OER. Recent progress in this field is summarized here, especially highlighting several important bifunctional catalysts. Various approaches to improve or optimize the electrocatalysts are introduced. Finally, the current existing challenges and the future working directions for enhancing the performance of Co-implicated electrocatalysts are proposed.

Recent Trends and Perspectives in Electrochemical Water Splitting with an Emphasis on Sulfide, Selenide, and Phosphide Catalysts of Fe, Co, and Ni: A Review

Abstract: Increasing demand for finding eco-friendly and everlasting energy sources is now totally depending on fuel cell technology. Though it is an eco-friendly way of producing energy for the urgent requirements, it needs to be improved to make it cheaper and more eco-friendly. Although there are several types of fuel cells, the hydrogen (H2) and oxygen (O2) fuel cell is the one with zero carbon emission and water as the only byproduct. However, supplying fuels in the purest form (at least the H2) is essential to ensure higher life cycles and less decay in cell efficiency. The current large-scale H2 production is largely dependent on steam reforming of fossil fuels, which generates CO2 along with H2 and the source of which is going to be depleted. As an alternate, electrolysis of water has been given greater attention than the steam reforming. The reasons are as follows: the very high purity of the H2 produced, the abundant source, no need for high-temperature, high-pressure reactors, and so on. In earlier days,...

High-index faceted Ni3S2 nanosheet arrays as highly active and ultrastable electrocatalysts for water splitting.

Abstract: Elaborate design of highly active and stable catalysts from Earth-abundant elements has great potential to produce materials that can replace the noble-metal-based catalysts commonly used in a range of useful (electro)chemical processes. Here we report, for the first time, a synthetic method that leads to in situ growth of {210} high-index faceted Ni3S2 nanosheet arrays on nickel foam (NF). We show that the resulting material, denoted Ni3S2/NF, can serve as a highly active, binder-free, bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Ni3S2/NF is found to give ∼100% Faradaic yield toward both HER and OER and to show remarkable catalytic stability (for >200 h). Experimental results and theoretical calculations indicate that Ni3S2/NF’s excellent catalytic activity is mainly due to the synergistic catalytic effects produced in it by its nanosheet arrays and exposed {210} high-index facets.

NiSe Nanowire Film Supported on Nickel Foam: An Efficient and Stable 3D Bifunctional Electrode for Full Water Splitting

Abstract: Active and stable electrocatalysts made from earth-abundant elements are key to water splitting for hydrogen production through electrolysis. The growth of NiSe nanowire film on nickel foam (NiSe/NF) insitu by hydrothermal treatment of NF using NaHSe as Se source is presented. When used as a 3D oxygen evolution electrode, the NiSe/NF exhibits high activity with an overpotential of 270mV required to achieve 20mAcm(-2) and strong durability in 1.0M KOH, and the NiOOH species formed at the NiSe surface serves as the actual catalytic site. The system is also highly efficient for catalyzing the hydrogen evolution reaction in basic media. This bifunctional electrode enables a high-performance alkaline water electrolyzer with 10mAcm(-2) at a cell voltage of 1.63V.