Application of a Functionalized K₁₋ₓNiₓNbO₃ Structure: Enhancing the Photocatalytic Activity of a CdS/K₁₋ₓNiₓNbO₃ Composite
Abstract
Herein we report a K₁₋ₓNiₓNbO₃ composite undergoing a phase transition from orthorhombic to rhombohedral, resulting in a Ni particle and a short Nb–O^(δ-) on the surface caused by a structural distortion. The Ni particles are dispersed on the overall surface of the structure, and the short bonded Nb–O^(δ-) sticks out to the structure interstices on the surface. The properties of the structure and surface of K₁₋ₓNiₓNbO₃ are defined by spectroscopic analysis of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Raman, nuclear magnetic resonance (¹H NMR), and X-ray photoelectron spectroscopy (XPS). This unique surface property enables the formation of two hybrid composites that deposit CdS on either site of the Ni/Ni–H particle or short Nb–O^(δ-), resulting in a different interface between CdS and K₁₋ₓNiₓNbO₃. The one that deposits CdS on the Ni/Ni–H particles is denoted as SCdS/K₁₋ₓNiₓNbO₃, and the other that deposits CdS on the short Nb–O^(δ-) is denoted as CdS/K_(0.9)Ni_(0.1)NbO₃. SCdS/K₁₋ₓNiₓNbO₃ exhibits a delayed kinetics for CdS photoinduced electrons compared to that of CdS/K₁₋ₓNiₓNbO₃ as decayed fluorescence at ca. 311 ps, while indicating ca. 238 ps for CdS/K₁₋ₓNiₓNbO₃. As a result, SCdS/K₁₋ₓNiₓNbO₃ exhibits a superior photocatalytic activity for H₂ production of ca. 3.1 mmol g⁻¹ h⁻¹ compared to CdS/K₁₋ₓNiₓNbO₃ with ca. 2.7 mmol g⁻¹ h⁻¹.
Additional Information
© 2023 American Chemical Society. The authors gratefully acknowledge the support of the Hydrogen Energy R&D Center of 21st Century Frontier Research and Development Program of the Ministry of Science and Technology of Korea for financial support. We are especially grateful to Dr. Oh-Hoon Kwon for allowing us to use the facility of TCSPC and to Dr. Sonjong Hwang, who helped us for NMR data analysis as a director of the solid NMR facility. Support from Hydrogen Energy R&D Center of the 21st Century Frontier Research and Development Program of the Ministry of Science and Technology of Korea. Author Contributions: S.Y.R. performed the research, data analysis, and wrote a draft of the manuscript. M.R.H., the lab director and supervising professor, reviewed the manuscript. The authors declare no competing financial interest.Additional details
- Alternative title
- Application of a Functionalized K1–xNixNbO3 Structure: Enhancing the Photocatalytic Activity of a CdS/K1–xNixNbO3 Composite
- Eprint ID
- 122277
- Resolver ID
- CaltechAUTHORS:20230714-170229200.3
- Ministry of Science and Technology (Korea)
- Created
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2023-07-14Created from EPrint's datestamp field
- Updated
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2023-07-14Created from EPrint's last_modified field