In this research, the effects of Van der Waals forces on the structural, elastic, electronic, and optical properties of bulk transition metals dichalcogenides (TMDs) were studied using a novel exchange-correlation functional, vdW-DF3. This new functional tries to correct the hidden Van der Waals problems which are not reported by the previous exchange functionals. Molybdenum dichalcogenide, MoX 2 (X = S, Se, Te) was chosen as a representative transition metal dichalcogenide to compare the performance of the newly designed functional with the other two popular exchange-correlation functional; PBE and rVV10. From the results so far obtained, the analysis of the structural properties generally revealed better performance by vdW-DF3 via the provision of information on lattice parameters very closer to the experimental value. For example, the lattice constant obtained by vdW-DF3 was 3.161 Å which is very close to 3.163 Å and 3.160 Å experimental and theoretical values respectively. Calculations of the electronic properties revealed good performance by vdW-DF3 functional. Furthermore, new electronic features were revealed for MoX2 (X = S, Se, Te). In terms of optical properties, PBE functional demonstrates lower absorption than vdW-DF3, as such it can be reported that vdW-DF3 improves photon absorption by TMDs. However, our results also revealed that vdW-DF3 performed well for MoS2 than for MoSe2 and MoTe2 because of the lower density observed for the S atom in MoS2.

World is experiencing rapid commercial growth and urbanization. Carbon (IV) oxide (CO2) emissions into the atmosphere is increasing. As a result, a more effective energy policy is required.   As a matter of fact, sustainable environmental quality has been identified as a critical component of long-term economic development success. Many studies have found that lower CO2 emissions are an indicator of improved environmental quality. In the future, low-cost photoelectric technologies with superior sun-to-energy power conversion efficiency, extended lifetime, and low toxicity may replace conventional silicon-based solar panels and provide effective global illumination. Dye-sensitized solar cells (DSSCs) based on the zinc oxide nanorods are capable of all the aforementioned features. Zinc-oxide (ZnO) nanostructures are important for dye synthesis solar cells, and it is a leading semiconductor that researchers are interested in. The primary objective/purpose of this resarch is to highlight impact of carbon (IV) oxide and the potential of DSSC for reducing CO2 discharges into the atmosphere. Method of ZnO NRs deposition on seed layer coated FTO Glass by Hydrothermal method was also expounded. The morphology of nanorods is presented, based on the available literature it concludes that the production of efficient DSSCs can reduce reliance on fossil fuels, which are the agent of ozone depletion layer due to green gas emissions.