Extending the π-Conjugated System in Conjugated Microporous Polymers to Modulate Excitonic Effects for Metal-Free Selective CO2 Photoreduction to CH4 DOI

Meng Fanyu,

Juan Wang, Minghui Chen

et al.

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(18), P. 12142 - 12152

Published: Aug. 31, 2023

Photocatalytic CO2 reduction into CH4 is an appealing approach to alleviate the current energy and environmental crisis; however, achieving high selectivity conversion efficiency still remains challenging. The rational design of photocatalysts for adsorption activation thus crucial. Here, we designed synthesized two redox-active truxene-based conjugated microporous polymers linked by thiazolo[5,4-d]thiazole metal-free photocatalytic CH4. Significantly, optimized polymer with extended π-conjugated system, denoted Tx-TzTz-CMP-2, presented a higher production rate 300.6 μmol g–1 h–1 71.2% without any metal cocatalyst photosensitizer, which outperformed most previously reported photocatalysts. Experimental theoretical investigations revealed that introducing phenyl as π-bridge extending electron delocalization system might effectively minimize exciton binding energy, thereby boosting intramolecular charge transfer separation abilities. Meanwhile, N-site thiazole unit acted reservoir catalytic center activating adsorbed forming subsequent hydrogenation. This work highlights significance in improve activity photoreduction

Language: Английский

Ultrathin Nanosheet Assembled Multishelled Superstructures for Photocatalytic CO2 Reduction DOI

Fengliang Wang,

Ruiqi Fang, Xin Zhao

et al.

ACS Nano, Journal Year: 2022, Volume and Issue: 16(3), P. 4517 - 4527

Published: March 4, 2022

Solar-driven conversion of CO2 is considered an efficient way to tackle the energy and environmental crisis. However, photocatalytic performance severely restricted due insufficient accessible active sites inhibited electron transfer efficiency. This work demonstrates a general in situ topological transformation strategy for integration uniform Co-based species fabricate series multishelled superstructures (MSSs) conversion. Thorough characterizations reveal obtained MSSs feature ultrathin nanosheet assembled polyhedral structures with tunable shell numbers, inner cavity sizes, compositions. The increase spatial density while maintaining their high accessibility. Further, nanosheets also facilitate photogenerated electrons. As result, ZnCo bimetallic hydroxide featuring quadruple-shell hollow structure (ZnCo-OH QUNH) exhibits efficiency toward reduction CO evolution rate 134.2 μmol h-1 apparent quantum yield 6.76% at 450 nm. quasi spectra theoretical calculations disclose that Co ZnCo-OH QUNH act as highly centers stabilize COOH* intermediate, Zn play role adsorption [Ru(bpy)3]2+ molecules.

Language: Английский

Citations

71
Electronic Transmission Channels Promoting Charge Separation of Conjugated Polymers for Photocatalytic CO2 Reduction with Controllable Selectivity DOI

Chi Xu,

Zhi‐An Lan, Qian Chen

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(22)

Published: April 3, 2023

Conjugated polymers (CPs) represent a promising platform for photocatalytic CO2 fixation owing to their suitable band structures that meet the requirements of reduction potential value-added fuels. However, performance CPs is rather restrained by low charge transfer efficiency. Herein, we rationally designed three with more delocalized electronic transmission channel and planar molecular structure, which are regarded evidently reduce exciton binding energy (Eb ) accelerate internal process. Besides, assembly electron-output "tentacles" cocatalysts on surface could effectively facilitate interfacial electron delivery. Accordingly, optimal P-2CN exhibits an apparent quantum yield 4.6 % at 420 nm CO. Further adjusting amounts cyano groups cocatalysts, CO selectivity be obtained in range 0-80.5 %.

Language: Английский

Citations

71
Ni–Co Bimetallic Hydroxide Nanosheet Arrays Anchored on Graphene for Adsorption‐Induced Enhanced Photocatalytic CO2 Reduction DOI
Mengmeng Wang, Dongyun Chen, Najun Li

et al.

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(28)

Published: May 10, 2022

Photocatalytic CO2 reduction can be implemented to use , a greenhouse gas, as resource in an energy-saving and environmentally friendly way, which suitable catalytic materials are required achieve high-efficiency catalysis. Insufficient accessible active sites on the catalyst surface inhibited electron transfer severely limit photocatalytic performance. Therefore, porous aerogels constructed from composites comprising different ratios of Ni-Co bimetallic hydroxide (Nix Coy ) grown reduced graphene oxide (GR) into hierarchical nanosheet-array structure using facile situ growth method. Detailed characterization shows that this exposes numerous for enhanced adsorption-induced reduction. Moreover, under synergistic effect hydroxide, adsorption capacity well charge-carrier separation excellent. As result, Ni7 Co3 -GR exhibits highly improved performance when compared with recently reported values, high CO release rate 941.5 µmol h-1 g-1 selectivity 96.3% during . This work demonstrates new strategy designing nanocomposites abundant structures.

Language: Английский

Citations

70
Engineering Single Cu Sites into Covalent Organic Framework for Selective Photocatalytic CO2 Reduction DOI

Yize Zhang,

Lili Cao, Guoyi Bai

et al.

Small, Journal Year: 2023, Volume and Issue: 19(22)

Published: March 3, 2023

Photocatalytic CO2 conversion into value-added chemicals is a promising route but remains challenging due to poor product selectivity. Covalent organic frameworks (COFs) as an emerging class of porous materials are considered candidates for photocatalysis. Incorporating metallic sites COF successful strategy realize high photocatalytic activities. Herein, 2,2'-bipyridine-based bearing non-noble single Cu fabricated by chelating coordination dipyridyl units reduction. The coordinated not only significantly enhance light harvesting and accelerate electron-hole separation also provide adsorption activation molecules. As proof concept, the Cu-Bpy-COF representative catalyst exhibits superior activity reducing CO CH4 without photosensitizer, impressively, selectivity can be readily modulated changing reaction media. Experimental theoretical results reveal crucial role in promoting photoinduced charge solvent effect regulating selectivity, which provides important sight onto design photocatalysts selective photoreduction.

Language: Английский

Citations

65
Extending the π-Conjugated System in Conjugated Microporous Polymers to Modulate Excitonic Effects for Metal-Free Selective CO2 Photoreduction to CH4 DOI

Meng Fanyu,

Juan Wang, Minghui Chen

et al.

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(18), P. 12142 - 12152

Published: Aug. 31, 2023

Photocatalytic CO2 reduction into CH4 is an appealing approach to alleviate the current energy and environmental crisis; however, achieving high selectivity conversion efficiency still remains challenging. The rational design of photocatalysts for adsorption activation thus crucial. Here, we designed synthesized two redox-active truxene-based conjugated microporous polymers linked by thiazolo[5,4-d]thiazole metal-free photocatalytic CH4. Significantly, optimized polymer with extended π-conjugated system, denoted Tx-TzTz-CMP-2, presented a higher production rate 300.6 μmol g–1 h–1 71.2% without any metal cocatalyst photosensitizer, which outperformed most previously reported photocatalysts. Experimental theoretical investigations revealed that introducing phenyl as π-bridge extending electron delocalization system might effectively minimize exciton binding energy, thereby boosting intramolecular charge transfer separation abilities. Meanwhile, N-site thiazole unit acted reservoir catalytic center activating adsorbed forming subsequent hydrogenation. This work highlights significance in improve activity photoreduction

Language: Английский

Citations

62