Pachaiyappa's College is one of the oldest educational institutions in Chennai, in the South Indian state of Tamil Nadu. In addition, it is the first sole Indian college in Madras Presidency.
The development of high-performance and sustainable photocatalysts is pivotal for mitigating environmental pollution, particularly in the treatment of dye-contaminated industrial wastewater. In this study, we report the synthesis of a graphitic carbon nitride/cadmium sulfide (g-CN/CdS) composite via a facile hydrothermal method, aimed at enhancing visible-light-driven photocatalytic efficiency and long-term stability. Comprehensive structural and chemical characterizations, including X-ray diffraction (XRD) and Fourier-transform infrared (FT-IR) spectroscopy, confirm the successful anchoring of CdS nanoparticles onto the g-CN matrix. Photocatalytic performance evaluations reveal that the g-CN/CdS composite exhibits a significantly higher degradation rate of Congo Red (CR) dye compared to its individual counterparts, achieving an exceptional degradation efficiency of 99.85 % under visible-light irradiation. The superior activity is primarily attributed to the synergistic coupling between g-CN and CdS, which facilitates efficient charge carrier separation, suppresses electron-hole recombination, and mitigates photocorrosion. This work underscores the importance of heterojunction engineering in optimizing photocatalytic materials and offers a viable pathway for designing next-generation nanocomposites for eco-friendly and scalable wastewater remediation technologies.
This investigation explores the influence of substrate temperature on the inherent characteristics of Cu2CoSnS4 (CCTS) thin films, which consist of earth-abundant and non-toxic elements. In addition, it examines the optoelectronic application of the prepared thin films. We varied the substrate temperature from 275 degrees C to 375 degrees C in increments of 25 degrees C. We studied the crystalline structure and phases present in the CCTS thin films using X-ray diffraction and Raman spectroscopy techniques. We also used scanning electron microscopy, energy dispersive spectroscopy and UV-Vis-NIR spectrophotometry to analyze surface morphology, elemental composition, and optical properties, respectively. X-ray diffraction and Raman analysis confirm the formation of CCTS at all substrate temperatures, with the highest intensity occurring at 350 degrees C and no secondary phases present. The sample prepared at 350 degrees C exhibited the highest absorption and the lowest optical band gap (1.69 eV). This sample also achieved the highest photocurrent (42 mu A), along with a responsivity of 0.812 A/W, a detectivity of 5.43 x 1010 Jones, and an EQE of 189 %. These results demonstrate a promising approach for fabricating highperformance photodetectors with tunable properties across a broad spectrum.
A highly sensitive electrochemical sensor was developed using a graphene-supported copper sulfide/zirconium oxide nanocomposite (Graphene@CuS/ZrO)-modified glassy carbon electrode (GCE) for the simultaneous and individual detection of theophylline (TPN) and cytosine (CTN). The nanocomposite was synthesized at room temperature via a simple stirring and ultrasonication process, where graphene provided excellent electrical conductivity and CuS/ZrO nanoparticles offered abundant electrocatalytic sites. The electrochemical responses of TPN and CTN were thoroughly examined using cyclic voltammetry (CV), square wave voltammetry (SWV), differential pulse voltammetry (DPV), chronoamperometry, and amperometry. The Graphene@CuS/ZrO exhibited noteworthy electrocatalytic activity toward both analytes, with well-resolved oxidation peaks that allowed simultaneous detection without mutual interference. Under optimized conditions, the sensor displayed a linear response for TPN from 0.5 to 570 & micro;M and for CTN from 0.3 to 610 & micro;M, with corresponding detection limits of 0.045 and 0.028 & micro;M, respectively. The fabricated electrode demonstrated good reproducibility, stability, sensitivity, and selectivity in the presence of common interfering species. Moreover, the biosensor was successfully applied to determine TPN and CTN in pharmaceutical formulations and biological samples, highlighting its potential for practical electroanalytical applications.
A comprehensive experimental and theoretical investigation of sarcosinium tartrate (C3H8NO2+·C4H5O6−), a proton-transfer molecular salt is presented in this study. Single crystals of sarcosinium tartrate (SRT) were successfully grown by the slow evaporation technique yielding optically transparent crystals with dimensions of approximately 23 × 11 × 6 mm3 and structure was characterized by single-crystal X-ray diffraction, confirming a triclinic crystal system with a non-centrosymmetric arrangement P1 space group. Vibrational analysis performed through FTIR spectroscopy, supported by DFT calculations at the B3LYP/6–311 + + G (d, p) level, showed excellent agreement, validating the molecular structure and functional group assignments. UV–vis–NIR spectrum revealed high optical transparency ( 96
Tamil literature has long served as a powerful medium for expressing social realities and advocating progressive change. Among modern Tamil writers, M. Karunanidhi stands out as a significant literary and political figure whose works reflect the ideological foundations of the Dravidian movement. His short stories address social inequality, rationalism, and the dignity of marginalized communities, particularly women. Many of his stories have been translated into English by P. Raja and edited by P. Marudanayagam and V. Murugan from Bharathiar University under the title Is in the Original (Short Stories). This paper explores the representation of women’s self-respect and social reform in three selected stories: The Dancer (நடனக் கலைஞர்), The Last Phase (கடைசி கட்டம்), and The Great Escape (கிரேட் எஸ்கேப்). Karunanidhi portrays women not as passive victims but as individuals asserting their dignity and challenging unjust norms. His works emphasize rational thinking, education, and equality as essential for social transformation. The study uses qualitative textual analysis to examine how female characters embody self-respect, agency, and resistance to patriarchy. The analysis reveals that Karunanidhi’s writings promote progressive ideals resonant with the Self-Respect Movement initiated by Periyar E. V. Ramasamy. His stories question gender discrimination, social hypocrisy, and moral double standards while advocating women’s empowerment and justice. The paper concludes that Karunanidhi’s short stories shape feminist consciousness within modern Tamil literature and remain relevant in contemporary gender equality and social reform discussions.
