Lignin-metal oxide composite for photocatalysis and photovoltaics

Metal oxides have an excellent capacity to generate charge carriers in response to energy or light irradiation because of their promising electronic structural arrangement. So, the use of semiconductor oxides has been proven very functional in photocatalysis and photovoltaic technologies for years. The concept of these light-responsive metal-oxide-based polymer composites to provide combining advantages of organic and inorganic compounds is also being under research in recent past. Lignin, as a cheap, abundant, biocompatible, and renewable polymer, can be successfully utilized as a photocatalyst support in potential photodegradation application and as an anodic polymer dopant of semiconductor type in photovoltaic cells with enhanced photoconversion efficiency of solar cells and electronic devices. Porosity of lignin accelerates the development of number of lignin-based metal oxide composites of varying particle sizes, crystal architectures, surface modifications, etc., following different fabrication methods for their potent usage in the arena of photocatalysis and photovoltaics. These lignin-metal oxide composites should be ecologically affable and fabricated via inexpensive routes. This chapter will give a detailed review on lignin source, extraction, characterization, application along with lignin-based composites of metal oxide preparation techniques, and their evaluation in photocatalysis and photovoltaics.