Borate Phosphor

Abstract

Mechanoluminescence (ML) is a type of luminescence observed in solids when it undergoes any kind of deformation or fracture. ML has been observed when the materials undergo friction, bending, stretching, twisting, loading, scratching, crushing, rubbing, cutting and cleaving. The lyoluminescence is observed when a solute irradiated by X-ray or gamma ray get dissolved in a solution. Fifty percent of inorganic materials and nearly one-third of organic materials show mechanoluminescence. But the emission intensity is less. This is the hurdle in designing applications in various fields of applications. Despite this fact, many new areas of applications are exploited by researchers in the last two decades. They include ML and LL multifunctional stress detection and sensing, security, artificial skin, in sports and fitness field etc. This chapter reviews mechanoluminescence and lyoluminescence phenomena in various inorganic materials like alkali halides, aluminates, silicates, borates and organic materials. Borate material has a large bandgap, high luminescence efficiency, high thermal and chemical stability and they are widely used for optical applications. They are the least investigated inorganic materials. Hence, it has a wide scope to study borate materials for ML and LL applications. The mechanoluminescence and lyoluminescence measuring devices are reviewed. Important and new era applications based on ML and LL are discussed. The limitations of ML and LL are reviewed and a future scope has been discussed.