Hollow Sr/Rh-codoped TiO₂ photocatalyst for efficient sunlight-driven organic compound degradation

Abstract

Sunlight-driven photocatalysis has emerged as a potential technology to address organic pollutant issues.

Complex ZnO-TiO2 Core–Shell Flower-Like Architectures with Enhanced Photocatalytic Performance and Superhydrophilicity without UV Irradiation

“…In addition, the hollow TiO 2 flowers were more photoactive compared with the TiO 2 particles ( k = 0.020 min –1 ) because of their unique architecture and morphology. More specifically, it is well established in the literature that photocatalysis is a morphology-dependent process, , and hollow TiO 2 structures, such as the ones presented in this work, are expected to exhibit an enhanced photocatalytic performance compared to the respective bulk spherical particles. − This superior behavior can be attributed to the higher accessibility of the dye molecules to the photocatalyst’s surface and more active reaction sites for the redox reactions to proceed, as well as the reduced diffusion distance of the photogenerated charge carriers and the superior light harvesting ability of the photocatalyst. − …”

Insights into the TiO2-Based Photocatalytic Systems and Their Mechanisms

“…The mechanism of cation doping is essentially to tune the Fermi level and electronic structure of d-electron configuration in TiO 2 , thereby to tune the energy levels to absorb the visible light energy and to enhance the overall photocatalytic efficiency of the system as shown in Figure 4a Consequently, there have been many cations doped in TiO2 towards enhancing its PC activities. In such cation doping, TiO2 has been doped with the (i) transition metals such as Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Cd, and W [73][74][75][76][77][78][79][80][81][82][83][84]; (ii) rare-earth metals such as Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Yb, and La [85][86][87][88][89]; and (iii) other metals such as Li, Mg, Ca, Se, Sr, Al, Sn, and Bi [90][91][92][93][94][95][96][97]. In the case of rare earth elements doping, the electronic configurations such as 4f, 5d, and 6s are found to be favorable to tune the band edge positions, density of states, and width of VB and CB via altering the crystal, electronic, and optical structures in TiO2 [98][99][100].…”

Theoretical study on cation codoped SrTiO3 photocatalysts for water splitting

“…Since most of the metal-oxide photocatalysts, including perovskites, have too large optical band gaps for visible light, many efforts have been directed to a reduction by chemical doping. For example, cation-cation codoping of TiO 2 has been investigated experimentally for (Ni/Zn/Mo, Fe) [1][2][3][4], (Co/Nb/Ta, Ni) [5][6][7], (Y, V) [8], (Sb, Cr) [9], (Rh, Sr) [10] and theoretically for (Ni, Fe) [11], (Rh, Nb) [12], (Mo/W, Mg/Ca) [13], (La, Mn) [14]. Other studies have addressed (La, Ag) codoping of CaTiO 3 [15], (Sn, Ga) codoping of BiFeO 3 [16], and (W, Fe/Mo) codoping of BiVO 4 [17,18].…”