Enhanced photoactivity of antimony phosphates by substitution of H+, Cu2+ and N3− in the K3Sb3P2O14·xH2O crystal lattice

Enhancement of Photocatalytic Activity of Sodium Bismuth Titanate by Doping with Copper, Silver, and Tin Ions

“…The ionic radius of Ag + (1.28 Å) is higher than the ionic radius of Na + (1.18 Å) and replacement of Na + by Ag + leads to an increase in the unit cell parameter and hence the d ‐lines should shift towards lower 2 θ values. Similarly, the ionic radius of Cu 2+ (0.73 Å) [or Sn 2+ (0.93 Å)] is lower than Na + and incorporation of Cu 2+ (or Sn 2+ ) into NBT lattice leads to a decrease in unit cell parameter and d ‐lines should shift towards higher 2 θ values , . However, in the present investigation, the d ‐lines of CNBT and SNBT are also shifted towards lower 2 θ values.…”

“…The obtained indirect bandgap energies of NBT, CNBT, SNBT, and ANBT are found to be 3.1, 2.8, 2.4, and 2.1 eV, respectively. However, metal ion doping may cause a redshift of absorption edge, because of intermixing of Cu 3d / Sn 5s / Ag 4d orbitals with O 2p orbital in the valence band leading to lower bandgap energy , . For instance consider the examples of NaSbO 3 and AgSbO 3 , the bandgap energy of NaSbO 3 is 4.9 eV while its silver analogue, AgSbO 3 has 2.6–2.7 eV .…”

“…Further, the presence of Ag nanoparticles on the surface of NBT catalyst is also beneficial for improving the visible‐light absorption and photocatalytic activity (evidence by DRS results) , . In general, the photocatalytic activity depends on the nature of pollutant, surface area, crystallite size, bandgap energy, and electron‐hole recombination rate, etc.…”

Syntheses and Structural Characterization of A3Sb3P2O14⋅3H2O (A=Rb, Cs, Tl and NH4) Phosphates; Facile Aqueous Ion Exchange Reactions of K3Sb3P2O14⋅3H2O

“…K 3 Sb 3 P 2 O 14 ⋅3H 2 O, unlike KSbP 2 O 8 , undergoes ion‐exchange of potassium ions with molten nitrates of other alkali metal ions,,, at high temperatures of ∼400 °C. Their ion‐exchange capabilities at room temperature in aqueous medium are largely unexplored and the ion‐exchange reaction of K 3 Sb 3 P 2 O 14 ⋅3H 2 O with aqueous Cu 2+ ions was the only example reported . The ion‐exchanged products containing alkali metal ions, A 3 Sb 3 P 2 O 14 ⋅3H 2 O ( A =Na, Rb, Cs), were reported,, to be thus obtained at room and high temperatures from H 3 Sb 3 P 2 O 14 ⋅3H 2 O and K 3 Sb 3 P 2 O 14 ⋅3H 2 O respectively.…”

Tailoring the luminescence and photocatalytic activity of KMn4(PO4)3by Anions (N3‐and S2‐) doping

“…However, reports pertaining to catalytic properties of these phosphates are limited. Recently, we have studied cation (or anion) doped phosphate materials such as K 5 Sb 5 P 2 O 20 , Ba 2 TeO(PO 4 ) 2 , KMnP 3 O 9 , KSb 2 PO 8 , K 3 Sb 3 P 2 O 14 xH2O and Na 3 SbO(PO 4 ) 2 . Compared with parent materials, doped samples exhibited better photocatalytic activity towards dye degradation process.…”