A review on photo-thermal catalytic conversion of carbon dioxide

The conversion of carbon dioxide into value-added products is of great industrial and environmental interest. However, as carbon dioxide is relatively stable, the input energy required for this conversion is a significant limiting factor in the system's performance. By utilising energy from the sun, through a range of key routes, this limitation can be overcome. In this review, we present a comprehensive and critical overview of the potential routes to harvest the sun's energy, primarily through solar-thermal technologies and plasmonic resonance effects. Focusing on the localised heating approach, this review shortlists and compares viable catalysts for the photo-thermal catalytic conversion of carbon dioxide.Further, the pathways and potential products of different carbon dioxide conversion routes are outlined with the reverse water gas shift,methanation, and methanol synthesis being of key interest. Finally, the challenges in implementing such systems and the outlook to the future are detailed.

Truth and False-carbon Dioxide Mitigation Technologies

Research progress is required to be enhanced for those storage technologies which store CO_(2)fast and permanently.However,temporary storage technologies importance cannot be denied to immediately reduce global warming and reduce higher CO_(2)concentration in the atmosphere.Continuous CO_(2)storage facilities,semi-batch and batch pilot plants deemed necessary to build for future survival of the earth planet.Membranes can be used to separate CO_(2)from common flue gases followed by mineral carbonation to convert CO_(2)into stable carbonates.Modifications in cement industry,coal fired power plants,fertilizer industries and other chemical process industries appears essential.

Correlation between impedance spectroscopy and bubble-induced mass transport in the electrochemical reduction of carbon dioxide

In the electrochemical conversion of carbon dioxide, high currents need to be employed to obtain large production rates, thus implying that mass transport of reactants and products is of crucial importance.This aspect can be investigated by employing a model that depicts the local environment for the reduction reactions. Simultaneously, electrochemical impedance spectroscopy, despite being a versatile technique, has rarely been adopted for studying the mass transport features during the carbon dioxide(CO_(2))electroreduction. In this work, this aspect is deeply analyzed by correlating the results of impedance spectroscopy characterization with those obtained by a bubble-induced mass transport modeling under controlled diffusion conditions on a gold rotating disk electrode. The effects of potential and rotation rate on the local environment are also clarified. In particular, it has been found that CO_(2) depletion occurs at high kinetics when the rotation is absent, giving rise to an increment of the competing hydrogen evolution reaction. This feature reflects in an enlargement of the diffusion resistance, which overcomes the charge transport one.

Enhancing cathode performance for CO2 electrolysis with Ce0.9M0.1O2-δ（M=Fe, Co, Ni） catalysts in solid oxide electrolysis cell

Electrochemical conversion with solid oxide electrolysis cells is a promising technology for CO2 utilization and simultaneously store renewable energy.In this work,Ce0.9M0.1O2-δ(CeM,M=Fe,Co,Ni)catalysts are infiltrated into La0.6Sr0.4Cr0.5Fe0.5O3-δ-Gd0.2Ce0.8O2-δ(LSCr Fe-GDC)cathode to enhance the electrochemical performance for CO2 electrolysis.CeCo-LSCrFe-GDC cell obtains the best performance with a current density of 0.652 A cm^-2,followed by CeFe-LSCrFe-GDC and CeNi-LSCrFe-GDC cells with the value of 0.603 and 0.535 A cm^-2,respectively,about 2.44,2.26 and 2.01 times higher than that of the LSCrFe-GDC cell at1.5 V and 800℃.Electrochemical impedance spectra combined with distributions of relaxed times analysis shows that both CO2 adsorption process and the dissociation of CO2 at triple phase boundaries are accelerated by Ce M catalysts,while the latter is the key rate-determining step.

Fluorinated Covalent Organic Frameworks Coupled with Molecular Cobalt Cocatalysts for Efficient Photocatalytic CO_(2)Reduction

The combination of covalent organic framework(COF)photosensitizers with molecular cocatalysts is a promising avenue for photocatalytic carbon dioxide(CO_(2))reduction.Here,a series of isostructural COFs was synthesized using linkers of different lengths,with or without partial fluorination.These COFs were investigated for photocatalytic CO_(2)reduction under visible-light irradiation when combined with cobalt(II)bipyridine complexes as a cocatalyst.Fluorination was found to enhance both CO_(2)affinity and catalytic activity,and a partially fluorinated COF,FBP-COF,achieved the highest CO_(2)-to-CO conversion efficiency,showing a carbon monoxide(CO)generation rate of 2.08 mmol h−1 g−1 and a 90%CO selectivity.FBP-COF also showed good stability under sacrificial conditions,generating CO for 50 h with a turnover number of 91.5.This activity is much higher than a homogeneous system using ruthenium bipyridine complexes as the photosensitizer combined with the same cobalt bipyridine complexes.

The energy-environment nexus:aerosol science and technology enabling solutions

Energy issues are important and consumption is slated to increase across the globe in the future.The energy-environment nexus is very important as strategies to meet future energy demand are developed.To ensure sustainable growth and development,it is essential that energy production is environmentally benign.There are two temporal issues—one that is immediate,and needs to address the environmental compliance of energy generation from fossil fuel sources;and second that is the need to develop newer alternate and more sustainable approaches in the future.Aerosol science and technology is an enabling discipline that addresses the energy issue over both these time scales.The paper is a review of aspects of aerosol science and engineering that helps address carbon neutrality of fossil fuels.Advanced materials to meet these challenges are discussed.Future approaches to effective harvesting of sunlight that are enabled by aerosol studies are discussed.

Highly active electrocatalytic CO_(2) reduction with manganese N-heterocyclic carbene pincer by para electronic tuning

Electronic tuning by para substitutions was explored to achieve a highly active manganese N-heterocyclic carbene pincer complex for the selective electrocatalytic reduction of CO_(2)to CO.[MnCNC^(OMe)]BF_(4)(L2-Mn)bearing an electron-donating group(-OMe)showed high activity with 63×catalytic current enhancement,average Faradaic efficiency of 104%,and a TOF_(max) value of 26,127 s^(-1),which is 127 times higher than that of unsubstituted[MnCNCH]Br(L1-Mn)reported previously.In contrast,the electron-withdrawing group(-COOMe)in[MnCNC^(CO^(OMe))]PF_(6)(L3-Mn)inhibited the electrocatalytic activity.Ambient Brønstic acid,however,suppressed the activity of L2-Mn probably due to the protonation of the-OMe group.These findings indicate a potential electronic tuning strategy to improved manganese N-heterocyclic carbene catalysts for CO_(2)reduction.