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Electrochemical CO 2 reduction is crucial in combatting climate change and advancing sustainable energy practices by converting CO 2 into valuable chemicals and fuels, thereby reducing atmospheric CO 2 levels and enabling the storage and utilization of renewable energy from intermittent sources like solar and wind. The selection of electrode materials and platform design plays a critical role in enhancing reaction efficiency and product selectivity during CO 2 reduction. Various metals, both in their solid forms and coated over substrates, have been used in electrochemical CO 2 RR. In this study, we utilized electrodeposition to modify the plastic chip electrode (PCE), depositing lead metal onto it through a galvanostatic method at a current density of 100 mA/cm 2 from a 0.1 M Pb(NO 3 ) 2 aqueous solution. Pb-coated electrodes are crucial due to their high selectivity, efficiency, cost-effectiveness, and flexibility as electrode materials. Their good stability and durability make them ideal for long-term applications. The electrochemical reduction of carbon dioxide using the Pb/PCE electrode as the cathode has been investigated, focusing on assessing how different electrolysis potentials influenced the faradaic efficiency of formic acid production. Our results demonstrated that the peak faradaic efficiency, reaching 86.2%, was achieved at -0.7 V vs RHE over a 5 h electrolysis period.

Transforming CO 2 to CO via reverse water-gas shift (RWGS) reaction is widely regarded as a promising technique for improving the efficiency and economics of CO 2 utilization processes. Moreover, it is also considered as a pathway towards e-fuels. Cu-oxide catalysts are widely explored for low-temperature RWGS reactions; nevertheless, they tend to deactivate significantly under applied reaction conditions due to the agglomeration of copper particles at elevated temperatures. Herein, we have synthesized homogeneously distributed Cu metallic nanoparticles supported on Mo 2 C for the RWGS reaction by a unique approach of in situ carburization of metal-organic frameworks (MOFs) using a Cu-based MOF i.e. HKUST-1 encapsulating molybdenum-based polyoxometalates. The newly derived Na-Cu-Mo 2 C nanocomposite catalyst system exhibits excellent catalytic performance with a CO production rate of 3230.0 mmol g cat -1 h -1 with 100% CO selectivity. Even after 250 h of a stability test, the catalyst remained active with more than 80% of its initial activity.

Herein, we report the synthesis of two-dimensional chiral Zn II Salen covalent organic frameworks (COFs) ( 2 ) via rapid microwave-promoted condensation of C 3 -symmetric 1,3,5-tris[(5- tert -butyl-3-formyl-4-hydroxyphenyl)ethynyl]benzene 1 with (1 R ,2 R )-1,2-diaminocyclohexane in excellent yields. The synthesized chiral Zn II Salen COF ( 2 ) showed a 454 m 2 g -1 BET surface area with excellent crystallinity and thermal stability. Further, the post-synthetic metal exchange reaction was performed for chiral Zn II Salen COFs ( 2 ) with Mn(OAc) 2 ·4H 2 O to synthesize chiral Mn III Salen COFs ( 3 ) and utilized as an effective heterogeneous catalyst for the enantioselective epoxidation of styrenes and chromenes to afford chiral epoxides up to 72% ee . Chiral Mn III Salen COF ( 3 ) could easily be separated by centrifugation and reused up to four recycles with an observable loss in activity without impairing enantioselectivity.

Sustainable chemistry research prioritizes reducing atmospheric carbon dioxide, and one logical solution is to develop adsorbents suitable for carbon capture and utilization. In this work, a new family of three-dimensional (3D) flower-like Mn-promoted MgO was synthesized by the coprecipitation method and used as an adsorbent for CO 2 capture and a catalyst for CO 2 utilization. The scanning electron microscopy (SEM) analysis of the samples shows a 3D architecture composed of thin nanosheets. The X-ray diffraction (XRD) analysis confirms the presence of the MgO with a cubic structure, while X-ray photoelectron spectroscopy (XPS) reveals the existence of Mn particles as a combination of Mn 3+ and Mn 4+ ions on MgO. N 2 adsorption-desorption experiments highlight the beneficial contribution of Mn particles to surface area enhancement and reveal the existence of mesopores. Furthermore, the designed 3D Mn-doped MgO as an adsorbent demonstrates its capability to improve the ability of MgO to adsorb CO 2 (from 0.28 mmol/g for pure MgO to 0.74 mmol/g) in ambient conditions and it is regenerable up to 9 cycles with a slight variation after the third cycle. Moreover, Mn-doped MgO shows good catalyst activity for the oxidation of ethylbenzene derivatives to carbonyl compounds in the presence of CO 2 and O 2 . Mn-15/MgO shows excellent catalytic behavior with a conversion of 97.4 and 100% selectivity. Also, it is regenerable with an insignificant decrease in conversion (∼11.63%) after seven cycles, while the selectivity of acetophenone remains stable. The analyses of the recycled sample suggest that the chemical compositions of Mn and Mg influence the catalytic activity of those Mn-promoted MgO materials. The role of CO 2 gas in the aerobic oxidation of ethylbenzene to acetophenone has also been proved. Finally, the control experiments and EPR studies reveal that the reaction takes place through the formation of radicals.

In this work, we have reported a noble metal free heterogeneous photocatalyst to carry out direct (het)arene C-H arylation and solvent-free CO 2 capture via single-electron transfer processes at room temperature and under pressure. The catalytic system comprises a cobalt(III) complex grafted over the silica coated magnetic support for the efficient recovery of the photocatalytic moiety without hampering its light-harvesting capability. The novel Earth-abundant cobalt(III) based photocatalyst possesses various fascinating properties such as high surface area to volume ratios, large pore volume, crystalline behaviour, high metal loading, excellent stability and reusability. The general efficacy of the highly abundant and low-cost cobalt based heterogeneous nanocatalyst was checked for the selective conversion of aryldiazonium salts into synthetically and pharmaceutically significant biaryl motifs under ambient conditions upon irradiation with visible light. The highly efficient photocatalytic conversion of carbon dioxide (CO 2 ) to a value-added chemical was accomplished under mild reaction conditions with high selectivity, showing the added benefit of operational simplicity.