Perspectivas na utilização de pontos quânticos de carbono sustentável

Abstract

Most of the sewage sludge currently produced in cities is considered a problem when disposing of this material. Its destination still demonstrates inefficient solutions, this residue is usually discarded in landfills, and a small part may be reused in agriculture. Considering that sewage sludge has organic matter in its constitution, an attractive alternative would be its use in carbon nanomaterials. Quantum Carbon Dots (PQCs) are nanomaterials that can be obtained using sewage sludge as a carbon source, enabling the reuse of this large amount of active biomass present in the sludge. The reported applications of this nanomaterial are promising in biosensors, chemical analysis, bioimaging, controlled drug release, photocatalysis, LED and OLED optoelectronic devices, and photovoltaic devices (solar cells). The purpose of this work was to present a literature review on the possibilities of recycling organic waste, mainly sludge, as a raw material for a technological nanomaterial, the PQCs. This chemical transformation would enable the application of these nanomaterials even in OLED devices, using the bases of green chemistry, and reuse their natural carbon fraction, using them as biomass in the production of PQCs. Thus, the literature review was carried out to present historical and conceptual aspects of the PQCs obtained by different residues, indicating types of biomasses that can also be used and indicating which types of characterization are used for the study of obtaining a PQC. The PQCs do not have enough quantum efficiency to replace the PQs in all their applications, such as LEDs and OLEDs. However, with the use of passivating agents and other modifications, therefore, this replacement will be complete.