Green Synthesis of Heterogeneous Visible-Light-Active Photocatalysts: Recent Advances

Alessio Zuliani,Camilla Maria Cova

doi:10.3390/photochem1020009

Abstract

The exploitation of visible-light active photocatalytic materials can potentially change the supply of energy and deeply transform our world, giving access to a carbon neutral society. Currently, most photocatalysts are produced through low-ecofriendly, energy dispersive, and fossil-based synthesis. Over the last few years, research has focused on the development of innovative heterogeneous photocatalysts by the design of sustainable and green synthetic approaches. These strategies range from the use of plant extracts, to the valorization and recycling of metals inside industrial sludges or from the use of solventless techniques to the elaboration of mild-reaction condition synthetic tools. This mini-review highlights progresses in the development of visible-light-active heterogeneous photocatalysts based on two different approaches: the design of sustainable synthetic methodologies and the use of biomass and waste as sources of chemicals embedded in the final photoactive materials.

Highlights

Photochemistry plays a crucial role in the so-defined “Earth green transition”, i.e., the transition towards a climate-neutral economy [1,2]
Lignin-Based Composite Materials for Photocatalysis and Photovoltaics. The purpose of this mini-review is to provide a summary of the most recent insights into the development of innovative photocatalysts by focusing on visible light active materials prepared through the valorization of biomass and waste: as far as we know, a similar review is not present in the literature
This work describes, in two separate sections, photocatalysts produced via sustainable processes and photocatalysts produced by englobing in the final product biomass or waste materials

Summary

Introduction

Photochemistry plays a crucial role in the so-defined “Earth green transition”, i.e., the transition towards a climate-neutral economy [1,2]. It should be noted that, similar to the use of fossil fuels, the use of biomass consists of exploiting solar energy already converted into chemical bonds by the action of chlorophyll, i.e., nature’s photocatalyst, but in the form of renewable and carbon neutral resources. Green synthesis: Photocatalytic degradation of textile dyes using metal and metal oxide nanoparticles-latest trends and advancements [22] The purpose of this mini-review is to provide a summary of the most recent insights into the development of innovative photocatalysts by focusing on visible light active materials prepared through the valorization of biomass and waste: as far as we know, a similar review is not present in the literature. This work describes, in two separate sections, photocatalysts produced via sustainable processes (i.e., focusing on the synthetic steps) and photocatalysts produced by englobing in the final product biomass or waste materials (i.e., using them as sources of chemicals)

A Green Synthetic Approach

Titanium Dioxide-Based Photocatalsyts

A Focus on Materials

Summary and Outlook