Functionalized Nanomaterials for Catalytic Application. Группа авторов

kinetics | pseudo-2^nd-order kinetics [74] Fc-ErGO | EF | 2018 Electrochemical | −1.5 V | (−0.75, −1.0, −1.5, −2.5) V pH (3) | 15 min | pH (7) | 120 Min CIP (99%) | 5 ^·OH | pseudo-1^st-order kinetics [75] FeOCl-CNT | EF | 2020 Thermal-induced | −0.8 V pH (wide) | TC (99.5%) | Fe³⁺/Fe²⁺ | H₂O₂ + ^·OH → H₂O + ^·OOH [76] 3D GA/Ti wire | EF | 2018 Hydrothermal | [0 – (−95.5)] mA cm⁻² pH (2) |120 min EDTA-Ni (m73.2%) | 5 π-π interaction | pseudo-1^st- order kinetics [77]

H-EF system with Fe oxides surrounded by Cu and N on HPC (hollow porous C) as cathodic FeO_x/CuN_xHPC was inferred to give a good degradability for phenol (100%/90 min/variable pH) and (81%/120 min/pH6). Slow redox reaction (Fe²⁺/Fe³⁺) favored e⁻ movement, and formation of ^·OH, that were essentials for degradation in this ambient condition [59]. In a similar fashion a three-layered H-EF catalyst as FMN “CFP@PANI@Fe₃O₄” engineered using electrodeposition-solvothermal method was proven for the removal of 4-NP (100%/60 min/4 runs) at an acidic pH (3) and TOC (51.2%/7 runs) at the same pH [60]. Enrichment of electrocatalytic capacity was attributed to formation of Fe₃O₄ on the functionalized surface of the conducting layers. Wang, Y. et al. fabricated γ-FeOOH GPCA cathodic EF-catalyst for experimenting the degradability of the antibiotic sulfamethoxazole (~90%/5runs). Twelve degraded products by, hydroxylation, isomerization, and oxidation reactions were identified using chromatographic trials [61]. Table 1.1 depicts trials developed by some research personalities.

1.4 Hetero Photo-Fenton as FNMs

Organic effluent’s water management is achieved well, in normal environmental pre-requisites of pH, where the hetero-photo Fenton has a good stability and reusability for notable cycles. Photo-Fenton (PF) catalytic redox reaction may utilize membrane percolation and magnetic purification to effectually decompose OPs into CO₂ and H₂O. Semiconductors, phosphates/oxides/oxyhalides/sulfides/molybdates/tungstates/vanadates of transition and other metals, g-C₃N₄, G, GO, QDs, and MOFs have fascinated the researchers to a larger degree, for probing a simplified and a cost-effective FNMs [78, 79]. Excellent features with required bandgap, got by photo-excitation in an environmentally friendly way, of the materials with notable lattice parametric change, safe guard water system by nanocatalytic action. Figure 1.4 is a graphical representation of FNMs as PF catalyst for water resource management.

Figure 1.4 Functionalized nanomaterials as photo-Fenton catalyst for water resource management.

      1.4.1 Heterogenous-Fentons-Based FNMs

      FNM PAN with EDC as catalyst was used to study the regeneration efficiency of the material in use, by the experimentalist. Further, the regenerated catalytic reaction as heterogenous Fenton (HF) was found to be a better option for degrading RO-16 [80]. Living species vulnerable to the revelation of pharmaceutical organic lteftovers in the water system causing ecological barriers was the point of attack by reporters Wan, Z. et al. [81]. Fe₃O₄-Mn₃O₄/RGO synthesized by polyol and impregnation processes worked well as a HF-like catalyst with the actively formed OH, decomposed SMT (sulfamethazine-drug) (99%/50 min) effectively in a water solvent. Authors Zhou, L. et al., forecasted that the drawbacks due to catalytic reactions can be knocked off by using MPCMSs [82]. C micro-spheres protected Fe₃O₄ NM from oxidation, while degrading MB. Formation of ^·OH supported this HF reaction by H₂O₂ and NH₂OH.

      1.4.2 Photo-Fentons-Based FNMs

Hetero Photo-Fenton (H-PF), an interface between Fenton and photocatalysis, assisted by photon from solar or visible has powerful synergistic properties. PF utilizes the e⁻’s got from the reaction Fe³⁺/Fe²⁺ through oxidation to aid and activate e⁻ transfer to ^·OH from H₂O₂ in the entire redox process. The scavenging radicals contribute to practical utilization in a big factor for protecting water bodies.

      Fe_ox NPs/D3 (diamond NP) that worked well as a H-PF catalyst was effective in degrading and decomposing phenol and H₂O₂, respectively, under an ambient condition. Later, was proved to be a better alternative when in comparison with its analogous as per reports of Espinosa, J.C. et al., where phenol acts as h⁺ quencher and diamond NP as surface releaser of ^·OH favors the optimized reaction [83]. Upgraded new water treatment competencies are scaling up in saving the water resources. For instance, a low-cost valuable functionalized M (magnetite)/PEG/[(FeO (Iron III oxlate)/FeC (Iron III citrate)] showed high catalyst action for a quick disposal and degradation of BPA. Later, the evidenced PF catalyst when on exposing the chosen probe with UV-A light/H₂O₂, had a hierarchical degradation as (M/PEG/FeO) (15 min) > (M/PEG/FeC) > (M/PEG) [84]. In one of their work, a comparative study of MB degrading effect by the synthesized supports of Ni foam (NiF) and Ceramic foam (CM) was done by the authors, whose reports infer that the order of decomposing capacities were: (NiF/TiO₂) > (CM/TiO₂) > (NiF/Bi₂ WO₆) > (CM/Bi₂WO₆). In the same manner, decomposition of Rh B was studied using NF/TiO₂ for PF reactions [85].

      In a different situation, reporters Bui, V.K.H. et al., revealed that Mg-AC (Mg amino-clay) with its versatility and unique characteristic, along with other 2D resources, have fascinated researchers [86]. Hence, Mg-AC finds its place and with a commendable performance in various fields especially in water resources. The resourceful material MgAC-Fe₃O₄/TiO₂ works best for PF catalytic decomposition of MB (93%) (20 min), where ^·OH and ^·O²⁻ formed are promoters for the redox-reaction. Cost-effective and potential approach with Fe-HPAN (carboxyl) functionalized beads developed by researchers was exposed for an effective PF catalytic reaction. Their results showed a better degrading capacity of 99.78% for TOC and 91.68% for p-nitrophenol removal and profitable reutilization was supported by the mesopores present in the FNM [87].

Rice-shaped starch functionalized iron (III)-oxyhydroxide got by green methods using akageneite/goethite had an improved HF and PF catalytic properties obeyed a pseudo-0-order kinetics. FNM was effective in decomposing the OP p-nitrophenol and MO into CO₂ + H₂O to protect the water bodies [88]. In a similar trial, sulfate-functionalized S-Fe₂O₃/TiO₂ NT prepared by solvothermal/impregnation process was proven to be a good candidate for PF catalytic run to discharge the color of X-3B by adopting pseudo-1^st-order kinetics. Notable degradation was observed at pH (4.0) with X-3B (95.7%) lost. Reusability was for four cycles, where ^·OH | ^·OOH played their role for degrading the pollutant [89]. Similarly, reporters Banić, N. et al. inferred that Fe/TiO₂ (TiO₂ as host) as PF catalyst