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Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used for an in situ thermal decomposition study of Zn(CH 3 COO) 2 ·2H 2 O forming ZnO nanoparticles. TOF-SIMS spectra were recorded at regular temperature intervals of 25• C in positive and negative detection modes in a dynamic thermal process.Controlled heating (5 • C min −1 ) of Zn(CH 3 COO) 2 ·2H 2 O was also carried out using thermogravimetric analysis (TGA) in an oxygen atmosphere (20 ml min −1 ). Nearly spherical ZnO nanoparticles with no agglomeration and a narrow size distribution (diameter ∼50 nm) were observed, which were characterized using scanning electron microscopy, transmission electron microscopy and x-ray diffraction. In situ thermo-TOF-SIMS was used to monitor the 64 Zn + and 66 Zn + ion abundances as a function of temperature, which showed a similar profile to that observed for weight loss in TGA during decomposition. Based on the experimental results, a possible decomposition mechanism for the formation of ZnO is proposed.

Considering the potential applications of transition metal doped nanostructured materials and the advantages of novel, cost-effective and environmental friendly biosynthesis methods, Ni-doped SnO2 nanomaterials have been synthesized using remnant water (ideally kitchen waste) collected from soaked Bengal gram beans (Cicer arietinum L.) extract. The structural and optical properties of the Ni-doped SnO2 nanostructures were studied using various techniques such as UV/visible spectroscopy, FT-IR spectroscopy, X-ray powder diffraction (XRD), Field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The SEM, TEM images and XRD of biosynthesized Ni-SnO2 nanoparticles reveal uniform size distribution with the average size of 6 nm and confirmed the formation of rutile structure with space group (P42/mnm) and nanocrystalline nature of the products with spherical morphology.Subsequently, Ni-doped biosynthesized SnO2 nanoparticles were coated onto the glass substrate using doctor blade method to form thin films. The NO2 sensing properties of the materials have been studied in comparison with other gases.The reported gas sensing results are promising, which suggest that the Ni-dopant is a promising noble metal additives to fabricate low cost SnO2 based sensor.

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Nanostructured hydroxyapatite (HAp) is the most favorable candidate biomaterial for bone tissue engineering because of its bioactive and osteoconductive properties. Herein, we report for the first time ultrasound-assisted facile and economic approach for the synthesis of nanocrystalline hydroxyapatite (Ca (PO ) (OH) ) using recycled eggshell biowaste referred as EHAp. The process involves the reaction of eggshell biowaste as a source of calcium and ammonium dihydrogen orthophosphate as a phosphate source. Ultrasound-mediated chemical synthesis of hydroxyapatite (HAp) is also carried out using similar approach wherein commercially available calcium hydroxide and ammonium dihydrogen orthophosphate were used as calcium and phosphate precursors, respectively and referred as CHAp for better comparison. The prepared materials were characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy to determine crystal structure, particle morphology, and the presence of chemical functional groups. The nanocrystalline EHAp and CHAp were observed to have spherical morphology with uniform size distribution. Furthermore, mechanical properties such as Vickers hardness, fracture toughness, and compression tests have been studied of the EHAp and CHAp samples showing promising results. Mechanical properties show the influence of calcination at 600°C EHAp and CHAp material. After calcination, in the case of EHAp material an average hardness, mechanical strength, elastic modulus, and fracture toughness were found 552 MPa, 46.6 MPa, 2824 MPa, and 3.85 MPa m , respectively, while in the case of CHAp 618 MPa, 47.5 MPa, 2071 MPa, and 3.13 MPa m . In vitro cell studies revealed that the EHAp and CHAp nanoparticles significantly increased the attachment and proliferation of the hFOB cells. Here, we showed that EHAp and CHAp provide promising biocompatible materials that do not affect the cell viability and proliferation with enhancing the osteogenic activity of osteoblasts. Moreover, hFOB cells are found to express Osteocalcin, Osteopontin, Collagen I, Osteonectin, BMP-2 on the EHAp and CHAp bone graft. This study demonstrates the formation of pure nanocrystalline HAp with promising properties justifying the fact that the eggshell biowaste could be successfully used for the synthesis of HAp with good mechanical and osteogenic properties. These findings may have significant implications for designing of biomaterial for use in orthopedic tissue regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2935-2947, 2017.

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Single step and completely green room temperature biosynthesis of microscale size triangular gold prisms (approximately 25 nm thick) using remnant water collected from soaked Bengal gram beans (Cicer arietinum L.) is reported for the first time. Extracellular transport of protein and biomolecules from protein rich gram beans mediate the reduction of aqueous Au3+ ions and direct the growth of triangular prisms. The growth of triangular gold prisms is monitored by UV-vis spectrometer and supported by complementary characterizations using UV-vis/NIR, TEM, EDS, light microscope, XRD, XPS, ATR-FTIR, and ESI-MS. Plausible mechanism for the formation of microscale size triangular gold prisms is discussed. Effect of varying compositions of gram bean extract and aqueous Au3+ solution governing the morphology of the resultant gold particles is also investigated. Procuring the reducing, growth directing, and stabilizing molecules from the remnant water (extract), which normally would have been a kitchen waste, and water as a universal solvent makes it a completely green process displaying both environmental and economic advantages. Furthermore, this biosynthesis approach is simple, green, and an eco-friendly alternative to chemical synthesis of triangular gold prisms with rates comparable to chemical methods.