TY - JOUR
T1 - Water/oil nanoemulsion-based synthesis of BixSn6-2xSy (0.33 ≤ × ≤ 2.95) semiconductor QDs for efficient photocatalytic degradation of MB dye
AU - Negem, Mosaad
AU - Miller, David
AU - Irvine, John
AU - Heakal, Fakiha El-Taib
N1 - Funding: Open-access funding is provided by the Science, Technology & Innovation Funding Authority (STDF) in cooperation with the Egyptian Knowledge Bank (EKB). The authors would like to thank the University of St Andrews and the Egyptian Government for funding this work.
PY - 2023/4/1
Y1 - 2023/4/1
N2 - The development of efficient photocatalysts for the photodegradation of organic dyes in wastewater is highly worthwhile. Herein, the nanoemulsion tactic was utilized to synthesize BixSn6-2xSy (0.33 ≤ x ≤ 2.95) photocatalysts with morphological structures that changed from nanowhiskers to quantum dots (QDs). The optical properties of these materials were examined by UV-visible absorbance spectroscopy and photoluminescence, while Mott-Schottky analysis was utilized to study their electronic properties. BixSn6-2xSy materials exhibit appreciable absorption in the UV-visible light range with a direct band gap that increases from 1.23 to 1.46 eV. Both crystal structure and composition greatly affect the photocatalytic activity of BixSn6-2xSy semiconductors. Among the various synthesized photocatalysts, BiSn4S4.5 can efficiently photodegrade methylene blue dye (MB) in the shortest time under UV-visible light. The photocatalytic activity is positively affected by the change of crystal structure from orthorhombic to cubic symmetry. Based on the Mott-Schottky plots, the flat band potential (Efb) and the semiconductor behavior of the fabricated BixSn6-2xSy nanomaterials were determined. The obtained Efb values for SnS, Bi0.33Sn5.34S5.8, BiSn4S5.5, and Bi2.14Sn1.71S4.7 are -0.18 V, -0.42 V, -0.53 V, and -0.51 V (vs. Ag/AgCl), respectively. The Efb value is clearly shifted towards more negative potential values with increasing the Bi molar ratio (x). However, Bi2.95Sn0.1S4.5 semiconductor was found to be of n-type character, having a positive Efb value of +0.66 V (vs. Ag/AgCl). Photocurrent and EIS responses confirm the high stability and photocatalytic activity of BiSn4S5.5, which also achieves the lowest charge transfer resistance. The modified electronic properties of the BixSn6-2xSy semiconductors significantly improve their photocatalytic activity, rendering them to be promising absorbers for sunlight harvesting applications.
AB - The development of efficient photocatalysts for the photodegradation of organic dyes in wastewater is highly worthwhile. Herein, the nanoemulsion tactic was utilized to synthesize BixSn6-2xSy (0.33 ≤ x ≤ 2.95) photocatalysts with morphological structures that changed from nanowhiskers to quantum dots (QDs). The optical properties of these materials were examined by UV-visible absorbance spectroscopy and photoluminescence, while Mott-Schottky analysis was utilized to study their electronic properties. BixSn6-2xSy materials exhibit appreciable absorption in the UV-visible light range with a direct band gap that increases from 1.23 to 1.46 eV. Both crystal structure and composition greatly affect the photocatalytic activity of BixSn6-2xSy semiconductors. Among the various synthesized photocatalysts, BiSn4S4.5 can efficiently photodegrade methylene blue dye (MB) in the shortest time under UV-visible light. The photocatalytic activity is positively affected by the change of crystal structure from orthorhombic to cubic symmetry. Based on the Mott-Schottky plots, the flat band potential (Efb) and the semiconductor behavior of the fabricated BixSn6-2xSy nanomaterials were determined. The obtained Efb values for SnS, Bi0.33Sn5.34S5.8, BiSn4S5.5, and Bi2.14Sn1.71S4.7 are -0.18 V, -0.42 V, -0.53 V, and -0.51 V (vs. Ag/AgCl), respectively. The Efb value is clearly shifted towards more negative potential values with increasing the Bi molar ratio (x). However, Bi2.95Sn0.1S4.5 semiconductor was found to be of n-type character, having a positive Efb value of +0.66 V (vs. Ag/AgCl). Photocurrent and EIS responses confirm the high stability and photocatalytic activity of BiSn4S5.5, which also achieves the lowest charge transfer resistance. The modified electronic properties of the BixSn6-2xSy semiconductors significantly improve their photocatalytic activity, rendering them to be promising absorbers for sunlight harvesting applications.
KW - Semiconductor quantum dots
KW - Mott-Schottky plots
KW - Metal chalcogenides
KW - Nanoemulsion tactic
KW - MB photodegradation
KW - Direct band gap
U2 - 10.1007/s11356-023-26596-z
DO - 10.1007/s11356-023-26596-z
M3 - Article
C2 - 37000392
SN - 0944-1344
VL - 30
SP - 58998
EP - 59012
JO - Environmental Science and Pollution Research
JF - Environmental Science and Pollution Research
ER -