• HUI JIANG

Articles written in Bulletin of Materials Science

• Characterization of amorphous hydrogenated carbon films deposited by MFPUMST at different ratios of mixed gases

Amorphous hydrogenated carbon films (𝑎-C:H) on 𝑝-type (100) silicon wafers were prepared with a middle frequency pulsed unbalanced magnetron sputtering technique (MFPUMST) at different ratios of methane–argon gases. The band characteristics, mechanical properties as well as refractive index were measured by Raman spectra, X-ray photoelectron spectroscopy (XPS), nano-indentation tests and spectroscopic ellipsometry. It is found that the 𝑠𝑝3 fraction increases with increasing Ar concentration in the range of 17–50%, and then decreases when Ar concentration exceeds 50%. The nano-indentation tests reveal that nano-hardness and elastic modulus of the films increase with increasing Ar concentration in the range of 17–50%, while decreases with increasing Ar concentration from 50% to 86%. The variations in the nano-hardness and the elastic modulus could be interpreted due to different 𝑠𝑝3 fractions in the prepared 𝑎-C:H films. The variation of refractive index with wavelength have the same tendency for the 𝑎-C:H films prepared at different Ar concentrations, they decrease with increasing wavelength from 600 to 1700 nm. For certain wavelengths within 600–1700 nm, refractive index has the highest value at the Ar concentration of 50%, and it is smaller at the Ar concentration of 86% than at 17%. The results given above indicate that ratio of mixed gases has a strong influence on bonding configuration and properties of 𝑎-C:H films during deposition. The related mechanism is discussed in this paper.

• Sensing of polymeric sensor-based rhodamine B derivative for metal cations in complete aqueous solution

The water-soluble polymeric chemosensor poly(AM-GRBD) has been synthesized by precipitation copolymerization with the functional monomer, GRBD, which was made of N$"$-(rhodamine B-yl) diethylenetriamineand glycidyl methacrylate (GMA) and a hydrophilic co-monomer acrylamide (AM). The chemical sensor behaved as a fluorescent and chromogenic sensor towards various heavy metal cations and transition metal cations; particularly,Cr$^{3+}$, Fe$^{3+}$ and Hg$^{2+}$ ions in completely aqueous media. The fluorescence of poly(AM-GRBD) was enhanced by Cr$^{3+}, Fe$^{3+}$and Hg$^{2+}$metal ions. Moreover, during titration of Cr$^{3+}$, Hg$^{2+}$or Fe$^{3+}\$ to the aqueous solution of poly(AM-GRBD), the visual colour changed from colourless to pink or brown yellow under visible light.

• # Bulletin of Materials Science

Volume 43, 2020
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020