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The present scenario indefinitely needs certain developments in the field of renewable energy as an effective replacement of conventional energy sources. Reflection loss in solar cell is one of the reasons for reduction in power conversion efficiency which can be controlled through antireflective coatings on solar cell surface. This current research focuses on the development of MoSe2 nano-crystalline structure as an effective antireflective material for attaining enhanced light trapping ability. Electrospraying technique was taken into account for the deposition of thin films over the solar cell surface. Transition metal chalcogenide MoSe2 was deposited under argon atmosphere with the coating time of 30–120 min. The impact of thin film MoSe2 coating on solar cell surface was determined through optical, electrical, morphological and thermal studies. The thickness of optimal MoSe2 coating was found to be 761 nm through Atomic Force Microscopy technique. The maximum optical transmittance of 87.6 % was achieved at 90 min of coating (D3) within the spectrum of 300 to 800 nm wavelength. The minimum electrical resistivity of 90 min coated MoSe2 thin film coating over multicrystalline silicon solar cell was measured as 3.93 × 10− 3 Ω-cm. The enhanced power conversion efficiency of MoSe2 coated solar cell under open and closed conditions were found to be 17.13 and 18.67 % especially for D3 solar cell sample, which facilitates maximum transmission of incident photons into the solar cell. From the observed results, it is evident that MoSe2 nanostructure was found to be promising antireflection coating material for multicrystalline silicon solar cell.

Transparent zinc sulfide (ZnS)-aluminium sulfide (Al2S3) composite thin-films are deposited on silicon solar cells through radio frequency (RF) sputtering method at room temperature to investigate the structural, optical, electrical, and thermal characteristics. X-ray diffraction analysis reveals the presence of the powder sample (ZnS-Al2S3) and its average crystallite size is 15.83 nm. The minimum electrical resistivity (ρ), maximum hall mobility (μ), and carrier concentration (N) of ZnS-Al2S3 nano-layer coated solar cells are measured to be 2.98 × 10−3 Ω cm, 14.89 cm2 V−1 s−1 and 24.88 × 1020 cm−3 respectively. For a time period of 25 min, ZnS-Al2S3 nano-layer sputter coating produces the maximum power conversion efficiencies (PCE) of 19.38% and 21%, obtained at open and controlled atmospheric conditions, respectively. The influence of operating temperature at both these open and controlled atmospheric conditions for ZnS-Al2S3 nano-layer coated silicon solar cells is observed. The ZnS-Al2S3 composite demonstrates the properties of a desirable anti-reflection coating material for enhancing the PCE of solar cells.

Natural fibre-reinforced polymer composites are increasingly replacing commercial composite materials. The limitations of conventional composites materials are overcome by green composites, which are easily available, more eco-friendly and less toxic. In the current scenario, green composites are emerging in the field of material science that involves improving their physical, mechanical and thermal properties. The poor interfacial adhesion and surface incompatibility between natural fibre and biodegradable polymers lead to reduced physico-mechanical properties. In order to overcome this issue, physical and chemical modification methodologies of the natural fibre and polymer matrix are employed, among which the addition of coupling agents has a critical contribution. This paper compiles several recent research works in the utilization of coupling agents such as silane, maleic anhydride, isocyanate, triazine, etc., with the various combinations of natural fibres and polymers. In addition to this, the extents of influence of coupling agents on the characteristics of the natural fibre reinforced composite materials are also reported. This gives an overview for the future researchers to identify the gap in the field of green composite materials and novel coupling agents for different natural fibre/polymer matrix combination.

The current research focuses on sol-gel derived synthesis and RF sputter deposition of molybdenum disulphide (MoS2) over polycrystalline Si solar cell. Various coating layers were obtained under different sputter deposition at regular intervals. The influence of MoS2 sputter coating on optical, thermal chemical structural properties was examined through various characterisation techniques. 30 minutes coated solar cell reported maximum light transmittance of 95 % in the visible spectrum and minimum electrical resistivity of 2 × 10-3ohm-cm. 30 minutes coated solar cell exhibited maximum power conversion efficiency (PCE) of 19.19 % (open source) and 21.01 % (controlled source). Thermal imaging data reveal that the optimal coating layer experiences a minimum temperature of 33.9 °C and 49.9 °C. From experimental results, sputter deposited MoS2 Si solar cells experience minimum light reflectance and enhanced cell performance.

Due to environment and sustainability issues, this century has witnessed a global attention in green technology in the field of materials science through the development of composites. So, natural fiber reinforced composites have become important field of green composite. The main objective of this paper is to investigate the effect of sisal fiber reinforcement in epoxy composites with random orientation. Sisal fiber is abundant, low cost, degradable and good strength fiber. Sisal fiber is separated from sisal leaf using suitable techniques and those fibers surface are modified by chemical pre-treatment method (alkali treatment5%NaOH solution). Pre-treated fiber with constant length and volume is reinforced in epoxy matrix. Pure epoxy and sisal fiber reinforced epoxy composites are prepared by hand lay-up method. The prepared composites are tested as per ASTM standard. Tensile strength, compression strength and water absorption test are examined for the composite. The properties of the prepared composites are compared with pure epoxy. Experimental results show that the fiber reinforced composites showed enhanced mechanical properties compared with plain epoxy composites.