Heterogeneous photocatalysis offer many possibilities for finding appropiate environmentally friendly solutions for many of the the problems affecting our society (i.e., energy issues). Researchers are still looking for novel routes to prepare solid photocatalysts able to transform solar into chemical energy more efficiently. In many developing countries, biomass is a major energy source, but currently such countries lack of the technology to sustainably obtain chemicals and/or fuels from it. The Roadmap for Biomass Technologies, authored by 26 leading experts from academia, industry, and government agencies, has predicted a gradual shift back to a carbohydrate-based economy. Biomass and biofuels appear to hold the key to satisfy the basic needs of our societies for the sustainable production of liquid fuels and high value-added chemicals without compromising the scenario of future generations. In this review, we aim to discuss various design routes for nanostructured photocatalytic solid materials in view of their applications in the selective transformation of lignocellulosic biomass to high value-added chemicals.

Chitosan-derived N-doped carbon materials are attractive candidates for the preparation of catalysts with a wide range of applications. Chitosan is a nitrogen rich (∼7 wt %) renewable biomass resource derived from seafood waste. Nitrogen-containing functional groups (amine and acetamide) of chitosan make it a suitable precursor for the synthesis of N-doped carbon materials. This perspective provides an overview on various techniques for the preparation and characterization of chitosan-based N-doped carbon materials and their application in the field of electrocatalysis and photocatalysis. Additional doping with nitrogen imparts greater electrochemical stability and basic character to the material due to the ability of nitrogen atoms to accept electrons. Nevertheless, each type of C–N bonding configuration has unique potential for catalytic reactions attributed to different electronic structure and catalytically active sites. The ability to acquire desired N-bonding states during the process of doping will provide a better control over the material application. The promising performance of chitosan-based N-doped carbon materials in electrocatalytic and photocatalytic reactions is attributed to their improved electronic structure and charge transfer properties. Moreover, research trends toward the design of chitosan-based N-doped carbons materials with required features for electrocatalytic and photocatalytic applications have also been identified.

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