Conversion of Biomasses and Copper into Catalysts for Photocatalytic CO₂ Reduction

Abstract

The rapid increase of CO2 in the atmosphere has caused serious environmental problems. Burning of biomass wastes increases the content of CO2 in the environment. Herein, we propose a new strategy to convert biomass into photocatalysts for artificial CO2 reduction. Using a hydrothermal method, carbohydrates from biomass can be converted into hydrothermal carbonaceous carbon (HTCC). The HTCC consists of plenty of sp2-hybridized structures, which are capable of absorbing solar light for photocatalytic CO2 reduction. Furthermore, with the addition of Cu cocatalysts, higher activity can be obtained for CO2 reduction. The activity of Cu-HTCC is 32 and 1.7 times higher than that of commercial TiO2 and pure HTCC, respectively. This method provides a new strategy of trash to treasure, which converts biomass waste into photocatalysts for CO2 reduction.

Liquefiable biomass-derived porous carbons and their applications in CO2capture and conversion

“…Currently, the biomass-derived porous carbons (BPCs) are more environmentally friendly and neutral than coal-and petroleum-based carbon materials, 10 and a large number of BPCs have been used for CO 2 capture [16][17][18] and conversion. [19][20][21] Precursors to prepare BPCs include coconut shell, 22,23 wood, 24,25 sludge, 26,27 glucose, 28,29 etc. Most of the plant biomass is in solid-state, such as straw, fruit shell, etc.…”

“…34,50,52,55,58,[60][61][62][63] In addition, in the liquid phase, the porous carbon can be uniformly doped with heteroatoms at the molecular level, which could facilitate the introduction of alkaline functional groups on the adsorbent for CO 2 capture 28,64 and the uniform distribution of the active sites of the catalyst for CO 2 conversion. 20,21 Furthermore, LBPs can be used to prepare porous carbon materials with various morphologies, including spherical, 28,50,54,59,[65][66][67][68] hollow spherical, 34,69 flower-like, 38 sheet-like, 44 column, 56,62,70 and chunk. 46,[71][72][73] Thus, the active site is more exposed, and porous carbon with different morphologies is conducive to adapt to various CO 2 conversion products with different molecular sizes.…”

Recent Progress of Perovskite Oxide in Emerging Photocatalysis Landscape: Water Splitting, CO₂ Reduction, and N₂ Fixation

“…As one of our main energy sources, fossil fuels have indeed accelerated the process of human community development, while carbon dioxide became the main greenhouse gas at the same time [163][164][165][166][167][168] . In recent years, the inexorable rise of carbon dioxide level in the atmosphere has already exceeded 400 × 10 −6 and the concentration of CO2 has increased at a rate higher than that of 2 × 10 −6 every year, highlighting the need for reducing the present CO2 emissions [168][169][170][171][172][173] . Therefore, the production of valuable chemicals or fuels using the greenhouse gas, CO2 as a carbon source has been considered as a promising solution in dealing with the critical issues of energy shortages, clean energy production, and maintaining the normal carbon cycle to get the global environment back on track 169,[174][175][176][177][178][179][180][181][182] .…”

Bifunctional metal–organic frameworks afforded by postsynthetic modification for efficient cycloaddition of CO2 and epoxides

“…In this context, CO 2 conversion becomes a very active area of sustainable chemistry because it can acquire value-added chemical products. [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] Among these conversion, the CO 2 cycloaddition from CO 2 and propylene oxide (PO) to propylene carbonate (PC) is of great interest. [24][25][26][27][28][29][30][31][32] The conversion shows 100% atom economy, and the products (PC) are widely used as electrolytes, polar solvent, pharmaceuticals, and intermediates in some organic reactions.…”