Facile synthesis of 2D/0D Bi2O3/MnO2 Z-scheme heterojunction for enhanced visible light-assisted photocatalytic degradation of acetaminophen

Visible Light-Assisted Degradation of Sulfamethoxazole on 2D/0D Sulfur-Doped Bi2O3/MnO2 Z-Scheme Heterojunction Immobilized Photocatalysts

“…Further, no characteristic peaks attributed to the S element were found in the 2S–Bi 2 O 3 FTIR spectrum, which could be due to the overlap of these peaks or the low content of S in Bi 2 O 3 . Meanwhile, the FTIR spectra of the 2S-BOMO nanocomposite indicated the presence of all of the distinctive vibrational peaks of 2S–Bi 2 O 3 and MnO 2 (reported in our previous study). The presence of distinct peaks of 2S-BOMO in the immobilized 2S-BOMO indicated its successful deposition on the surface of the clay beads.…”

“…Additionally, the HRTEM image (Figure j) and the associated SAED patterns (Figure k) show the crystalline nature of 2S-BOMO CCB. The interplanar spacing of 0.321 and 0.242 nm of the distinct lattice fringes comply with the {2 0 1} and {−1 1 1} crystal planes of 2S–Bi 2 O 3 and MnO 2 , respectively (Figure j). , The SAED pattern corresponding to the {−1 1 1} and {2 0 1} facet at ∼28 and ∼37° in the XRD patterns contributes to the anticipated 2S-BOMO heterojunction formation …”

“…The distinct strong peaks located at BEs of 158.3 and 163.6 eV are ascribed to Bi 4f 7/2 and Bi 4f 5/2 of the Bi 3+ state of 2S–Bi 2 O 3 , respectively, whereas the small peak at 159.3 eV due to S 2 p 3/2 suggests the presence of S 2– species in the composites. It is also noted that the inclusion of S in the Bi 2 O 3 lattice has resulted in about a negative shift of the Bi 4f 7/2 peak by ∼0.1 eV . Further, the lower electronegativity of S compared to O could lead to the occupancy of the S in the O sites of the Bi 2 O 3 crystals. , Meanwhile, the O 1s core level spectrum displayed in Figure d fitted into three peaks positioned at 529.3, 529.7, and 531.5 eV corresponding to the lattice oxygen (O L ) of 2S-BOMO, hydroxyl groups (O H ), and oxygen vacancies (O V ), respectively. , In addition, a higher peak area of S compared to the oxygen vacancies could also account for the doping of S atoms in the interstitial lattice positions. , Further, the S 2p spectrum in Figure e displayed the appearance of two distinct peaks at 158.4 and 163.7 eV (S 2– species) in the 2S-BOMO nanocomposite .…”

“…XRD diffractograms of as-prepared 2S–Bi 2 O 3 , 2S-BOMO, uncoated clay beads, and 2S-BOMO CCB are displayed in Figure c. It is noted that the findings on principal diffraction peaks of pure 2S–Bi 2 O 3 appeared at 2θ of 27.6, 31.1, 32.9, 45.7, 53.8, and 55.6° corresponding to the {2 0 1}, {0 0 2}, {2 2 0}, {2 2 2}, {2 0 3}, and {2 1 3} crystal planes, respectively, and agreed well with the tetragonal phase β-Bi 2 O 3 (JCPDS: 027-0050). , Moreover, no additional peak(s) of sulfide or sulfoxide were detected in the XRD patterns of 2S–Bi 2 O 3 (Figure c). Therefore, it is anticipated that doping of S occurred only most likely during the calcination stage .…”

“…The surface groups of 2S–Bi 2 O 3 , 2S-BOMO, uncoated clay beads, and 2S-BOMO CCB were investigated by FTIR, as represented in Figure f. The bare 2S–Bi 2 O 3 showed the presence of peaks in the range of 500–700 and 829 cm –1 attributed to the Bi–O bond stretching vibrations and Bi–O–Bi bond vibrations, respectively. , In addition, the presence of the characteristic C–H (623 cm –1 ) and C–OH (1071 cm –1 ) bands could be ascribed to the chemisorption of moisture . Further, no characteristic peaks attributed to the S element were found in the 2S–Bi 2 O 3 FTIR spectrum, which could be due to the overlap of these peaks or the low content of S in Bi 2 O 3 .…”