One‐pot combustion synthesis and efficient broad spectrum photoactivity of Bi/BiOBr:Yb,Er/C photocatalyst

Abstract

A highly efficient broad spectrum responsive Bi/BiOBr:Yb,Er/C ternary composite was synthesized by a simple one-pot combustion method using nitrates and citric acid as raw materials. Experimental results show that Er 3+ /Yb 3+ were successfully doped into BiOBr lattice, and metallic Bi nanoparticles and carbon species were formed simultaneously. Compared with pure BiOBr and Bi/BiOBr/C, as-synthesized Bi/BiOBr:Yb,Er/C ternary photocatalyst is highly responsive in the UV-visible-NIR range, and possesses the best photodegradation performance for Rhodamine B, phenol, and imidacloprid under visible, NIR, or solar light irradiation, which can be attributed to the synergetic effects of surface plasma resonance of metallic Bi, up-conversion transition of Er 3+ and heterojunctions (Bi/BiOBr, Bi/C, and BiOBr/C). Moreover, a plausible mechanism was given, the main active species, and photostability of samples were studied. The solar light photoactivity and influences of pH value and anions (Cl À , SO 4 2À , CO 3 2À , HCO 3 À , and NO 3 À )were also investigated. This study highlights the advantages of synergetic effects of SPR, up-conversion and heterojunctions, which provides a useful guide toward the rational design of broad spectrum (UV-visible-near infrared) photocatalysts.

Synthesis and photocatalytic properties of sunlight‐responsive BiOBr–CoWO4 heterostructured nanocomposites

“…Since the introduction of TiO 2 as a photocatalyst, the search for new heterogeneous photocatalysts with suitable bandgaps has begun to produce the required efficiency for practical applications. From the viewpoint of enhancing separation efficiency of photogenerated charge carriers, various photocatalysts such as Cu 2 S/Zn 0.5 Cd 0.5 S, BiOBr:Yb 3+ ,Er 3+ /g‐C 3 N 4 , CoFe 2 O 4 /Cd 0.9 Zn 0.1 S, Bi/BiOBr:Yb,Er/C, Cu 2 S/Zn 0.5 Cd 0.5 S, BiOBr–Ag 8 SnS 6 , etc., have been explored for harvesting visible light for H 2 production and elimination of organic contaminants from wastewater.…”

0D CoP cocatalyst/ 2D g‐C3N4 nanosheets: An efficient photocatalyst for promoting photocatalytic hydrogen evolution

“…Its effectivity promotes the separation and transmission of photogenerated charges, reduces the recombination rate of photogenerated carriers in semiconductors, and enhances photocatalytic efficiency. These heterogeneous such as precious metal precipitation (Au, Pt, Pd, Ag), nonmental deposition (S, Br, B), semiconductor heterojunction modification (such as: TiO 2 , WO 3 , BiOBr, CdS), which can greatly widen the application of the g‐C 3 N 4 ‐based nanomaterials. Although several cocatalysts have been introduced into the photocatalytic system, the efficiency of photocatalytic hydrogen production needs to be further improved.…”

Synthesis and up‐conversion of Er3+ and Yb3+ Co‐doped LiY(MoO4)2@SiO2 for optical thermometry applications

“…Therefore, it is urgent to seek materials with much higher fluorescence efficiency. Er 3+ ‐Yb 3+ co‐doped UC materials have been considered as promising candidates for such a demand . As a sensitizer, Yb 3+ has a large absorption cross section in the near infrared region (around 980 nm) with a bigger penetration depth, which can significantly enhance the UC emission of Er 3+ by absorbing infrared pumping light.…”

“…Therefore, the Er 3+ –Yb 3+ co‐doped materials promise high conversion efficiency without strong coherent excitation sources. With the inherent advantages of large anti‐Stokes shifts and long excited‐state lifetimes, these Er 3+ –Yb 3+ co‐doped materials can be applied to many areas such as glass system, nanocrystals, silica matrices and oxyfluoride glass ceramic, etc …”