Synergistic Effects Of Zinc Oxide Research Articles

Synergistic enhancement of maize crop yield and nutrient assimilation via zinc oxide nanoparticles and phosphorus fertilization.

Low recovery of conventional fertilizers remains a significant bottleneck for maize production globally. In particular, with phosphate fertilization, zinc (Zn) is prone to precipitation in soil, reducing recovery of both phosphorus (P) and Zn by maize. The present study was designed to investigate the synergistic effect of zinc oxide (ZnO) nanoparticles (NPs) and P on maize crop growth, yield, and nutrient uptake under ZnO seed coating and foliar application in a randomized complete block design. However, plants were subjected to two ZnO NPs levels (0.5 and 12 kg ha-1) amended with two P levels (45 and 90 kg ha-1). ZnO NPs, especially in the form of foliar application, with a P dose of 90 Kg ha-1 significantly (P < 0.05) improved maize crop growth, yield, and nutrient uptake compared with control. In comparison with the control group, plants grown in these conditions absorbed higher levels of Zn and P. Zn uptake rose to 16.34 g ha-1, 137.88 g ha-1, and 166.89 g ha-1 in roots, grains, and stover respectively, and P uptake increased to 0.80 mg kg-1, 10.066 mg kg-1, and 12.17 mg kg-1 respectively. Additionally, seed emergence rate, plant height, and cob length increased by up to 2%, 1177 cm2, and 3.3 cm respectively compared with control. Furthermore, Zn use efficiency was increased up to 38.55% in ZnO NPs foliar application. Application of ZnO NPs at 0.5 kg ha-1 in the form of foliar application with 90 kg ha-1 P dose produced a more pronounced increment in the parameters studied than ZnO NPs seed coating did. © 2024 Society of Chemical Industry.

Antibacterial and Cytotoxic Effects of Biosynthesized Zinc Oxide and Titanium Dioxide Nanoparticles.

Nanotechnology is a rapidly developing field of research that studies materials having dimensions of less than 100 nanometers. It is applicable in many areas of life sciences and medicine including skin care and personal hygiene, as these materials are the essential components of various cosmetics and sunscreens. The aim of the present study was to synthesize Zinc oxide (ZnO) and Titanium dioxide (TiO2) nanoparticles (NPs) by using Calotropis procera (C. procera) leaf extract. Green synthesized NPs were characterized by UV spectroscopy, Fourier transform infrared (FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM) to investigate their structure, size, and physical properties. The antibacterial and synergistic effects of ZnO and TiO2 NPs along with antibiotics were also observed against bacterial isolates. The antioxidant activity of synthesized NPs was analyzed by their α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity. In vivo toxic effects of the synthesized NPs were evaluated in albino mice at different doses (100, 200, and 300 mg/kg body weight) of ZnO and TiO2 NPs administered orally for 7, 14, and 21 days. The antibacterial results showed that the zone of inhibition (ZOI) was increased in a concentration-dependent manner. Among the bacterial strains, Staphylococcus aureus showed the highest ZOI, i.e., 17 and 14 mm against ZnO and TiO2 NPs, respectively, while Escherichia coli showed the lowest ZOI, i.e., 12 and 10 mm, respectively. Therefore, ZnO NPs are potent antibacterial agents compared to TiO2 NPs. Both NPs showed synergistic effects with antibiotics (ciprofloxacin and imipenem). Moreover, the DPPH activity showed that ZnO and TiO2 NPs have significantly (p > 0.05) higher antioxidant activity, i.e., 53% and 58.7%, respectively, which indicated that TiO2 has good antioxidant potential compared to ZnO NPs. However, the histological changes after exposure to different doses of ZnO and TiO2 NPs showed toxicity-related changes in the structure of the kidney compared to the control group. The current study provided valuable information about the antibacterial, antioxidant, and toxicity impacts of green synthesized ZnO and TiO2 NPs, which can be influential in the further study of their eco-toxicological effects.

Self-Healing and Shape Memory Behavior of Functionalized Polyethylene Elastomer Modified by Zinc Oxide and Stearic Acid

There is still a great need to develop self-healing polymers (SHPs) using a cost-effective modification approach for commercial polymers. Herein, we describe our preparation of self-healing (SH), acrylic acid-functionalized, metallocene polyethylene elastomer (mPE-g-AA) composites containing ZnO and stearic acid (SA) that feature both supramolecular hydrogen bonding and ionic interactions. Regarding mechanical properties, with the addition of various contents of ZnO/SA in the mPE-g-AA matrix, their tensile strength increased to be higher than that of mPE-g-AA. As for the shape memory properties, with this synergistic effect of zinc oxide (ZnO), SA, and grafting AA, both the shape fixing ratio and shape recovery ratio of those functionalized polyethylene samples modified by ZnO and SA increased up to above 80% as a result of the hydrogen bonding and reversible ionic crosslinked networks acting as physical crosslinks. Among all of the samples, mPE-g-AA/ZnO 4/SA 1 (4 phr of ZnO and 1 phr of SA) exhibited the highest SH efficiency, at 44.6% for half-hour healing and up to 64.4% under 6 h healing, being higher than those related self-healing mPE studies in the literature. These hydrogen bonded reversible networks, along with the enhanced molecular flow at high temperatures in addition to ionic interactions, could also have a great potential in self-healing applications, besides the shape memory performance. So far, to the authors’ best knowledge, there have been no published reports of the design of polyolefin elastomers with thermally-triggered shape memory effect by adding ZnO to assist the self-healing behavior. The current synergistic approach paves the way for preparing various SH commercial polymers where surface scratches and cuts have previously been hard to repair.

Synergistic effects of zinc oxide coupled copper hexacyanoferrate nanocomposite: Robust visible-light driven dye degradation

Synthetic dyes are known to be toxic and endocrine disruptors. Therefore, advance and fast processes based on low-cost and highly proficient nanomaterials are required for their elimination. Herein, zinc oxide coupled copper hexacyanoferrate (ZnO-CuHCF) nanocomposite was prepared using plant extract of Azadirachta indica. Nanocomposite was characterized throughspectroscopic and electron microscopic techniques. Distorted cubic nanocomposite with particle size range of 50–100 nm was obtained and appearance of stretching vibration around 483 cm−1 confirmed the bonding of O of ZnO and Cu of CuHCF to form ZnO-CuHCF. Subsequently, nanocomposite was utilized as photocatalyst for removal of selected dyes under sunlight. At moderate dosage and neutral pH, nanocomposites was found highly active for quantitative degradation (97–99%) of Eriochrome Black T (EBT) and of Rhodamine B (RB) within 3 h of sunlight exposure. Photodegradation of dyes by nanocomposite was consisting of initial Langmuir adsorption followed by first order kinetics. Comparative to natives, nanocomposite was more capable and lowered the t1/2 value of EBT (0.6 h) and RB (0.9 h) to a greater extent. The findings were attributed to higher surface area (95 m2 g−1) and particle stability (zeta potential: −40.4 mV) of nanocomposite as well as synergistic effects of parent materials. Mechanism of the photo-catalysis was investigated by using radical scavenger and understanding the steps involved in removal process. Applicability of the nanocomposite for almost ten cycles of dye removal ensures its stability and excellent catalytic efficiency. Overall, present work provides an effective and sustainable photocatalyst having worth of industrial applications.

Space Charge Characteristics and Electrical Properties of Micro-Nano ZnO/LDPE Composites

The synergistic effects of zinc oxide (ZnO) Micro/Nano particles simultaneously filled in low-density polyethylene (LDPE) on the space charge characteristics and electrical properties has been investigated by melt blending micro-scale and nanoscale ZnO additive particles into LDPE matrix to prepare Micro-ZnO, Nano-ZnO, and Micro-Nano ZnO/LDPE composites. The morphological structures of composite samples are characterized by Polarizing Light Microscopy (PLM), and the space charge accumulations and insulation performances are correlated in the analyses with Pulse Electronic Acoustic (PEA), DC breakdown field strength, and conductance tests. It is indicated that both the micro and nano ZnO fillers can introduce plenty of heterogeneous nuclei into the LDPE matrix so as to impede the LDPE spherocrystal growth and regularize the crystalline grains in neatly-arranged morphology. By filling microparticles together with nanoparticles of ZnO additives, the space charge accumulations are significantly inhibited under an applied DC voltage and the minimum initial residual charges with the slowest charge decaying rate have been achieved after an electrode short connection. While the micro-nano ZnO/LDPE composites acquire the lowest conductivity, the breakdown strengths of the ZnO/LDPE nanocomposite and micro-nano composite are, respectively, 13.7% and 3.4% higher than that of the neat LDPE material.

Synergistic effects of zinc oxide in montmorillonite flame‐retardant polystyrene nanocomposites

ABSTRACTIn this study, two‐dimensional organic montmorillonite (OMMT) and one‐dimensional needlelike ZnO were used as flame retardants of polystyrene (PS). Polystyrene/organic montmorillonite (PMT) and polystyrene/organic montmorillonite/zinc oxide nanocomposites (PMZs) with different weight ratios were prepared by melt intercalation. Information on the morphologies and structures of the PS nanocomposites was obtained with Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results indicate that a mixed exfoliated–intercalated structure was observed in the PMT and PMZs. Dynamic mechanical thermal analysis showed that both the storage modulus and glass‐transition temperature values of the PMT and PMZs were significantly improved compared with those of the neat PS. The mechanical property tests showed that the bending modulus values of both PM5 (PS/OMMT weight ratio = 95:5) and PMZs increased compared with that of pristine PS. PMZ1 (PS/OMMT/ZnO weight ratio = 94:5:1) provided no decrease in the tensile strength in comparison with PS. A synergistic effect was observed between OMMT and ZnO; this resulted in improvements in the flame retardancy and dynamic mechanical properties in the PMZs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43047.

The synergistic effect of zinc oxide and phenylphosphonic acid zinc salt on the crystallization behavior of poly (lactic acid)

In order to improve the crystallinity and crystallization rate of poly (lactic acid) (PLA), a method for the preparation of a composite nucleating agent (CNA) consisting of zinc oxide and phenylphosphonic acid zinc salt was proposed. Zinc oxide, phenylphosphonic acid zinc salt and CNA were mixed into PLA through the melt blending method, respectively. The resultant PLA samples were characterized by differential scan calorimeter (DSC) and polarized optical microscope (POM). The DSC results showed that the crystallinity and crystallization temperature of the PLA samples with CNA were higher than those of the other PLA samples. The phenomena of crystallization nucleation and growth of various PLA samples were observed by means of POM. Isothermal and non-isothermal crystallization behavior of various PLA samples with different addition of CNA was studied, the corresponding result showed that the overall crystallinity, crystallization rate, nucleation density, and spherulite number increased obviously, as well as the crystallization time decreased, indicating the heterogeneous nucleating effect of CNA on the crystallization of PLA. For each of the component of CNA, the phenylphosphonic acid zinc salt could be used as an effective site of heterogeneous nucleation, resulting in the increasing nucleation density of PLA, and the zinc oxide could be acted as a good crystallization promoter for promoting the crystal growth of PLA. At the CNA content of 1 phr, CNA had a significant impact on crystallization behavior of PLA with a little negative influence on the molecular weight of PLA.

Effect of zinc oxide on properties of phenolic foams/halogen‐free flame retardant system

ABSTRACTA halogen‐free flame retardant system consisting of ammonium polyphosphate (APP) as an acid source, blowing agent, pentaerythritol (PER) as a carbonific agent and zinc oxide (ZnO) as a synergistic agent, was used in this work to enhance flame retardancy of phenolic foams. ZnO was incorporated into flame retardant formulation at different concentrations to investigate the flammability of flame retardant composite phenolic foams (FRCPFs). The synergistic effects of ZnO on FRCPFs were evaluated by limited oxygen index (LOI), thermogravimetric analysis (TGA), cone calorimeter tests, and images of residues. Results showed that the flame retardant significantly increased the LOI of FRCPFs. Compared with PF, heat release rate (HRR), total heat release (THR), effective heat of combustion (EHC), production or yield of carbon monoxide (COP or COY) and Oxygen consumption (O2C) of FRCPFs all remarkably decreased. However specific extinction area (SEA) and total smoke release (TSR) significantly increased, which agreed with the gas‐phase flame retardancy mechanism of the flame retardant system. The results indicated that FRCPFs have excellent fire‐retardant performance and less smoke release. And the bending and compression strength were decreased gradually with the increase of ZnO. The comprehensive properties of FRCPFs were better when the amount of ZnO was 1∼1.5%. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42730.

Synergistic effects of zinc oxide in intumescent flame retardant silicone rubber composites

The synergistic effects of zinc oxide (ZnO) with intumescent flame retardant (IFR; based on phosphorus acid, melamine and pentaerythritol) in silicone rubber (SR) composites have been studied using limiting oxygen index, UL-94, cone calorimeter test and digital photographs. The results showed that 2·0 wt-% loading ZnO in the flame retardant SR composites could greatly reduce the peak values of heat release rate and smoke production rate, and form a compact char layer on the surface of the sample. Thus, a suitable amount of ZnO plays a synergistic effect with IFR in flame retardant SR composites system.

Synergistic effect of zinc oxide on the flame retardant and thermal properties of acrylonitrile–butadiene–styrene/poly(ethylene terephthalate)/ammonium polyphosphate systems

AbstractThe influence of micrometeric zinc oxide (micro‐ZnO) and nanostructured zinc oxide (nano‐ZnO) on the flammability and thermal properties of acrylonitrile–butadiene–styrene (ABS)/poly(ethylene terephthalate) (PET)/ammonium polyphosphate (APP) systems was investigated. When 1 wt % micro‐ZnO (or nano‐ZnO) was incorporated into the ABS/PET/APP systems, the best flame‐retardancy rating of V0 was achieved during UL94 tests, and the limiting oxygen index value was 31 (or 30). The thermogravimetric analysis indicated that the addition of zinc oxide (ZnO) improved the thermal stability and the yield of char residues of the ABS/PET/APP systems. Fourier transform infrared spectrophotometry showed that ZnO improved the efficiency of APP, and the char residues of the ABS/PET/APP + 2 wt % ZnO systems had higher phosphorus contents. Scanning electron microscopy showed that the surface of the char for ABS/PET/APP + 2 wt % micro‐ZnO (or nano‐ZnO) improved significantly with a cohesive and dense structure; however, that for ABS/PET/APP + 5 wt % micro‐ZnO (or nano‐ZnO) exhibited a looser char layer with bigger holes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.

Synergistic Effects of Zinc Oxide on Intumescent Flame-Retarded Polypropylene Composites

The melamine phosphate (MP) was synthesized from melamine and phosphate acid. Zinc oxide (ZnO) was used as a synergistic agent by adding into the MP during the synthesis process. The reaction products were characterized by Fourier transform infrared spectroscopy (FTIR). The properties of polypropylene (PP) composites containing intumescent flame retardant (IFR) additives of melamine phosphate and pentaerythritol (PER) were investigated by the limiting oxygen index (LOI), UL-94 vertical burning test, thermogravimetric analysis (TG) and scanning electron microscopy (SEM). The results indicated that the LOI value of the composites could be enhanced obviously with suitable content of ZnO. When the ZnO content was 6 wt% in MP, the LOI value reached 34.1%, which showed 10% higher than that of the composites without ZnO.

Synergistic effects of zinc oxide with layered double hydroxides in EVA/LDH composites

The synergistic effects of zinc oxide (ZnO) with layered double hydroxides (LDH) in ethylene vinyl acetate copolymer/LDH (EVA/LDH) composites have been studied using thermal analysis (TG), limiting oxygen index (LOI), UL-94 tests, and cone calorimeter test (CCT). The results from the UL-94 tests show that the ZnO can also act as flame retardant synergistic agents in the EVA/LDH composites. The CCT data indicated that the addition of ZnO in EVA/LDH system can greatly reduce the heat release rate. The TG data show that the ZnO can increase the thermal degradation temperature and the charred residues after burning.