Solar cells based on p-conjugated donor-acceptor (D-A) organic molecular systems are a promising alternative to conventional electrical energy generation. D-A molecular systems, which have a triphenylamine (TPA) moiety linked with a benzothiadiazole (BTD) moiety, open the potential development of new small molecule donors for bulk heterojunction (BHJ) solar cells. Here, a series of donor-acceptor-π-acceptor (D-A-π-A) small molecule donors (SMD) derived from triphenylamine (TPA) donor and benzothiadiazole (BTD) acceptor building blocks, were designed for BHJ organic solar cells. The small molecule donors SMD1-4 were studied using density functional theory (DFT) and time dependent-DFT (TDDFT) methods, to understand the effect of cyano and fluorine group functionalization on their properties. The effect of structure alteration by cyano and fluorine group functionalization on the optoelectronic properties, the calculated highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) and the HOMO-LUMO gaps were theoretically explored. The Voc (open-circuit photovoltage) and fill factor (FF) for SMD1-4 were obtained with a PC71BM acceptor, which showed that these organic small molecules are potential small molecule donors for organic bulk heterojunction solar cells.
As frontier materials, graphene oxide (GO) and graphene have penetrated almost all research areas and advanced numerous technologies in sensing, electronics, energy storage, catalysis, water treatment, advanced composites, biomedical, and more. However, the affordable large-scale synthesis of high-quality GO and graphene remains a significant challenge that negatively affects its commercialisation. In this article, firstly, a simple, scalable approach was demonstrated to synthesise high-quality, high yield GO by modifying the improved Hummers method. The advantages of the optimised process are reduced oxidation time, straightforward washing steps without using coagulation step, reduction in cost as eliminating the use of phosphoric acid, use of minimum chemical reagents, and increased production of GO per batch (~ 62 g). Subsequently, the produced GO was reduced to reduced graphene oxide (rGO) using three different approaches: green reduction using ascorbic acid, hydrothermal and thermal reduction techniques. The GO and rGO samples were characterised using various microscopy and spectroscopy techniques such as XRD, Raman, SEM, TEM, XPS and TGA. The rGO prepared using different methods were compared thoroughly, and it was noticed that rGO produced by ascorbic acid reduction has high quality and high yield. Furthermore, surface (surface wettability, zeta potential and surface area) and electrical properties of GO and different rGO were evaluated. The presented synthesis processes might be potentially scaled up for large-scale production of GO and rGO.
Corrosion is a natural, inevitable process, and is one of the world's most serious problems. Losses incurred due to corrosion are extremely expensive for society. Several technological strategies have been explored and implemented to address these losses. The use of inhibitors to prevent corrosion is a common and efficient method to reduce corrosion losses. This review covers Al and Al-composite corrosion inhibitors in chloride-containing solutions, because of their popularity in a broad array of industrial applications. A vast number of studies in the literature detail the common tendency of Al and Al-composites with reinforcements to deteriorate. Accordingly, it is worthwhile to employ inhibitors to protect them, as discussed in the present work. The emphasis is on selecting the smartest corrosion inhibitor and evaluating its performance. According to the study, the most commonly used corrosion inhibitors are 1,4-naphthoquinone (NQ), 1,5-naphthalene diol, 3-amino-1,2,4-triazole-5-thiol (ATAT), ammonium tetrathiotungstate, clotrimazole, amoxicillin, antimicrobial and antifungal drugs. Electrochemical impedance spectroscopy (EIS), potentiodynamic (PDP), and weight loss were among the most commonly used modern electrochemical technologies to test inhibitors’ efficacy under environmental conditions.
Purpose – The study aims to examine the students’ perspective (stream wise) of parameters affecting the undergraduate engineering education system present in a private technical institution in NCR, Haryana, India. Research design, data, and methodology – It is a descriptive type of research in nature. Questionnaire Based Survey has been used to collect the data. The sample size for the study is 500 comprising of the students respondents. The sample has been taken randomly and the questionnaire was filled by the students (pursuing B. Tech) chosen on the random basis from a private technical educational institution in NCR, Haryana, India. For data analysis and conclusion of the results of the survey, statistical tool like F test was performed with the help of high quality software; SPSS. Conclusion – Analysis of variance revealed statistically no difference between the mean number of the groups (stream wise) for the parameters "Selection", "Academic Excellence", "Infrastructure", "Personality Development and Industry Exposure" and "Management and Administration". While Analysis of variance revealed statistically difference between the mean numbers of the groups for the parameter "Placements".