Traps in the spotlight: How traps affect the charge carrier dynamics in Cs₂AgBiBr₆ perovskite

Suitable optoelectronic properties of lead halide perovskites make these materials interesting semiconductors for many applications. Toxic lead can be substituted by combining monovalent and trivalent cations, such as in Cs₂AgBiBr₆. However, efficiencies of Cs₂AgBiBr₆-based photovoltaics are still...

Optimization of scale-up of KNLN piezocomposites: for flexible haptic feedback applications

In this thesis, we focus on flexible haptic feedback applications which rely on the sensation of touch to display a feedback to the user that establishes a system to user interaction. Piezocomposites made of piezoceramic and polymer phases can be used here due to their high flexibility and piezoelectric properties that enable them to deform...

Flexible Lead-Free Piezoelectric Composite Materials for Energy Harvesting Applications

Vibrational piezoelectric energy harvesters are being investigated to replace batteries in embedded sensor systems. The energy density that can be harvested depends on the figure of merit, d₃₃g₃₃, where d₃₃ and g₃₃ are the piezoelectric charge and voltage coefficient. Commonly used piezoelectric...

Enhancing energy harvesting potential of (K,Na,Li)NbO₃-epoxy composites via Li substitution

In this study, the influence of Li substitution on the piezoelectric performance of lead-free K_0.5Na_0.5NbO₃ (KNN)-epoxy composites is explored. KNN piezoceramic particles modified with 0-12 mol% of Li are prepared via a double calcination technique, resulting in a perovskite particulate which transitions from...

Highly Flexible lead-free piezoelectric composites- For vibration damping and noise cancellation application

Vibrations are inherent part in an aircraft system and supressing them has always been a technological challenge. Over the recent years, damping of mechanical vibrations is becoming increasing important to improve the reliability and performance of the aircraft systems and also increase the safety of passengers. As a response to these issues,...

Explorative study into the sustainable use and substitution of soldering metals in electronics: Ecological and economical consequences of the ban of lead in electronics and lessons to be learned for the future

The Directive 2002/95/EC (RoHS Directive), among other substances, bans the use of lead in the electrical and electronics industry. This explorative study assesses the worldwide environmental and economical effects of the substitution of lead in solders and finishes. It shows the worldwide additional cost of lead-free soldering compared to...