Oxygen-Induced Bi⁵⁺-Self-Doped Bi₄V₂O₁₁ with a p–n Homojunction Toward Promoting the Photocatalytic Performance

Abstract

Bi-self-doped BiVO (Bi-BVO) nanotubes with p-n homojunctions are fabricated via an oxygen-induced strategy. Calcinating the as-spun fibers with abundant oxygen plays a pivotal role in achieving Bi self-doping. Density functional theory calculations and experimental results indicate that Bi self-doping can narrow the band gap of BiVO, which contributes to enhancing light harvesting. Moreover, Bi self-doping endows BiVO with n- and p-type semiconductor characteristics simultaneously, resulting in the construction of p-n homojunctions for retarding rapid electron-hole recombination. Benefiting from these favorable properties, Bi-BVO exhibits a superior photocatalytic performance in contrast to that of pristine BiVO. Furthermore, this is the first report describing the achievement of p-n homojunctions through self-doping, which gives full play to the advantages of self-doping.

Facile synthesis of a ZnO–BiOI p–n nano-heterojunction with excellent visible-light photocatalytic activity

“…Both pure BiOI and the nanocomposite sample consist of a doublet which can be well-assigned to Bi 4f 5/2 at 164.5 eV and Bi 4f 3/2 at 159.2 eV with an energy difference of 5.3 eV [39,46], revealing that +3 is the main valence state of the Bi element in B-1 and the nanocomposite sample [17]. A pair of satellite peaks centered at about 1.8 eV higher than the main peaks can be identified as Bi 5+ defects and agreed well with the reported values [30,32]. As shown in Fig.…”

“…Furthermore, coupling n-type semiconductor photocatalysts to p-type to form p–n heterojunctions could promote increased photocatalytic activity efficiency. Once the p–n junction has been formed, the inner electric field between the inner surface of two semiconductors will promote the separation efficiency of photoinduced electron–hole pairs [30–31]. …”

Accurate Control of VS2 Nanosheets for Coexisting High Photoluminescence and Photothermal Conversion Efficiency

“…The characteristic peaks of V−OH and chemisorbed water can be detected at 531.30 and 532.90 eV in the three samples. An extra peak at 530.50 eV ascribed to substoichiometric VO 2− x only can be perceived in VO 2 (D), supporting by its V 2p spectra …”

Bi5+, Bi(3−x)+, and Oxygen Vacancy Induced BiOClxI1−x Solid Solution toward Promoting Visible‐Light Driven Photocatalytic Activity

“…It demonstrates that the defective oxygen vacancy achieves the conversion of CO 2 to CH 4 and the conversion of N 2 to NH 4 . The recent introduction of Bi 5+ ion defects has resulted in an n‐p type transformation in semiconductors, which greatly improves the photocatalytic activity . However, most of the current research is aimed at single defects, such as oxygen vacancy or ion doping; understanding the mechanism of multiple defects on solar‐driven photocatalytic performance remains elusive.…”