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Even though copper–tungsten has shown signs of potentials, relatively little is currently known about its appropriateness for photovoltaic application. This paper aims to evaluate the suitability of copper-tungs oxides as photovoltaic absorbers while investigating the consequences of oxygen content variation.

Using profilometry, Hall measurements, Seebeck test and spectrophotometry, grown samples were defined. Samples of 5 standard cubic centimeters per minute (sccm) and 7 sccm exhibited appropriate characteristics and were further tested using personal computer one dimension (PC1D) computational simulation at the system stage. To grow materials with an average thickness below 0.45 µm, magnetron co-sputtering was used. Three sample sets, varied by oxygen flow rate, were made with flow rates of 5sccm, 7sccm and 9sccm, respectively.

Some samples proved to be effective absorbers, using a cadmium telluride device as the criterion of output calculation, with one sample chosen as ideal for each type of flow rate. For the chosen samples, an optimum thickness was also obtained, i. It was discovered that thinner cells, optimal for both groups with 0.6 µm, performed better to than other thicknesses.

The material also demonstrated prospects for applications in window layers, but more needs to be known.

Thin film material properties and their operating processes are relatively complex, so it is important to find simple and cost-effective ways to forecast performance. While relatively new, numerical modeling has proven to be very useful in defining the critical properties of thin film devices, thereby helpful for predictions of performance. Solar cell capacitance simulator one dimension, amorphous semiconductor analysis, personal computer one dimension (PC1D), analysis of micro-electronic and photonic structures and automat for simulation for heterostructures (33) are several common models in the thin film industry. Due to its availability and relative ease of use, PC1D was used in this project.

As the search for the balance among performance, cost, reliability and availability continue, more absorber components continue to evolve, notably from the chalcogenides. Because of their ability to absorb light, ternary transition metal chalcogenides are useful in the production of hydrogen and in the energy storage sector, as well as in the production of light-emitting diodes and solar photovoltaic (PV).

There are several methods for the manufacture of copper–tungsten alloys, but the process of combinatorial sputtering of magnetrons provides satisfactory results even for the manufacture of various other materials. Cu₂WSe₄, an excellent alternative to sputtering, is one of the very few copper–tungsten selenide materials tested, synthesized by hot simple injection to have strong crystallinity and lacks impurity. The optical properties of colloidal Cu₂WSe₄ show that Schottky diode–like behaviors are present in the material, suggesting its potential for use in solar cells. Cu-W alloys could have a lot more to give the PV industry, by all indications. Further exploration of the oxides by this work is thus justified. Transparent conducting oxides, interfacial layers or charge-transporting compounds are commonly used as transition metal oxides. Nevertheless, as absorbers, metal oxides such as BiFeO₃ and the traditionally highly studied Cu₂O have been tested, with Cu₂O showing a conversion efficiency of up to 10% under particular conditions. This displays strong electronic and optical properties, so there might be some possibility of studying other PV absorption metal oxides. The optical properties of colloidal Cu₂WSe₄ show that Schottky diode–like behaviors are present in the material, suggesting its potential for use in solar cells.

This paper aims to investigate the current status of research output published in open access (OA) journals from Brazil, Russia, India, China and South Africa (BRICS) countries from 2010 to 2019 and compare their performances in terms of OA research output.

Papers contributed by the researchers of BRICS countries were searched using an advanced search option in the Web of Science core collection database. The retrieved results were restricted to the “journal articles” published in the “English language” during the time period of 2010 to 2019. After that, the selected papers were again refined by using the “open access” section to identify the research output of BRICS countries published in OA journals.

Total 2,219,943 papers were published from BRICS countries, out of which 402,199 articles were published in OA journals and South Africa has published the highest number of research output in OA journals (31%). Although, there has been a constant increasing growth of research output published in OA journals in BRICS countries from 13,300 papers in 2010 to 82,310 articles in 2019. Engineering and Technology have published the maximum number of papers in OA journals. Researchers of BRICS countries mostly contributed their OA research output in journals published from the USA and Scientific Reports (UK) is identified as one of the leading OA journals. Additionally, among all the BRICS countries, China is found as the promising leader in terms of OA journals publications, the maximum share i.e. 71.25 per cent of total 402,199 OA journal publications have been produced by the highest number 137 (23.41%) of institutions of China and Chinese Academy of Sciences (China) is leading institution with 39,036 papers published in OA journals.

This study is limited to BRICS countries, but it offers theoretical implications for extending its scope to different countries. This study may be used for raising awareness of OA among researchers of BRICS countries and encouraging them to contribute their research work in OA journals. The findings of this study are useful and meaningful in understanding the comparative status of research across countries, disciplines, journals and institutions.

This is the first study in BRICS countries focusing on the research output published in OA journals.