Amardeep StarChild | Panjab University, Chandigarh(India) (original) (raw)

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Papers by Amardeep StarChild

It has been universally delineated that the plasmonic metal nanoparticles can enhance the efficie... more It has been universally delineated that the plasmonic metal nanoparticles can enhance the efficiency of photovoltaic cell by increasing the probability of energetic solar photons capturing phenomena using localized surface plasmonic resonance response. In this paper, we developed a novel in-situ simple approach to synthesize noble plasmonic silver nanoparticles (AgNP) from aqueous poly-vinyl-pyrrolidone solution of metal salt using radiolysis of water via synchrotron monochromatic X-ray irradiation without any chemical reducing agent. X-ray irradiation of water produces hydrated electrons e () aq − , superoxide O () 2 − and atom radicals H • , which triggers the reaction and reduces metal salt. X-ray radiolysis based synthesis provides the control over the reaction and prevent the formation of secondary products as occurs in case of chemical reduction route. In the previous studies, synchrotron " white " X-rays had been examined for the synthesis of metal nanoparticles, but that technique limits only upto the material synthesis while in this work we explored the role of " monochromatic " X-rays for the production of bulk amount of nanoparticles which would also provide the feasibility of in-situ characterization. Transmission electron micrographs show that the synthesized AgNP appears spherical with diameter of 2–6 nm and is in agreement with the size estimation from uv-vis spectra by " Mie theory ". Plasmonic metal nanoparticles are of great interest in the field of green energy especially solar cell industry 1. They build the foundation for enhanced light trapping in the device via their unique localized surface plasmon resonance response (LSPR) which could be easily tuned by optimising the size and shape of the nanoparticles 2–4. For the application of solar cell, material required should be of high purity grade without any secondary product contamination. Numerous research activities have been reported to attempt these nanoparticles by chemical route in liquid 5 , gas phase 6 and under high vacuum environment 7. But most of the methods limit to control the reaction rate and the formation of secondary products. Radiation induced radiolysis synthesis overcome this problem and provides simple physico-chemical reaction, control over the reaction rate without any contamination under room temperature and atmospheric pressure 8,9. Proton 10 , electron 11 , gamma 12 , and X-ray beams 13 are the suitable irra-diants to induce the reaction by the action of radiolysis of water, results in the generation of hydrated electrons − e () aq which plays the role of strong reducing agent towards metal ions 14. Several attempts has been imparted to synthesize the metal nanoparticles by these radiation induced techniques, out of which gamma rays provide the low polydispersity product but lags behind due to their constrain over the safety concerns, irradiation time and in-situ characterization. On the other hand X-rays resolve these issues, provides longer irradiation time (as long as required), in-situ characterization 13 and are widely available at laboratory and synchrotron light source. Synchrotron light source provides the X-rays of variable energy with fine control over the wavelength which could be optimized for the desired application. X-ray energy is efficient to trigger the reaction by dosimeteric based radiolysis process, as it commands the reaction rate mechanism and provides the facility to investigate the element specific electronic structural properties 15. Many research groups are indulged to use the synchrotron X-rays for the formation of metallic nanoparticles. Neal N. Cheng 16 reported the chemical enhancement by NPs

Influence of catalytic gold and silver metal nanoparticles on structural, optical, and vibrationa... more Influence of catalytic gold and silver metal nanoparticles on structural, optical, and vibrational properties of silicon nanowires synthesized by metal-assisted chemical etching

Hydroxyapatite (HA) is a form of calcium & phosphate and constitutes large amount of human bone, ... more Hydroxyapatite (HA) is a form of calcium & phosphate and constitutes large amount of human bone, dental enamel and dentin. HA is widely acceptable as purifier for proteins, drug delivery and body implant material. Structure, density & chemical phase should be specific in order to fit for each application. In this paper, Structural characterization of novel HA incorporated with silver nanoparticles (AgNPs) has been investigated for its application in orthopedic body implants. Silver nanoparticles used in this application are of anisotropic in nature which shows enhanced antibacterial properties in comparison to spherical one. XRD reveals that synthesized nanocomposite has 87% crystallinity with hexagonal geometry as similar to the HA. TEM micrographs shows that the average particle size of nanocomposite is 58.38 nm with polydispersity of 30.73 and is well suitable for orthopaedic body implantation.

The manuscript deals with the green synthesis of anisotropic silver nanoparticles (AgNPs). For sy... more The manuscript deals with the green synthesis
of anisotropic silver nanoparticles (AgNPs). For synthesis,
the maltose has been used as reducing and polyvinyl
pyrrolidone (PVP) as capping agent and the reaction has
been initiated using microwave heating. A strong SPR band
at 427 nm and a tail around 590 nm in UV–Vis spectrum
of AgNPs, and TEM imaging confirmed the synthesis of
anisotropic nanoparticles (NPs). Microwave irradiation
time, silver precursor concentration and capping agent
concentration affected the particle size as well as particle
size distribution. Antibacterial behaviour of anisotropic
AgNPs was better than their spherical counterparts.

Orthopedic implants are now com- monly used in many surgical procedures to support or replace a d... more Orthopedic implants are now com-
monly used in many surgical procedures to support
or replace a damaged bone. Hydroxyapatite fulfils
the required structural and biological compatibility
issue even-though contact site provides room to grow
microbes.Hydroxyapatite Ca10(PO4)6(OH)2 is an car-
dinal biomaterial and is predominant inorganic inte-
grant of bones and teeth and is widely used in or-
thopaedic body implants to help patients achieve a
better quality of life. In this paper, synthesis of sil-
ver incorporated hydroxyapatite nanocomposite is re-
ported to recover such problems in orthopaedic body
implants

Silver nanoparticles (AgNPs) have been synthesized using maltose as reducing agent and microwave ... more Silver nanoparticles (AgNPs) have been synthesized using maltose as reducing agent and microwave heating as reaction initiator. The nanoparticles are studied for their optical, structural, thermal, zeta potential and electrical properties. The synthesis protocol used is fast and resulted in the formation of multi-shaped AgNPs as indicated by their optical response and TEM. The crystallite size of nanoparticles and strain of the sample was found to be around 39 nm, and 2.3 × 10−1, respectively, as calculated from XRD data. Zeta potential and electrical response both showed almost threefold increase for multi-shaped as compared to isotropic nanoparticles.