The global water crisis requires effective wastewater treatment methods where conventional approaches often face challenges related to cost, recyclability, efficiency, and overall effectiveness. In this regard, the significantly small size, large surface area, and enhanced photocatalytic properties of recently developed nanoparticles have opened new avenues for wastewater treatment. This comprehensive review focuses on recent advancements in the synthesis methods for different types of nanoparticles and nanocomposites based on metals, carbon, polymers, waste materials, and zeolites which have highly sustainable and innovative results in wastewater treatment. The introduction of silver and gold nanoparticles has enhanced photocatalytic and biological activities. Similarly, zeolite and seaweed composites have exhibited efficient dye degradation capabilities. Eco-friendly carbon soot nanoparticles have shown promising biological activities, while nitrogen-doped carbon quantum dots have exhibited long-term stability for various applications. Additionally, waste material-based calcium oxide nanoparticles and carbon quantum dot-carbon nanotube nanocomposites have also shown enhanced dye degradation activities.

The world surrounded by plastics generates a lot of uncertainty and the first victims are sea animals, plastic in contact with the sun is able to disintegrate and generate toxins that are harmful to health. It is for this reason that this research in bibliographic review allows us to know the different solutions to counteract microplastics through the analysis of the Scopus database and the VOSviewer tool that allows us to analyze the data, considering the essential characteristics that are plants, animals, bacteria, algae and technologies that allow the disintegration, elimination and purification of microplastics, graphs and tables were obtained which allow us to recognize the analyzed data, the countries that carry out these investigations and the bibliometric maps worldwide. The results allow us to understand that the existence of microplastics generates many negative consequences for planet earth, however, there are different solutions which we can use and apply to counteract these microplastics, also considering that countries like Peru do not find published scientific research relevant to this matter. The purpose of this research is to allow us to make better decisions and not lose heart in the face of microplastics since it can be fought with the different solutions that we find on planet earth, technology and the other objective is to motivate readers to take action in the issue and allow generating change in the use of plastics.