Conversion Of Atmospheric CO2 Research Articles

Synergistic Interplay of Dual‐Active‐Sites on Metallic Ni‐MOFs Loaded with Pt for Thermal‐Photocatalytic Conversion of Atmospheric CO2 under Infrared Light Irradiation

AbstractInfrared light driven photocatalytic reduction of atmospheric CO2 is challenging due to the ultralow concentration of CO2 (0.04 %) and the low energy of infrared light. Herein, we develop a metallic nickel‐based metal–organic framework loaded with Pt (Pt/Ni‐MOF), which shows excellent activity for thermal‐photocatalytic conversion of atmospheric CO2 with H2 even under infrared light irradiation. The open Ni sites are beneficial to capture and activate atmospheric CO2, while the photogenerated electrons dominate H2 dissociation on the Pt sites. Simultaneously, thermal energy results in spilling of the dissociated H2 to Ni sites, where the adsorbed CO2 is thermally reduced to CO and CH4. The synergistic interplay of dual‐active‐sites renders Pt/Ni‐MOF a record efficiency of 9.57 % at 940 nm for converting atmospheric CO2, enables the procurement of CO2 to be independent of the emission sources, and improves the energy efficiency for trace CO2 conversion by eliminating the capture media regeneration and molecular CO2 release.

Greener One-step Synthesis of Novel In Situ Selenium-doped Framework Photocatalyst by Melem and Perylene Dianhydride for Enhanced Solar Fuel Production from CO2.

To minimize the ever-increasing global warming and environmental problems, the conversion of atmospheric CO2 into value-added solar chemicals/fuels is one of the most challenging tasks. As a means to accomplish this, herein we have synthesized first time novel in situ selenium-doped polyimide frameworks (Se-PIFs) photocatalyst via thermal co-polymerization approach between melem (M) and perylene 3, 4, 9, 10-tetracarboxylic dianhydride (PTDA) along with selenium (Se) as a dopant. The Se-PIFs photocatalyst shows outstanding photocatalytic stability and activity for high solar fuel production (HCOOH ~ formic acid) from CO2 . The solar light active Se-PIFs photocatalyst was demonstrating the ~ 10-fold higher photo-conversion of CO2 to formic acid with yields of 250. 6 μmol. The current work is providing a facile and scalable avenue as well as sheds light on creating a new route for in situ judicious design highly efficient Se-PIFs photocatalyst. The outcome is a benchmark instance for the use of selenium-doped polyimide frameworks as a highly practical and efficient solar light active photocatalyst for carrying out the selective production of formic acid from environmental CO2 .

Complex formation of rubisco and rubisco activase

The purpose of this research is to observe the structure of Rubisco and Rubisco Activase (Rca) complex using cryo-EM. Ribulose-1,5-bisphosphate carboxylase oxygenase or Rubisco is an enzyme majorly involved in carbon dioxide fixation, i.e., conversion of atmospheric CO2 by plants to energy-rich, organic carbon such as glucose. Despite being the most abundant protein available, Rubisco is highly inefficient as an enzyme often subjected to inhibition by oxygen and RuBP. The enzyme responsible for inhibitor removal is Rubisco activase (Rca), which has evolved alongside Rubisco as its catalytic chaperone.

N/O-rich multilayered ultramicroporous carbon for highly efficient capture and conversion of CO2 under atmospheric conditions

Porous carbon materials have shown great promise for the efficient capture and conversion of atmospheric CO2 yet remain challenging.

In-situ capture and conversion of atmospheric CO2 into nano-CaCO3 using a novel pathway based on deep eutectic choline chloride-calcium chloride

This study presents a newfangled method and provides a new approach toward capturing-entrapping the toxic and harmful greenhouse gas CO2 and subsequently employing it as a useful precursor for the production of value-added calcite (CaCO3) nanoparticles. All the processes are done in a single system (one-pot and in-situ processing) based on deep eutectic choline chloride-calcium chloride (Calcoline) at mild temperature of 50 °C in direct contact with air. The Calcoline eutectic mixture shows the calcite production yield of 6.2 mg/ml that is reduced up to 22.6% upon recycling. The eutectic mixture provides an interesting all-in-one system acting as carbon dioxide trapper/adsorbent, solvent to solubilize CO2, and reagent to convert solubilized CO2 into pure calcite nanoparticles with average particle size of 30 nm. The featured properties of the developed method including simplicity, recyclability, mobility, affordability, and sustainability make it feasible for large scale applications by which the simultaneous elimination of CO2 from the environment and conversion of it into value added nano-products will be practicable.

The reductive pentose phosphate cycle for photosynthetic CO2 assimilation: enzyme modulation.

The reductive pentose phosphate cycle (Benson-Calvin cycle) is the main biochemical pathway for the conversion of atmospheric CO2 to organic compounds. Two unique systems that link light-triggered events in thylakoid membranes with enzyme regulation are located in the soluble portion of chloroplasts (stroma): the ferredoxin-thioredoxin system and ribulose 1,5-bisphosphate carboxylase/oxygenase-Activase (Rubisco-Activase). The ferredoxin-thioredoxin system (ferredoxin, ferredoxin-thioredoxin reductase, and thioredoxin) transforms native (inactive) glyceraldehyde-3-P dehydrogenase, fructose-1,6-bisphosphatase, sedoheptulose-1,7-bisphosphatase, and phosphoribulokinase to catalytically competent forms. However, the comparison of enzymes reveals the absence of common amino acid sequences for the action of reduced thioredoxin. Thiol/disulfide exchanges appear as the underlying mechanism, but chloroplast metabolites and target domains make the activation process peculiar for each enzyme. On the other hand, Rubisco-Activase facilitates the combination of CO2 with a specific epsilon-amino group of ribulose 1,5-bisphosphate carboxylase/oxygenase and the subsequent stabilization of the carbamylated enzyme by Mg2+, in a reaction that depends on ATP and ribulose 1,5-bisphosphate. Most of these studies were carried out in homogeneous solutions; nevertheless, a growing body of evidence indicates that several enzymes of the cycle associate either with thylakoid membranes or with other proteins yielding supra-molecular complexes in the chloroplast.