Unexpected high binding energy of CO₂ on CH₃NH₃PbI₃ lead-halide organic–inorganic perovskites via bicarbonate formation

Abstract

The adsorption kinetics of CO2 was experimentally characterized in ultra-high vacuum (UHV). Unexpectedly, high desorption temperatures (640 K, 170 kJ mol-1) were seen. Density functional theory (DFT) calculations suggest the stabilization mechanism: bicarbonate formation in the defected perovskite film due to CO2 and H2O coadsorption.

Hypercrosslinked Polymers as a Photocatalytic Platform for Visible‐Light‐Driven CO2Photoreduction Using H2O

“…Other materials such as ZrO and coal also exhibit increased CO 2 adsorption and/or activation in the presence of co‐adsorbed H 2 O [38–40] . In addition to ensuring the presence of H 2 O molecules close to active sites, we speculate that co‐adsorbed water may also favor CO 2 activation and/or the formation of bicarbonate species and facilitate its photoreduction, as suggested elsewhere for other photocatalysts [41,42] . Nonetheless, further mechanistic studies are required to understand the influence of H 2 O on CO 2 adsorption and the structure‐property relationship for these materials.…”

All-Inorganic CsPbBr3 Nanocrystals: Gram-Scale Mechanochemical Synthesis and Selective Photocatalytic CO2 Reduction to Methane

“…CO 2 can adsorb on Cu-RGO via π–π conjugation interactions and via the formation of surface-bound carbonate on hydroxyl groups (for example at RGO defects or the Cu particle surface) . Moreover, Cu-RGO can have a templating effect during the mechanochemical synthesis, spreading the precursors and eventually increasing the surface area of the final products ,− Further investigation is required on the adsorption mode of CO 2 on CsPbBr 3 and the effect of water vapor, which probably involves the formation of bicarbonates and carbonic acid from surface or subsurface reactions of CO 2 and H 2 O . Very interestingly, vials containing NS-Cu-RGO were opened to expose the sample to the 55–60% relative humidity in the lab air, and no phase change was observed after 8 days, which indicated that the NS-Cu-RGO was relatively more stable in humid conditions than CsPbBr 3 nanosheets alone that decomposed to PbBr 2 and Cs 4 PbBr 6 in the same conditions (Figure S7a,b).…”

“…50 Moreover, Cu-RGO can have a templating effect during the mechanochemical synthesis, spreading the precursors and eventually increasing the surface area of the final products 28,[50][51][52] Further investigation is required on the adsorption mode of CO 2 on CsPbBr 3 and the effect of water vapor, which probably involves the formation of bicarbonates and carbonic acid from surface or subsurface reactions of CO 2 and H 2 O. 53 RGO consisted of a layered structure with typical wrinkled surfaces (Figure S8). The twodimensional RGO nanosheets tended to re-stack when dried due to van der Waals (vdW) interlayer interactions.…”

Regulating the phase stability and bandgap of quasi-2D Dion–Jacobson CsSnI3 perovskite via intercalating organic cations

“…Binding energies between inorganic octahedral layers and organic cations are one of the key factors indicating the electrostatic interaction between ligands and octahedral components. 50,51 Hence, the electrostatic interaction of (ThDMA)Cs n −1 Sn n I 3 n +1 perovskites can be evaluated based on binding energies ( E B ), 52 which is set by:where E (ThDMA)Cs n −1Sn n I3 n +1 , E ThDMA 2+ , and E Cs n −1Sn n I3 n +1 2− refer to the DFT-calculated total energies of (ThDMA)Cs n −1 Sn n I 3 n +1 , ThDMA 2+ and Cs n −1 Sn n I 3 n +1 2− unit cell, respectively; and 4NIONS n represents the total number of atoms of (ThDMA)Cs n −1 Sn n I 3 n +1 perovskite.…”