Microwave synthesis of BiPO4 nanostructures and their morphology-dependent photocatalytic performances

Solvothermal synthesis and characterization of hierarchical spindle-like BiPO4aggregates

“…As a crystalline semiconductor, the optical aborption near the band edge is based on the equation ĮhȞ=A(hȞ-Eg) 1/2 (where Į is the absorption coefficient, A is a constant, hȞ is the photo energy, and Eg is the bandgap energy). From the curve of the (ĮhȞ) 2 vs. photo energy (hȞ), the bandgap energy of the spindle-like BiPO 4 aggregates is estimated to be 3.46 eV, slightly lower than or similar to those of BiPO 4 materials reported previously [13][14][15][16][17][18][19][20].…”

“…Based on the experimental results, the probable formation mechanism of the spindle-like BiPO 4 aggregates may be ascribed to an oriented aggregation process in our current experiment. First, Bi(NO 3 ) 3 could alcoholyze and hydrolyze in EG and water to form a bismuth oxide hydroxide nitrate complex which might be in the form of [Bi 6 O 5 (OH) 3 ](NO 3 ) 5 and then Bi 3+ was generated at a release speed by the dissociation of the complex [14,19]. Meanwhile, PO 4 3-ions were also provided by gradual dissociation of STPP in EG/water system.…”

“…In addition, BiPO 4 was reported to be an excellent host for rare-earth ions that can yield luminescence and a novel photocatalyst for degrading organic dyes [7,10]. Up to now, BiPO 4 micro/nanomaterials with different morphologies have been synthesized such as nanoparticles [11,12], nanorods [13][14][15][16][17][18] and hierarchical architectures [19,20]. To obtain such micro/nanomaterials, a variety of methods including chemical vapor deposition21, sonochemical method [13,22], microwave irradiation [19], electrochemical deposition [15], hydrothermal/solvothermal treatment [14,18,23,24] have been employed.…”

“…Up to now, BiPO 4 micro/nanomaterials with different morphologies have been synthesized such as nanoparticles [11,12], nanorods [13][14][15][16][17][18] and hierarchical architectures [19,20]. To obtain such micro/nanomaterials, a variety of methods including chemical vapor deposition21, sonochemical method [13,22], microwave irradiation [19], electrochemical deposition [15], hydrothermal/solvothermal treatment [14,18,23,24] have been employed. In spite of a few approaches developed to fabricate BiPO 4 hierarchical micro/nanostructures, which followed complicated and tedious experimental procedure and might cause pollution, a facile synthesis of BiPO 4 hierarchical architectures is still an ongoing challenge.…”

Synthesis of Surface Oxygen-deficient BiPO4 Nanocubes with Enhanced Visible Light Induced Photocatalytic Activity

“…In addition, n is determined by the type of optical transition of a semiconductor (n = 1 for a direct transition and n = 4 for an indirect transition). As BiPO 4 exhibits the characteristic of indirect band transition 26 , the value of n is 4. The corresponding Eg values of WBiPO 4 and GBiPO 4 were determined from a plot of (ahv) 2 versus energy (hv) ( Figure.…”