Efficient photodechlorination of chlorophenols on polarized MZnB5O10 (M = Na and K) nonlinear optical materials

Exploring the Origin of High Dechlorination Activity in Polar Materials M2B5O9Cl (M = Ca, Sr, Ba, Pb) with Built-In Electric Field

“…One can observe in Figure 2b that no chloride ion is produced as in the absence of a catalyst or 2,4-DCP under UV light irradiation. The dechlorination of 2,4-DCP by UV light in the presence of M 2 B 5 O 9 Cl follows a pseudo-first-order process: the rate constant (k) for photodechlorination at BBC, SBC, CBC, and PBC was 0.27, 0.21, 0.096, and 0.062 min −1 , respectively, far higher than that of the commercial P25 TiO 2 catalyst (0.018 min −1 ), 7 clearly exhibiting the outstanding photocatalytic activity of M 2 B 5 O 9 Cl toward 2,4-DCP dechlorination. The relative photocatalytic activities of the catalysts for chlorophenols degradation are in the following order: BBC > SBC > CBC > PBC.…”

“…Recently, series of NCS nonlinear optical materials, K 3 B 6 O 10 Br, Na 3 VO 2 B 6 O 11 , and MZnB 5 O 10 (M = Na and K), have been proven to perform with a higher photocatalytic activity than that of commercial P25 TiO 2 in dechlorination of chlorophenols under UV or UV–vis light irradiation. These results illustrate that the materials with built-in electric fields can generate spontaneous polarization that works as a driving force to direct the separation of photogenerated electrons and holes and highly reduces the charge recombination.…”

“…By combination with atomic force microscopy (AFM), Kelvin probe force microscopy (KPFM) can enable nanometer-scale imaging of the surface potential on a wide range of polar structured materials . Due to the influence of the polar structure, the separation of charge carriers can help to reduce the recombination of e–h pairs. , With all of this in mind, the noncentrosymmetric pentaborate halides, M 2 B 5 O 9 Cl (M = Ca, Sr, Ba, Pb, M 2 B 5 O 9 Cl), have been of great interest for potential applications of their luminescence and nonlinear optical properties. , On the basis of our previous work, − herein, for the first time, we report their new photocatalytic properties as efficient photodegradation materials. The M 2 B 5 O 9 Cl samples were prepared by impregnation of the alkaline earth metal ions on chloro-borates.…”

“…2,3 Noncentrosymmetric (NCS) crystal structures with internal-built electric field have been drawing massive attention owing to their wide range of potential applications to the field of optical communications, sensors, energy harvest, detectors, memories, and so forth. 4 Recently, series of NCS nonlinear optical materials, K 3 B 6 O 10 Br, 5 Na 3 VO 2 B 6 O 11 , 6 and MZnB 5 O 10 (M = Na and K), 7 have been proven to perform with a higher photocatalytic activity than that of commercial P25 TiO 2 in dechlorination of chlorophenols under UV or UV−vis light irradiation. These results illustrate that the materials with built-in electric fields can generate spontaneous polarization that works as a driving force to direct the separation of photogenerated electrons and holes and highly reduces the charge recombination.…”

High-Efficiency Visible Light Responsive Sulfide KSb5S8 Photocatalyst with a Layered Crystal Structure

“…(Figure 5b). To quantitatively study the reaction kinetics, the photocatalytic processes can be understood by the Langmuir-Hinshelwood kinetics model, assuming that the reaction conformed to a pseudo first order model [24].…”