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Depletion of oil and gas resources is a major concern for researchers and the global community. Researchers are trying to develop a way to overcome these issues using the Fischer-Tropsch synthesis (FTS) process. The FTS reaction converts a mixture of hydrogen and carbon monoxide gases into a liquid fuel. The reactions are performed in the reactor and in the presence of a catalyst. A series of catalysts, such as iron, cobalt, nickel, and ruthenium, have been used for the FTS process. In iron-based catalysts, the Fe5C phase is the active phase that produces C5+ hydrocarbons. At higher conversion rates, the presence of water in the products is a problem for cobalt catalysts because it can trigger catalyst deactivation mechanisms. Ni-based catalysts play key roles as base catalysts, promoters, and photothermal catalysts in FTS reactions to produce different useful hydrocarbons. Ruthenium catalysts offer not only high activity but also selectivity toward long-chain hydrocarbons. Moreover, depending on the Ru particle size and interaction with the oxide support, the catalyst properties can be tuned to enhance the catalytic activity during FTS. The detailed reaction pathways based on catalyst properties are explained in this article. This review article describes the issues and challenges associated with catalysts used for the FTS process. [ABSTRACT FROM AUTHOR]

Heterogeneous growth of photocatalysts on different porous substrates is a solution to avoid secondary pollution caused by composite photocatalysts themselves. However, the heterogeneous growth of composite photocatalysts with nitrogen-doped carbon quantum dots (NCQDs) inclusions-introduced during synthesis-impedes the direct growth on the substrate. To overcome this problem, NCQDs were grown on a Co 9 S 8 (NCQDs-G@Co 9 S 8 ) layer, decorated on cotton fabric. This optimal coupling mode of NCQDs and Co 9 S 8 showed 54% degradation, compared to 33% dye degradation via NCQDs-doped Co 9 S 8 (NCQDs-D@Co 9 S 8 ). The change in the crystal structure and its lower loading on fabric results in significantly lower performance of NCQDs-D@Co 9 S 8 . Even with the combination of both surface growth and doping (NCQDs-DG@Co 9 S 8 ), the performance was still limited to 42%. In addition, the optimum growth concentration of NCQDs on Co 9 S 8 was observed for 7.5 w/w %, resulting in 92% photocatalytic activity (PCA) in 80 min. Comparing different surface states formed in NCQDs using different solvents, water-based surface states (oxygen-rich surface) are most suitable for the dye degradation. NCQDs-G@Co 9 S 8 also offers 67% Cr-VI reduction to Cr-III, showing its suitability for both inorganic and organic compounds. Better electrode performance was related to suitable charge separation of the composite, where -OH groups mainly contribute in the photocatalytic dye degradation.., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)