article · Scientific Reports
A simple hydrothermal method was used to fabricate highly dispersed cobalt-doped zinc sulphide nanostructures on reduced graphene oxide sheets. Structural and optical analyses confirmed that graphite oxide was converted into graphene sheets decorated with crystalline, cuboidal and spheroidal zinc sulphide nanostructures that showed high optical transparency between 180 and 800 nanometres. Computational calculations demonstrated that adding cobalt narrowed the band gap and positioned the conduction bands to facilitate efficient electron transfer to the zinc sulphide. When evaluated in laboratory experiments using water and visible light, the material containing four atomic percent cobalt achieved the highest photocatalytic hydrogen production rate of 7648.9 micromoles per hour. This enhanced performance resulted from a combination of better nanomaterial dispersion, larger surface area, increased optical absorption, and superior transfer of light-generated electrons.
Producing clean hydrogen fuel using sunlight and water offers an attractive pathway to sustainable energy. Developing low-cost, highly active catalysts that work under visible light is a critical challenge in this field. By combining common semiconductor materials with graphene, this research demonstrates a practical design to boost the efficiency of solar-driven hydrogen generation.
This work is relevant to developers of solar hydrogen production systems and clean energy technologies. The catalyst was synthesised via a straightforward hydrothermal method and tested in laboratory-scale experiments using water and visible light. Because the findings are confined to bench-scale testing, the technology is at an early experimental stage and requires substantial scale-up, durability testing, and photoreactor integration before commercial use can be considered.
AI-generated from the published abstract. Always read the original work before citing.
Highly dispersed Cobalt doped ZnS nanostructures were successfully fabricated on the surfaces of graphene sheets via a simple hydrothermal method. X-ray diffraction (XRD), X-ray photocurrent spectroscopy (XPS), Raman spectroscopy (RS), Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) were utilized to analyze the structural characteristics of the cobalt doped ZnS decorated with graphene <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>Co</mml:mi> <mml:mi>x</mml:mi></mml:msub> <mml:msub><mml:mi>Zn</mml:mi> <mml:mrow><mml:mn>1</mml:mn> <mml:mo>-</mml:mo> <mml:mi>x</mml:mi></mml:mrow> </mml:msub> <mml:mi>S</mml:mi></mml:mrow> </mml:math> rGO nanostructures (NSs). UV-visible optical absorption (UV-vis) studies were conducted to investigate their optical properties. In laboratory studies utilizing water and visible light, the photocatalytic activity of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>Co</mml:mi> <mml:mi>x</mml:mi></mml:msub> <mml:msub><mml:mi>Zn</mml:mi> <mml:mrow><mml:mn>1</mml:mn> <mml:mo>-</mml:mo> <mml:mi>x</mml:mi></mml:mrow> </mml:msub> <mml:mi>S</mml:mi></mml:mrow> </mml:math> rGO NSs at (x = 0, 1, 2, 4 and 6 atm.%) were evaluated. Graphite Oxide (GO) was successfully transformed into sheets of graphene and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>Co</mml:mi> <mml:mi>x</mml:mi></mml:msub> <mml:msub><mml:mi>Zn</mml:mi> <mml:mrow><mml:mn>1</mml:mn> <mml:mo>-</mml:mo> <mml:mi>x</mml:mi></mml:mrow> </mml:msub> <mml:mrow><mml:mi>S</mml:mi> <mml:mspace></mml:mspace> <mml:mi>rGO</mml:mi></mml:mrow> </mml:mrow> </mml:math> NSs possessed a crystalline structure according to the findings of XRD, RS and FTIR analysis. SEM investigation showed graphene sheets enhanced with ZnS NSs possessed cuboidal, spheroidal form of structure and displayed a paper like appearance. UV-vis confirmed a noticeable rapid increase in transmittance along the UV wavelength area and confirmed a highly transparent NSs in the wavelength range of (180-800 nm). Calculations using density functional theory (DFT) revealed that the Co NSs have more negative conduction bands than ZnS, allowing for effective electron transfer from cobalt to ZnS and exhibiting a band gap decrease as Co content increased. The <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>Co</mml:mi> <mml:mrow><mml:mn>0.04</mml:mn></mml:mrow> </mml:msub> <mml:msub><mml:mi>Zn</mml:mi> <mml:mrow><mml:mn>0.96</mml:mn></mml:mrow> </mml:msub> <mml:mi>S</mml:mi></mml:mrow> </mml:math> rGO NSs sample had the highest photocatalytic activity, measured at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>7648.9</mml:mn> <mml:mspace></mml:mspace> <mml:mi>μ</mml:mi> <mml:mi>mol</mml:mi> <mml:mspace></mml:mspace> <mml:msup><mml:mrow><mml:mi>h</mml:mi></mml:mrow> <mml:mrow><mml:mo>-</mml:mo> <mml:mn>1</mml:mn></mml:mrow> </mml:msup> </mml:mrow> </mml:math> . A combination of improved dispersion properties, greater surface area, increased absorption and enhanced transfer of photogenerated electrons, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>Co</mml:mi> <mml:mi>x</mml:mi></mml:msub> <mml:msub><mml:mi>Zn</mml:mi> <mml:mrow><mml:mn>1</mml:mn> <mml:mo>-</mml:mo> <mml:mi>x</mml:mi></mml:mrow> </mml:msub> <mml:mi>S</mml:mi></mml:mrow> </mml:math> rGO NSs increased the photocatalytic hydrogen generation activity.
This page summarises published work. The authoritative version sits with the publisher.
DOI: 10.1038/s41598-024-72645-z
Is something wrong with this record? Report it or request removal.
Discussion
Have you built on this work, tried to replicate it, or seen it applied in practice? Share what you know. Verified researchers and MARATTO™ domain experts can open a discussion, and any member can reply. Contributions are reviewed before they appear.
No discussion yet. Open the first thread.
New to MARATTO™? Create a free account.
