Volume 12, Issue 8, August 2021

Advancing Materials towards Climate Neutrality by 2050

Ashutosh Tiwari

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-3
DOI: 10.5185/amlett.2021.081650

In the new decade, International Association of Advanced Materials (IAAM) is committed with its 2030 agenda on “Advancement of Materials to Sustainable and Green World” working in line with the United Nations’ (UN) Sustainable Development Goals. The IAAM also synchronizes its agenda with the action plans of European Green Deal which is aimed to making the Europe as climate neutral by 2050 for which they have taken a set of policy initiatives. The present scenario of the world climate shows that the climate change and the environmental degradation are a major cause of worry for the whole world and an immediate treatment into the situation is the utmost need of the hour.

Efficiency of Nanomaterials for Electrochemical Diagnostics based Point-of-Care Detection of Non-Invasive Oral Cancer Biomarkers

Neeraj Kumar; V. Sorna Gowri;Raju Khan; Pushpesh Ranjan; Mohd. Abubakar Sadique; Shalu Yadav; Ayushi Singhal; Alka Mishra; S. Murali

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-20
DOI: 10.5185/amlett.2021.081651

Oral tumours are the sixth most incessant infection with high mortality and morbidity rates in human beings and they pose a serious threat worldwide owing to their soaring case-fatality rate and metastatic characteristics of spreading to other parts of the body. Nanomaterials as of late have become indispensable components for biosensor platforms due to their fantastic mechanical, electronic, and optical properties. Specific emphasis is laid in this review on electrochemical biosensors working at the molecular levels, which can be classified into mainly three groups i.e., DNA biosensors, RNA biosensors, and protein biosensors as indicated by the type of the analytes. The carbon-based and non-carbon-based nanomaterials utilizing electrochemical procedures for recognizing oral cancer biomarkers are also reviewed. An extensive review has been made to cover ongoing advancements in the field of nanomaterials based as electrochemical biosensors. This study mostly sums up the significant electrochemical methods, the ongoing advancements of electrochemical technique-based biosensor frameworks for the discovery of oral cancer biomarkers. This effort aims to provide the reader with a concise view of new advances in areas on oral cancer biomarkers for electrochemical signal amplification and the innovative electroanalytical techniques which have been utilized in the miniaturization and integration of the sensors.

Hybrid Membrane based on Polymer-doped Phosposilicate and their Characterization

Uma Thanganathan

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-6
DOI: 10.5185/amlett.2021.081652

A class of proton-conducting non-fluorinated hybrid composite membranes was produced based on poly(vinylpyrrolidone)-doped tetraethoxysilicate (TEOS) and triammoniumphosphate ((NH4)3PO4.3H2O) with and without phosphoricacid. The formation of hybrid composites was verified by various analyses, such as XRD and 1 H NMR, and the thermal degradation was determined by thermogravimetric analysis. The proton conductivity was measured using impedance spectroscopy and values of 3.4 × 10 ‒2 S/cm and 2.3 × 10 ‒2 S/cm were obtained at room temperature for the SiO2/P < sub>2O5/(NH4)3PO4/PVP (90/8/2 mol%/1g) and the SiO2/(NH4)3PO4/PVP (90/10 mol%/1g) hybrid composite membranes, respectively. The results were discussed based on the effects of P < sub>2O5 and (NH4)3PO4 on the hybrid composites.

A DFT Study of Interaction of (CdSe)3 Quantum Dots with Nucleobases

Pragati Malik;Rita Kakkar

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-11
DOI: 10.5185/amlett.2021.081653

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) play important roles in the storage of genetic information and protein biosynthesis. Nucleobases, which are nitrogenous bases, are the functional units of these nucleic acids. It is very important to detect changes in the sequence of DNA/RNA, as any mutations in them may cause harm to the organism. Our aim is to verify the use of (CdSe)3 Quantum Dots (QDs), owing to their distinctive optical and electronic properties, for sensing changes in DNA/RNA. Hence, in this work, we have focused on studying the interaction between (CdSe)3 QDs and the five nucleobases (adenine, guanine, cytosine, thymine and uracil) at various probable sites by means of density functional calculations. Several structural, electronic and optical properties, and charge transfer on interaction between the two, have been discussed. The present band gap and charge transfer calculations indicate that binding of (CdSe)3 to guanine is strongest and is weakest with uracil. The vibrational spectral analysis indicates that the intensities of the peaks due to (CdSe)3 enhance on interacting with the nucleobase, and a blue shift is observed in all the interactions. The presence of both the frontier orbitals (HOMO and LUMO) on the QD indicates that (CdSe)3 acts as a guardian of DNA and prevents it from damage. Hence, our studies direct that CdSe QDs can be successfully employed as sensors for these nucleobases.

Low Resistance and High Electromigration Lifetime of Cu-To-Cu Joints Using (111)-Oriented Nanotwinned Copper

Jing-Ye Juang; Kai Cheng Shie; Yu Jin Li; K. N. Tu; Chih Chen

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-4
DOI: 10.5185/amlett.2021.081654

Cu-to-Cu joints of 30 mm in diameter were fabricated using (111)-oriented nanotwinned copper at 300 °C for 20 min in N2 ambient. The joints possess excellent electrical properties. The average resistance and specific contact resistivity are 4.1 mΩ and 3.98 × 10 -8 Ω·cm 2 , respectively for an as-fabricated Cu joint. With a second step annealing at 400 °C, the resistance can be reduced to 3.27 mΩ due to grain growth across the joint interface. There is 50% resistance reduction compared to SnAg solder joints with the same diameter. The electromigration lifetime for Cu-to-Cu joints is at least 750 times longer than solder joints.

Electrochemical Hydrogen Evolution Reaction Triggered by Co2xMo1-xS2 (x = 0. 0.05 and 0.1) in Acidic Medium

Aruna K Kunhiraman; Bradha Madhavan

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-4
DOI: 10.5185/amlett.2021.081655

Facile solvothermal route was adopted for the synthesis of Co2xMo1-xS2 with x = 0, 0.05 and 0.1. Higher HER activity was exhibited by x = 0.1 in Co doped MoS2, with a current density -140 mAcm -2 at an overpotential of -100 mV. At lower overpotential both the compositions exhibited almost same activity, whereas with the increase in the overpotential and under continuous electrochemical operation, the active sites of composition with x = 0.1 was triggered and it was reflected in its HER activity.

Effect of La Dopant in Modified Bismuth Ferrite Ceramics

R.K. Parida; R. K. Bhuyan;S. K. Parida; B.N Parida

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-9
DOI: 10.5185/amlett.2021.081656

The La modified bismuth ferrite perovskite Bi0.6La0.4FeO3 (BLF) is prepared by cost-effective high solid-solution casting technique. Formation of composite is checked through X-ray diffraction and also notable that there is phase transition from rhombohedral (R3c) to orthorhombic (Pbnm). The average crystalline size (DSC) and mechanical lattice strain are 63.8 nm and 0.147% respectively as calculated by Williamson-Hall method. The frequency bands corresponding to Bi-O, LaO, and FeO stretching vibration confirm that La +3 ions completely incorporate the Bi +3 ions in the A-site of the single perovskite. The SEM micrograph suggests that the sample has distinct grains and well-defined grain boundaries and the average grain size (DSEM) is about 13.9 μm. The rate of agglomeration that acquire in the sample (DSEM/ DSC = 219) confirms the excellent connectivity of grains which stands possible reason for the high dielectric and conductivity. The impedance analysis provided the fact that bulk resistance (Rb) decreases from 6.662 x 10 5 Ω at 25 0 C to 1.000 x 10 -2 Ω at 350 0 C; suggesting NTCR behaviour of the material. The activation energy increases from 201 meV to 677meV with temperature supports a thermally activated conduction mechanism. The thermally activated relaxation process is controlled by the immobile charge carriers at lower temperature range while controlled by defects at higher temperatures which suggests the presence of hopping mechanism. The gap between the peak of and is becoming wide with temperature suggests a non-Debye type character. The semicircular arcs in both Nyquist plots and Cole-Cole plots are confirming the semiconductor nature.  

Biogenic Capped Silver Nanoparticles in Lablal Purpureus Pod Extract Exhibit Selective Antibacterial and Synergistic Anticancer Activity

S. J. Kamble; K. D. Pawar; P. D. Kamble; J. M. Patil; V. J. Sawant

Advanced Materials Letters, 2021, Volume 12, Issue 8, Pages 1-9
DOI: 10.5185/amlett.2021.081657

Biogenic Pod extract stabilized silver nanoparticles were synthesized by wet chemical route in negatively charged precursors. These green synthesized silver(0) nanoparticles with positive charges and neutralized by pod precursors had exhibited oval morphology, 21.5 nm. mean crystallite size and 462 nm. absorption band on the basis of UV-Vis., PXRD spectrometric and TEM analysis. The elemental composition and presence of silver(0) in pod extract flavonoid precursors of nanoparticles was proved on the basis of EDAX characterization. The positive surface capping and charges were estimated on the basis of FTIR and UV-Vis. Spectroscopy. The antibacterial testing of the nanoparticles had proved high surface interaction with gram negative bacteria than gram positive bacteria. The in vitro MTT assay for anticancer activity on MCF-7cells have been elaborated the better biocompatibility at 20 ppm. suspension than standard control drug and pod extract for nanoparticles, which were correlated to better positive charge on surface for interaction with highly negative charged breast cancer cells. Hence these biogenic stable silver nanoparticles had shown better ROS dependant biomedical property for cell particle interaction with synergistic and selective antibacterial and anticancer formulation property for selective biocompatibility.