In this work, the optimal conditions of synthesizing and purifying carbon nanotubes (CNTs) from ferrocene were selected at the first stage, where decomposition time, argon fluxes, precursor amounts, decomposition temperature (at 1023 K and 1123 K), and purification process (HNO₃ + H₂SO₄ or HCl + H₂O₂), were modulated through chemical vapor deposition (CVD) and compared to commercial CNTs. The processing temperature at 1123 K and the treatment with HCl + H₂O₂ were key parameters influencing the purity, crystallinity, stability, and optical/electrical properties of bamboo-like morphology CNTs. Selected multiwalled CNTs (MWCNTs), from 1 to 20 wt%, were electropolymerized through in-situ polarization with conductive polymers (CPs), poly(aniline) (PANI) and poly(pyrrole) (PPy), for obtaining composites. In terms of structural stability and electrical properties, MWCNTs obtained by CVD were found to be better than commercial ones for producing CPs composites. The CNTs addition in both polymeric matrixes was of 6.5 wt%. In both systems, crystallinity degree, related to the alignment of PC chains on MWCNTs surface, was improved. Electrical conductivity, in terms of the carrier density and mobility, was adequately enhanced with CVD CNTs, which were even better than the evaluated commercial CNTs. The findings of this study demonstrate that synergistic effects among the hydrogen bonds, stability, and conductivity are better in PANI/MWCNTs than in PPy/MWCNTs composites, which open a promissory route to prepare materials for different technological applications.

Traditionally, biochar is generally proposed to substitute Canadian Sphagnum peat moss. Sugarcane bagasse, filter press mud and sugarcane bagasse ash were mixed in different ratios and proposed as an alternative to substitute commercial Sphagnum peat moss (SPM) for the soilless cultivation of tomato (S. lycopersicum Linnaeus). The choice of the agroindustrial waste ratio was performed from physical-chemical sample characterization. During vegetable production, an adequate ratio was evaluated based on plant height, substrate pH, number of leaves, yield, and fruit size. The addition of essential macro- and micro-nutrients was performed manually. The results show that as-received materials contain different minerals with a structure that corresponds to the quartz, cristobalite, and feldspar phases. A morphology composed of lamellate structures was observed for sugarcane bagasse, whereas the filter press mud and the sugarcane bagasse ash presented compact agglomerates with a surface area of 1.60, 3.78, and 1.07 m² g⁻¹, respectively. The properties of each component promote the water adsorption, retention and releasing capacity. Important differences were observed as the quantity of filter press mud increased, but also it is required an amount of sugarcane bagasse above of 18 wt% to reach a superior performance. This work demonstrated that, in adequate quantities, agroindustrial wastes can be used as a soilless substrate for growing tomatoes in greenhouse, reducing their disposal problems.