Emerging materials for lowering atmospheric carbon

Abstract

CO 2 emissions from anthropogenic sources and the rate at which they increase could have deep global ramifications such as irreversible climate change and increased natural disasters. Because greater than 50% of anthropogenic CO 2 emissions come from small, distributed sectors such as homes, offices, and transportation sources, most renewable energy systems and on-site carbon capture technologies for reducing future CO 2 emissions cannot be effectively utilized. This problem might be mediated by considering novel materials and technologies for directly capturing/removing CO 2 from air. However, compared to materials for capturing CO 2 at on-site emission sources, materials for capturing CO 2 directly from air must be more selective to CO 2 , and should operate and be stable at near ambient conditions. In this review article, we briefly summarize the recent devlopments in materials for capturing carbon dioxide directly from air. We discuss the challenges in this field and offer a perspective for developing the current state-ofart and also highlight the potential of a few recent discoveries in materials science that show potential for advanced application of air capture technology.

An air CO2 capture system based on the passive carbonation of large Ca(OH)2 structures

“…Direct CO 2 capture from air (DAC), combined with permanent CO 2 storage, is one of the negative emission technologies (NETs) that may be needed in the future to limit global warming to 1.5 C. 1,2 The rst conceptual designs of DAC systems were proposed 20 years ago, 3 and research into novel concepts and materials is still continuing today. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] The direct capture of CO 2 from air requires vast contacting surfaces with a great affinity and selectivity towards CO 2 (i.e. through a gas-liquid interface, the internal surface of a solid sorbent or through a membrane).…”

“…8,16 Adsorbent solids with a high selectivity for CO 2 , such as amines supported on porous materials, ion-exchange resins, metalorganic frameworks, zeolites or activated carbons, have also been explored. 8,9,17,18 Other gas-solid contact options are membranes combined with KOH solutions, 19 dispersed amines or ion-exchange resins. 20 An entirely different approach is to extract CO 2 from large ows of seawater by electrodialysis, aer which the water is returned to the ocean to reabsorb more CO 2 from the air.…”

Hierarchical TiO2:Cu2O Nanostructures for Gas/Vapor Sensing and CO2 Sequestration

“…Efforts to monitor air quality and improve building energy efficiency necessitate the development of efficient adsorbent materials and structures for carbon dioxide sensing and sequestration. 1,2 Commercial CO 2 gas sensors that rely on infrared absorptiometry or fluorescence/absorbance signatures of a pH indicator exhibit fast response times and high sensitivities but often suffer from degradation by photobleaching, interference due to variable humidity, and only operate under a limited range of CO 2 concentrations. 3,4 A broad range of new high-surface-area materials, including metal−organic frameworks and microporous and heteroatomactivated carbon have been explored for carbon capture and sensor applications with the highest gas adsorption capacity and minimum response demonstrated for amine-modified surfaces.…”

“…3,4 A broad range of new high-surface-area materials, including metal−organic frameworks and microporous and heteroatomactivated carbon have been explored for carbon capture and sensor applications with the highest gas adsorption capacity and minimum response demonstrated for amine-modified surfaces. 1,2,5 A room temperature ionic liquid (RTIL) has recently been explored as a "green" alternative for CO 2 reaction and separation processes in place of traditional volatile organic compounds that often emit toxic vapors. 6,7 The high solubility of CO 2 in RTILs results from formation of weak Lewis acid−base interactions between the CO 2 electron-pair acceptor and electron-pair donor anion of the RTIL.…”

“…Efforts to monitor air quality and improve building energy efficiency necessitate the development of efficient adsorbent materials and structures for carbon dioxide sensing and sequestration. , Commercial CO 2 gas sensors that rely on infrared absorptiometry or fluorescence/absorbance signatures of a pH indicator exhibit fast response times and high sensitivities but often suffer from degradation by photobleaching, interference due to variable humidity, and only operate under a limited range of CO 2 concentrations. , A broad range of new high-surface-area materials, including metal–organic frameworks and microporous and heteroatom-activated carbon have been explored for carbon capture and sensor applications with the highest gas adsorption capacity and minimum response demonstrated for amine-modified surfaces. ,, A room temperature ionic liquid (RTIL) has recently been explored as a “green” alternative for CO 2 reaction and separation processes in place of traditional volatile organic compounds that often emit toxic vapors. , The high solubility of CO 2 in RTILs results from formation of weak Lewis acid–base interactions between the CO 2 electron-pair acceptor and electron-pair donor anion of the RTIL. − The strength of the RTIL–CO 2 interaction can be tuned by chemical modification of the ionic liquid structure, leading to improved capacity, selectivity, and reversibility of CO 2 . − …”