Abstract
Nitrophenol is common carcinogenic pollutant known for its adverse effects on human beings and aquatic life. During the last few decades, the chemical reduction of nitrophenol compounds has been widely reported as the advanced removal methodology for such hazardous dyes from aqueous reservoirs. Many researchers have utilized different nanocatalytic systems using sodium borohydride (NaBH4) as the reducing agent for acquiring industrially useful reduction product of aminophenol by carrying out the chemical reduction of nitrophenols. Polymeric material supported monometallic nanoparticles are widely reported catalyst for the degradation of 2-nitrophenol (2-NP) and 4-nitrophenol (4-NP). This review critically discusses the pros and cons of numerous supporting mediums of nanocatalytic assemblies used for the immobilization of nanomaterials. Mechanism and kinetic analysis of the reduction reaction of 2-NP and 4-NP have also been explained in this study. In addition, recent literature has also been effectively summarized in the tabular form for developing a better understanding of the reader. Pictorial representation of key nanocatalytic assemblies and catalytic reduction mechanism has also been narrated in this study.
Graphical abstract
Abbreviations
NIPAM | = | N-isopropylacrylamide |
MAA | = | Methacrylic acid |
AAm | = | Acrylamide |
HEMA | = | 2-Hydroxyethyl methacrylic acid |
MAAc | = | Methacrylic acid |
DMAEMA | = | N,N dimethylaminoethyl methacrylate |
p(AMAm) | = | Poly(amido amine) |
PMMA | = | Poly(methyl methacrylate) |
PEG | = | Poly(ethylene glycol) |
PEI | = | Block-linear polyethylenimine |
PCL | = | Block-poly(ε-caprolactone) |
AAc | = | Acrylic acid |
AMPS | = | 2-Acrylamido-2-methyl-1-propanesulfonic acid |
PDMAEMA | = | Poly(2-(dimethylamino) ethyl methacrylate) |
p(AMPS) | = | Poly(2-acrylamido-2-methyl-1-propansulfonic acid) |
4VP | = | 4-Vinyl pyridine |
p(VPA) | = | Polyvinyl phosphonic acid |
AAEM | = | Acetoacetoxyethyl methacrylate |
HAuCl4 | = | Tetrachloroauric acid |
VCL | = | N-vinylcaprolactam |
CPL | = | Coploymer ligand |
CTAB | = | Cetyl trimethylammoniumbromide |
SPB | = | Spherical polyelectrolyte brushes |
NR@SiO2 | = | Porous silica-coated gold nanorods |
SiO2 | = | Silica |
Al2O3 | = | Alumina |
NaBH4 | = | Sodium borohydride |
= | Borohydride | |
GO | = | Graphene oxide |
RGO | = | Reduced graphene oxide |
4-NP | = | 4-Nitrophenol |
2-NP | = | 2-Nitrophenol |
4-AP | = | 4-Aminophenol |
2-AP | = | 2-Aminophenol |
AgNPs | = | Silver nanoparticles |
MNPs | = | Metal nanoparticles |
bi-MNPs | = | Bimetallic nanoparticles |
Pd NPs | = | Palladium nanoparticles |
Fe3O4 | = | Iron oxide |
Ni NPs | = | Nickel nanoparticles |
Au NPs | = | Gold nanoparticles |
Pt NPs | = | Platinum nanoparticles |
Co NPs | = | Cobalt nanoparticles |
NRs | = | Nanorods |
NS | = | Nanospheres |
NCs | = | Nanoclusters |
kapp | = | Apparent rate constant |
IT | = | Induction time |
MNPs | = | Metal nanoparticles |
PMAM | = | Poly(amidoamine) |
P | = | Phosphorous |
Ag | = | Silver |
Au | = | Gold |
Pt | = | Platinum |
Pd | = | Palladium |
Cu | = | Copper |
Co | = | Cobalt |
Ni | = | Nickel |
PPy | = | Polypyrrole |
ND | = | Nanodiamond |
L-H | = | Langmuir–Hinshelwood |
Conflict of interest
The authors declare no conflicts of interest.