Highly Efficient Bi₂O₂CO₃ Single-Crystal Lamellas with Dominantly Exposed {001} Facets

Abstract

Herein we report the Bi 2 O 2 CO 3 single-crystal nanoplates with dominant {001} exposing facets fabricated via a controllable hydrothermal means. Exposed {001} reactive facets enable BOC-001 nanoplates efficient separation and migration of photoinduced electron−hole pairs, thereby resulting in highly enhanced photoreactivity pertaining to rhodamine B degradation, NO removal, and photocurrent generation. The present work provides a new reference for manipulation of facet-dependent photocatalytic activity of semiconductors. N owadays, semiconductor crystal-facet engineering is very active, which paves a new way for physicochemical property tailoring and the photoactivity enhancement of photocatalysts. 1−5 The successful synthesis of active {001} facets of anatase TiO 2 crystals via HF serving as a capping agent opened the door of research on facet-dependent photocatalytic performance. 6,7 Two-dimensional (2D) bismuth nanomaterials have also drawn considerable attention because their layered crystal configuration can afford an internal driving force promoting the effective separation of photoinduced charge carriers. 8−12 As a typical 2D layered photocatalyst, bismuth oxychloride (BiOCl) gains special interest for facet-controlled manufacture of its single crystal. BiOCl also exhibits facetdependent photocatalytic activity that strongly lies on the dominant exposing facets of the crystal. 13−17 It was disclosed that BiOCl single-crystalline nanosheets with exposed {001} facets enable more efficient separation of photoexcited electron−hole pairs, thus displaying higher photoreactivity than the counterpart with exposed {010} facets. 13 That is to say, the {001} facets are the highly reactive facets in BiOCl.Bismuth carbonate (Bi 2 O 2 CO 3 ), as a newcomer of the "silleń" family that is a kind of bismuth compound composed of [Bi 2 O 2 ] 2+ layers and interlaid halogen ions or anionic groups, also features a 2D layered crystal structure built by [Bi 2 O 2 ] 2+ layers and [CO 3 ] 2− triangles. 18 Lately, we found that Bi 2 O 2 CO 3 exhibits a large nonlinear optical (NLO) effect with strong second-harmonic generation (SHG), which results from its non-centrosymmetrical crystal structure and the aligned arrangement of the [CO 3 ] anionic group. 19 Nevertheless, the property of most concern for Bi 2 O 2 CO 3 is the high photocatalytic performance. 20−29 Zheng etc. first reported the synthesis and photocatalytic activity of Bi 2 O 2 CO 3 samples with different morphologies, 20 including a flower-like sample, sponge-like porous sphere sample, and plate-like sample. Among them, the flower-like Bi 2 O 2 CO 3 exhibits the highest rhodamine B degradation activity. On the basis of the HRTEM results, the flower-like Bi 2 O 2 CO 3 products are considered to be composed of {001}-plane exposed flakes. Thus, the high photocatalytic activity of flower-like Bi 2 O 2 CO 3 was thought to be mainly from the exposed reactive {001} plane of the flakes. Besides, the Bi 2 O 2 CO 3 -based composite photocatalysts also show high photoactivity; e...

Fabrication of Bi2O2CO3/g-C3N4 heterojunctions for efficiently photocatalytic NO in air removal: In-situ self-sacrificial synthesis, characterizations and mechanistic study

“…4d. The single-crystalline nature of BOC in the BOC-CN-160 sample is confirmed by a selected-area electron diffraction (SAED)pattern, which is assigned to the [001] zone-axis diffraction spots of tetragonal BOC[23] (Fig. 4e).…”

“…S1). The compound has been used in medical treatment for a long time and as a photocatalyst in recent years [21,23]. However, Bi 2 O 2 CO 3 photocatalysts can only absorb UV light (less than 5% of the solar light) and exhibit a poor charge carriers separation ability, which seriously restrict the photocatalytic performance of this type photocatalysts.…”

Visible-active photocatalytic behaviors observed in nanostructured lead chalcogenides PbX (X = S, Se, Te)

“…4(b)), which is similar to the photocatalysis of Bi 2 O 2 CO 3 . 37 As previously shown, all of these powder samples presented effective photocatalytic abilities under visible light. To further confirmation, the changes in UV-vis adsorption spectra of Congo red solution under visible light (λ > 420 nm) versus the irradiation time are shown in Fig.…”

Quaternary heterostructured Ag–Bi2O2CO3/Bi3.64Mo0.36O6.55/Bi2MoO6 composite: Synthesis and enhanced visible-light-driven photocatalytic activity

“…This increase may be resulted from the capturing of electrons by the deposited Ag to reduce the recombination of hole-electron pairs [33], whereas the decrease may be related to the blocking of visible light by the over-deposited Ag crystalline [27]. The 2.5% Ag loading sample is possibly at the point of balance, 12 thus exhibiting the highest photocatalytic activity. In this paper, we focus on the photocatalytic properties of It is important to detect the main oxidative species in the photocatalytic process for revealing the photocatalytic mechanism.…”

“…However, despite of some desirable properties of TiO 2 , the most noted disadvantage of TiO 2 is its very low photocatalytic efficiency under visible light irradiation. At the present time, developing visible-light-driven photocatalyst is the most urgent issue in this topic [8][9][10][11][12][13]. And among these works, Bi 2 MoO 6 with a band-gap of about 2.60 eV has been reported to be an active photocatalyst under visible light irradiation and have nowadays attracted considerable attentions [14].…”