AgIn_xGa_1−xS₂solid solution nanocrystals: synthesis, band gap tuning and photocatalytic activity

Controllable Synthesis of Bandgap‐Tunable CuSxSe1−x Nanoplate Alloys

“…This result is in good agreement with Vegards Law that the bandgap of an alloy typically varies non‐linearly whereas the lattice constant varies linearly with its composition . The tunable bandgap might make the alloyed CuS x Se 1− x nanoplates suitable for promising applications in photocatalysis and optoelectronic devices . As in the cases of binary copper sulfides and selenides, a wide and strong NIR absorption of the CuS x Se 1− x nanoplates owing to localized surface plasmonic resonance of free holes in the valence band was revealed (Figure a).…”

AgInS2-Coated Upconversion Nanoparticle as a Photocatalyst for Near-Infrared Light-Activated Photodynamic Therapy of Cancer Cells

“…The generated O 2 –• was further reacted with photogenerated holes to produce H 2 O 2 and eventually • OH by further steps . However, in this case, the holes were not responsible for the direct formation of • OH from H 2 O, since the VB potential ( E VB ) of AIS (1.36 eV) is more negative than E 0 of • OH/OH – (2.38 eV vs NHE). , Therefore, these holes could also be available for the direct oxidation of MB, since the E VB is more positive than E 0 of MB •+ /MB (1.08 V vs NHE). , Again, in our spectroscopic studies, we observed the significant generation of 1 O 2 during the photocatalysis process, which can be attributed to the conversion of dissolved O 2 to 1 O 2 in the presence of holes, since the reduction potential of 1 O 2 /O 2 –• (0.95 eV) is less positive than E VB of AIS. , Therefore, it was observed that these photogenerated O 2 –• , • OH, 1 O 2 , and h + generated in the system are the active species for MB degradation under 980 nm NIR light illumination.…”

“…First, upon illuminating the UCN@AIS NPs by a 980 nm laser, the lower energy NIR energy was converted to a higher visible light energy by an upconversion procedure. − Due to the occurrence of AIS in a close proximity toward the UCN, the visible light was then transferred by the LRET mechanism, as described above, and the AIS NPs were excited, leading to the formation of electron–hole pairs . The edge potentials of valence band (VB) and conduction band (CB) of AIS were calculated by the following equations: E VB = X – E e + 0.5 E g and E CB = E VB – E g , where E g is the band gap energy of AIS ( E g = 2.12 eV, obtained from UV–vis absorbance), E VB is the VB edge potential, E CB is the CB edge potential, X is the electronegativity of AIS (4.8 eV), and E e is the energy for free electrons on a hydrogen scale (4.5 eV) . From the above-mentioned equations, E VB and E CB were measured to be 1.36 and −0.76 eV, respectively.…”

“…16 The edge potentials of valence band (VB) and conduction band (CB) of AIS were calculated by the following equations: E VB = X − E e + 0.5E g and E CB = E VB − E g , where E g is the band gap energy of AIS (E g = 2.12 eV, obtained from UV−vis absorbance), E VB is the VB edge potential, E CB is the CB edge potential, X is the electronegativity of AIS (4.8 eV), and E e is the energy for free electrons on a hydrogen scale (4.5 eV). 52 From the above-mentioned equations, E VB and E CB were measured to be 1.36 and −0.76 eV, respectively. The generated electrons and holes were then transferred to the interface of nanocrystals and water solution for further redox reaction to generate ROS.…”

“…16,39 Again, in our spectroscopic studies, we observed the significant generation of 1 O 2 during the photocatalysis process, which can be attributed to the conversion of dissolved O 2 to 1 O 2 in the presence of holes, since the reduction potential of 1 O 2 /O 2 −• (0.95 eV) is less positive than E VB of AIS. 52,55 Therefore, it was observed that these photogenerated O 2 −• , • OH, 1 O 2 , and h + generated in the system are the active species for MB degradation under 980 nm NIR light illumination.…”