Phase modified ferroelectricity in Na0.5-xKxBi0.5TiO3

Solvothermal synthesis of (Na0.8K0.2)0.5Bi0.5TiO3 piezoelectric catalyst with morphotropic-phase-boundary structure for efficient dye degradation

“…1b and c, with the increase of x value, the splitting peak at around 39.8° gradually disappears while the splitting peak at around 46.2° becomes more prominent, indicating a gradual transformation of the phase structure. 31 All diffraction peaks gradually shift towards lower angles, confirming the formation of a binary solid solution system in which K + has successfully dissolved into the BNT crystal lattice. As K + ( r = 1.33 Å) has a larger radius than Na + ( r = 0.95 Å), the relatively large K + occupies the originally small Na + site in the A-site of the crystal lattice.…”

“…1d and e show the Rietveld refinement patterns of the x = 0.2 sample, which were well fitted using the dual-phase symmetric model of R3m + P4mm, confirming that the (Na 0.8 K 0.2 ) 0.5 Bi 0.5 TiO 3 piezoelectric material is a binary solid solution of a rhombohedral ( R 3 m ) and tetragonal ( P 4 mm ) mixed phase. 31…”

“…29,30 Another characteristic of BNT is its high compatibility with various elements, where introducing different metal cations into the A or B site forms a solid solution, an effective way to improve its piezoelectric properties. 31,32…”

“…29,30 Another characteristic of BNT is its high compatibility with various elements, where introducing different metal cations into the A or B site forms a solid solution, an effective way to improve its piezoelectric properties. 31,32 The literature reports that most of the BNT-based piezoelectric catalysts are prepared by traditional solid-phase methods. On the one hand, pure BNT powders prepared by solid-phase reactions have disadvantages such as high electrical conductivity and harsh polarization conditions, which severely limit their application in the catalysis field.…”

Interfacial engineering of CuWO4/WO3 thin films precisely fabricated by ultrasonic spray pyrolysis for improved solar water splitting

“…28 A suitable energy band structure and similar chemical composition are preferable for constructing a heterojunction. Among the potential semiconductors for paring with CuWO 4 , WO 3 is one of the optimal ones due to the following merits: (1) the close chemical composition ensures good compatibility with CuWO 4 ; 29 (2) WO 3 shows an intrinsic long hole diffusion length and high mobility; 30,31 (3) the bandgap of WO 3 matches well with that of CuWO 4 because of the similar conduction band contributed by W 5d and the slightly different valence band position; 32 (4) the well-matched lattice parameter with CuWO 4 is favorable for establishing stable interfaces with a strong built-in electric field, enabling improved photogenerated charge separation and transfer (see discussion below). 33 Although there were several reports for the construction of the CuWO 4 /WO 3 heterojunction, [34][35][36][37] the underlying molecular mechanism for improved electrocatalytic PEC performance is still unclear and needs to be further clarified.…”