Bi vacancy simultaneous manipulation of bulk adsorption and carrier utilization to replenish the mechanism of Cr(VI) photoreduction at universal pH

Adsorption and photocatalytic desorption toward Cr(vi) over defect-induced hierarchically porous UiO-66-(OH)2: a sustainable approach

“…6c), which could be ascribed to the formation of the O–Cr bond. 64,65 Then, the binding energy of Zr–O–Zr shifted from 530.82 eV before adsorption to 530.93 eV after adsorption, indicating that –OH on the Zr–O cluster also provided partial contribution to Cr( vi ) adsorption. Based on the above discussion, there were three Cr( vi ) removal pathways (Fig.…”

Defect Engineering in Bi‐Based Photo/Electrocatalysts for Nitrogen Reduction to Ammonia

“…Cation vacancies (such as Bi vacancies) also play an important role in regulating the electronic structure and surface atomic configuration of semiconductors, which determines the charge separation and transfer process. [63] Cation vacancies can adjust and modify the local coordination environment of the metal center of the electrocatalyst and adjust the electronic structure of nearby atoms. The band gap or intrinsic conductivity can also be adjusted to optimize the adsorption free energy of the electrocatalyst for different intermediates.…”

Synergistic purification of chromium-containing wastewater via adsorption-photocatalysis induced by multiple defect-containing CuS/Cv-CNNs

“…Defects can modulate the surface electronic structure of photocatalysts, 8 whereas the adsorption capacity can be modulated by defects that lower the Gibbs free energy of adsorption, enhance the electrostatic attraction and ion exchange capacity, and so on. [9][10][11] The defect structure of a catalyst can change the structure and local coordination of its surface atoms, exposing and activating them, 12 thus improving its photocatalytic activity by enhanced separation of photogenerated electron-hole (e À -h + ) pairs.…”

“…Of the many types of defect, the introduction of point defects is believed to be effective in improving the adsorption and photocatalytic capabilities of materials. 10,13 Vacancy defects are categorized into three types: anionic vacancy defects, cationic vacancy defects and neutral atomic vacancy defects, all of which have different roles. As electron traps, anionic vacancies can be used to enhance the absorption of visible light and the separation of photogenerated electronhole pairs through the introduction of localized energy levels as well as the provision of more active sites, thus improving the photocatalytic efficiency.…”

“…Li et al synthesized ultrathin Bi 24 O 31 Br 10 nanosheets with Bi vacancies using arginine to achieve ligand-selective stripping of the bismuth atoms. 15 The introduced bismuth vacancies can reduce the Gibbs free energy for adsorption and thus provide new channels for Cr( vi ) adsorption, and can significantly reduce the exciton binding energy and induce the formation of new impurity states, which effectively improve the adsorption and photocatalytic performance of the materials.…”