Fig. 6.

a SEM image of Sn deposited on the c⁺ domain from SnCl₂ solution. The surface of the c⁻ domain was unaffected by the photoexcitation. Reproduced with permission [179]. Copyright 2008, American Chemical Society. b A typical PFM image of the poled pattern. Brighter squares in the picture are positive domains and the dark squares are negative domains; surrounding region is an unpoled area. Reproduced with permission [77]. Copyright 2009, Elsevier. c Topographic AFM images of a 15-nm-thick TiO₂ film surface after reaction with silver nitrate solution and after reaction in lead acetate solution. Reproduced with permission [74]. Copyright 2010, American Chemical Society. d H₂ concentration measured as a function of oscillating time of a piezoelectric beam in deionized water at a frequency of 10 Hz (triangles) and 20 Hz (diamonds). A Si cantilever with identical configuration was used as a control (circles). Reproduced with permission [65]. Copyright 2008, Wiley-VCH. e The piezo-catalytic hydrogen production from water splitting under vibration by BFO nanosheets at different vibration frequencies, and with different mechanical powers. Reproduced with permission [71]. Copyright 2019, Wiley-VCH. f Rate coefficients of the BHS in degradation of MO and corresponding H₂ evolution rates. Reproduced with permission [69]. Copyright 2015, American Chemical Society