Integrated Hierarchical Cobalt Sulfide/Nickel Selenide Hybrid Nanosheets as an Efficient Three-dimensional Electrode for Electrochemical and Photoelectrochemical Water Splitting.

Title Integrated Hierarchical Cobalt Sulfide/Nickel Selenide Hybrid Nanosheets as an Efficient Three-dimensional Electrode for Electrochemical and Photoelectrochemical Water Splitting.
Authors Y. Hou; M. Qiu; G. Nam; M.Gyu Kim; T. Zhang; K. Liu; X. Zhuang; J. Cho; C. Yuan; X. Feng
Journal Nano Lett
DOI 10.1021/acs.nanolett.7b01030
Abstract

Developing highly active electrocatalysts for photoelectrochemical water splitting is critical to bring solar/electrical-to-hydrogen energy conversion processes into reality. Herein, we report a three-dimensional (3D) hybrid electrocatalyst that is constructed through in situ anchoring of Co9S8 nanosheets onto the surface of Ni3Se2 nanosheets vertically aligned on an electrochemically exfoliated graphene foil. Benefiting from the synergistic effects between Ni3Se2 and Co9S8, the highly conductive graphene support, and large surface area, the novel 3D hybrid electrode delivers superior electrocatalytic activity toward water reduction in alkaline media, featuring overpotentials of -0.17 and -0.23 V to achieve current densities of 20 and 50 mA cm(-2), respectively, demonstrating an electrocatalytic performance on the top of the Ni3Se2- and Co9S8-based electrocatalysts as reported in literature. Experimental investigations and theoretical calculations confirm that the remarkable activity of the obtained material results from the unique 3D hierarchical architecture and interface reconstruction between Ni3Se2 and Co9S8 through Ni-S bonding, which leads to charge redistribution and thus lowers the energy barrier of hydrogen desorption in the water splitting process. Further integration of the 3D hybrid electrode with a macroporous silicon photocathode enables highly active and sustainable sunlight-driven water splitting in both basic media and real river water. The overall water splitting with 10 mA cm(-2) at a low voltage of 1.62 V is achieved using our hybrid as both anode and cathode catalysts, which surpasses that of the Ir/C-Pt/C couple (1.60 V) for sufficiently high overpotentials.

Citation Y. Hou; M. Qiu; G. Nam; M.Gyu Kim; T. Zhang; K. Liu; X. Zhuang; J. Cho; C. Yuan; X. Feng.Integrated Hierarchical Cobalt Sulfide/Nickel Selenide Hybrid Nanosheets as an Efficient Three-dimensional Electrode for Electrochemical and Photoelectrochemical Water Splitting.. Nano Lett. 2017. doi:10.1021/acs.nanolett.7b01030

Related Elements

Selenium

Selenium Bohr ModelSee more Selenium products. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d10 4s2 4p4. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. Selenium is a non-metal with several allotropes: a black, vitreous form with an irregular crystal structure three red-colored forms with monoclinic crystal structures and a gray form with a hexagonal crystal structure, the most stable and dense form of the element. Elemental SeleniumOne of the most common uses for selenium is in glass production the red tint that it lends to glass neutralizes green or yellow tints from impurities in the glass materials. Selenium was discovered and first isolated by Jöns Jakob Berzelius and Johann Gottlieb Gahn in 1817. The origin of the name Selenium comes from the Greek word "Selênê," meaning moon.

Cobalt

See more Cobalt products. Cobalt (atomic symbol: Co, atomic number: 27) is a Block D, Group 9, Period 4 element with an atomic weight of 58.933195. Cobalt Bohr ModelThe number of electrons in each of cobalt's shells is 2, 8, 15, 2 and its electron configuration is [Ar]3d7 4s2. The cobalt atom has a radius of 125 pm and a Van der Waals radius of 192 pm. Cobalt was first discovered by George Brandt in 1732. In its elemental form, cobalt has a lustrous gray appearance. Cobalt is found in cobaltite, erythrite, glaucodot and skutterudite ores. Elemental CobaltCobalt produces brilliant blue pigments which have been used since ancient times to color paint and glass. Cobalt is a ferromagnetic metal and is used primarily in the production of magnetic and high-strength superalloys. Co-60, a commercially important radioisotope, is useful as a radioactive tracer and gamma ray source. The origin of the word Cobalt comes from the German word "Kobalt" or "Kobold," which translates as "goblin," "elf" or "evil spirit.

Nickel

See more Nickel products. Nickel (atomic symbol: Ni, atomic number: 28) is a Block D, Group 4, Period 4 element with an atomic weight of 58.6934. Nickel Bohr ModelThe number of electrons in each of nickel's shells is [2, 8, 16, 2] and its electron configuration is [Ar]3d8 4s2. Nickel was first discovered by Alex Constedt in 1751. The nickel atom has a radius of 124 pm and a Van der Waals radius of 184 pm. In its elemental form, nickel has a lustrous metallic silver appearance. Nickel is a hard and ductile transition metal that is considered corrosion-resistant because of its slow rate of oxidation. Elemental NickelIt is one of four elements that are ferromagnetic and is used in the production of various type of magnets for commercial use. Nickel is sometimes found free in nature but is more commonly found in ores. The bulk of mined nickel comes from laterite and magmatic sulfide ores. The name originates from the German word kupfernickel, which means "false copper" from the illusory copper color of the ore.

Sulfur

See more Sulfur products. Sulfur (or Sulphur) (atomic symbol: S, atomic number: 16) is a Block P, Group 16, Period 3 element with an atomic radius of 32.066. Sulfur Bohr ModelThe number of electrons in each of Sulfur's shells is 2, 8, 6 and its electron configuration is [Ne] 3s2 3p4. In its elemental form, sulfur has a light yellow appearance. The sulfur atom has a covalent radius of 105 pm and a Van der Waals radius of 180 pm. In nature, sulfur can be found in hot springs, meteorites, volcanoes, and as galena, gypsum, and epsom salts. Sulfur has been known since ancient times but was not accepted as an element until 1777, when Antoine Lavoisier helped to convince the scientific community that it was an element and not a compound.

Related Forms & Applications