TY - JOUR
T1 - Rare earth metal doped molybdenum sulfide microflowers reinforced with graphene for the photocatalytic annihilation of ciprofloxacin drug
AU - Aldrdery, Moutaz
AU - Aadil, Muhammad
AU - El Jery, Atef
AU - Khalid, Awais
AU - El-Aassar, Mohamed R.
AU - Alomayri, Thamer
AU - Rafea, Mohamed Abdel
AU - Altayar, Abdullah Riyad
AU - Alrahili, Mazen R.
N1 - Publisher Copyright:
© 2025 Elsevier B.V.
PY - 2025/3
Y1 - 2025/3
N2 - The photocatalytic activity of molybdenum disulfide (MoS2) is often hindered by its limited visible light absorption and substantial charge carrier recombination. In this study, holmium (Ho3+)-doped MoS₂ (Ho@MoS2) has been developed through a facile hydrothermal method. The Ho@MoS2 was then incorporated into graphene derivatives, i.e., reduced graphene oxide (rGO), via ultrasonication. The physicochemical properties of the synthesized materials were characterized using X-rays diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermal gravimetric analysis, electrochemical impedance analysis, ultraviolet-visible spectroscopy, current-voltage, and Mott-Schottky measurements. X-rays diffraction analysis confirmed the formation of the hexagonal phase for both MoS2 and Ho@MoS2, while SEM images revealed micro-flower structures encased within graphene sheets. Ultraviolet-visible spectroscopy showed enhanced light absorption and a reduced band gap for Ho@MoS2 (1.86 eV) compared to pure MoS₂ (1.99 eV). Mott-Schottky and electrochemical impedance analyses indicated improved charge carrier generation and lower internal resistance following Ho3+ doping and graphene integration. When applied for the photocatalytic treatment of a representative pharmaceutical drug, Ciprofloxacin (CIP), Ho@MoS2-rGO demonstrated a significantly enhanced degradation efficiency with 96.1 % CIP removal within 105 min, which is approximately 2.4 and 1.5 times higher than that of Ho@MoS2 (63.2 %) and MoS2 (39.8 %), respectively. This enhanced photocatalytic activity is attributed to the electron-capturing ability of Ho3+ ions, the high conductivity of Ho@MoS2-rGO, favorable band potential (−1.58 V), and reduced series resistance (177 Ω). Additionally, the semiconductor‑carbon (S[sbnd]C) heterojunction within Ho@MoS₂-rGO further promotes efficient charge separation and mobility of reactive oxygen species (ROS). The obtained outstanding photocatalytic performance of Ho@MoS2-rGO offers its potential use for wastewater treatment.
AB - The photocatalytic activity of molybdenum disulfide (MoS2) is often hindered by its limited visible light absorption and substantial charge carrier recombination. In this study, holmium (Ho3+)-doped MoS₂ (Ho@MoS2) has been developed through a facile hydrothermal method. The Ho@MoS2 was then incorporated into graphene derivatives, i.e., reduced graphene oxide (rGO), via ultrasonication. The physicochemical properties of the synthesized materials were characterized using X-rays diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermal gravimetric analysis, electrochemical impedance analysis, ultraviolet-visible spectroscopy, current-voltage, and Mott-Schottky measurements. X-rays diffraction analysis confirmed the formation of the hexagonal phase for both MoS2 and Ho@MoS2, while SEM images revealed micro-flower structures encased within graphene sheets. Ultraviolet-visible spectroscopy showed enhanced light absorption and a reduced band gap for Ho@MoS2 (1.86 eV) compared to pure MoS₂ (1.99 eV). Mott-Schottky and electrochemical impedance analyses indicated improved charge carrier generation and lower internal resistance following Ho3+ doping and graphene integration. When applied for the photocatalytic treatment of a representative pharmaceutical drug, Ciprofloxacin (CIP), Ho@MoS2-rGO demonstrated a significantly enhanced degradation efficiency with 96.1 % CIP removal within 105 min, which is approximately 2.4 and 1.5 times higher than that of Ho@MoS2 (63.2 %) and MoS2 (39.8 %), respectively. This enhanced photocatalytic activity is attributed to the electron-capturing ability of Ho3+ ions, the high conductivity of Ho@MoS2-rGO, favorable band potential (−1.58 V), and reduced series resistance (177 Ω). Additionally, the semiconductor‑carbon (S[sbnd]C) heterojunction within Ho@MoS₂-rGO further promotes efficient charge separation and mobility of reactive oxygen species (ROS). The obtained outstanding photocatalytic performance of Ho@MoS2-rGO offers its potential use for wastewater treatment.
KW - Ceramic
KW - Hydrothermal
KW - Nanocomposite
KW - Photocatalysis
KW - Ultrasonication
UR - http://www.scopus.com/inward/record.url?scp=85216853533&partnerID=8YFLogxK
U2 - 10.1016/j.diamond.2025.112072
DO - 10.1016/j.diamond.2025.112072
M3 - Article
AN - SCOPUS:85216853533
SN - 0925-9635
VL - 153
JO - Diamond and Related Materials
JF - Diamond and Related Materials
M1 - 112072
ER -
