Piezoelectric generators enable maintenance‐free power supply for integrated electronics in smart system applications. The majority of publications consider the aspect of power transfer electronics; however, the influence of the transducer materials was rarely described. Recently, material characteristics received increased attention from the ceramics community. We set the focus of the present paper to commercially available piezoelectric ceramics. Different figures of merit are derived from system analysis using electromechanical modeling. They allow for the description of typical load scenarios and commercial piezoceramics. Derived rules are expected to be helpful for guiding ceramic engineers and system designers to succeed in improved generator solutions.

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An emerging demand for the precise manipulation of cells and particles for applications in cell biology and analytical chemistry has driven rapid development of ultrasonic manipulation technology. Compared to the other manipulation technologies, such as magnetic tweezing, dielectrophoresis and optical tweezing, ultrasonic manipulation has shown potential in a variety of applications, with its advantages of versatile, inexpensive and easy integration into microfluidic systems, maintenance of cell viability, and generation of sufficient forces to handle particles, cells and their agglomerates. This article briefly reviews current practice and reports our development of various ultrasonic standing wave manipulation devices, including simple devices integrated with high frequency (>20 MHz) ultrasonic transducers for the investigation of biological cells and complex ultrasonic transducer array systems to explore the feasibility of electronically controlled 2-D and 3-D manipulation. Piezoelectric and passive materials, fabrication techniques, characterization methods and possible applications are discussed. The behavior and performance of the devices have been investigated and predicted with computer simulations, and verified experimentally. Issues met during development are highlighted and discussed. To assist long term practical adoption, approaches to low-cost, wafer level batch-production and commercialization potential are also addressed.

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