CO2 -Mediated Photocatalytic Chlorine Production Over Bismuth Oxychloride in Chloride Solution.

As one of the most commonly bulky chemicals, chlorine is conventionally manufactured by electrolysis of NaCl solution in the chlor-alkali process, which requires a huge supply of electrical energy. The photocatalytic route to produce chlorine by using solar energy and NaCl solution offers a promising strategy to reduce energy consumption and bring economic benefits. Herein, it was found that the introduction of CO2 would enhance the productivity of Cl2 from 8.24 µmol⋅h-1 to 39.6 µmol⋅h-1 in NaCl solution over BiOCl. Experimental studies reveal that the CO2 species (CO3 2- ) entered into the crystal texture of BiOCl and the interlayer space between [Bi2 O2 ]2+ slabs were increased and distorted, accelerating the cycle of Cl species. Besides, the cycle of carbonate species also existed and accelerated the reaction efficiency of Cl- oxidation to Cl2 . This work provides a new feasible method of using abundant CO2 resources to accelerate the process of chlorine production via photocatalysis.

Carbon Dioxide Anion Radicals Assisted Highly Efficient Photocatalytic H2O2 Production over Bi(C2O4)OH.

Carbon dioxide anion radical (CO2•-) can act as a versatile single electron reductant, but its generation pathways are quite limited. Herein, we demonstrate that oxalic acid (OA) could be effectively and continuously utilized to produce CO2•- over Bi(C2O4)OH, a novel photocatalyst, under light irradiation. Bi(C2O4)OH would proceed with self-redox reactions under the light irradiation producing CO2•-, through the oxidation of C2O42-. OA in the solution could recoordinate with Bi3+, thus maintaining the structure of the photocatalysts and the stability of the reactions. Benefiting from the fast reaction between CO2•- and O2 in forming •O2-, hydrogen peroxide (H2O2) would be efficiently produced (219.0 µmol/h). This study proposes a novel approach for harnessing OA containing wastewater and explores its potential application in the efficient production of H2O2.

Efficient One-Pot Synthesis of 2,5-Furandicarboxylic Acid from Sugars over Polyoxometalate/Metal-Organic Framework Catalysts.

Converting extensive sugars into value-added 2,5-furandicarboxylic acid (FDCA) has been considered to be a promising approach to developing sustainable substitutes for chemicals from fossil resources. The complicated conversion processes involved multiple cascade reactions and intermediates, which made the design of efficient multifunction catalysts challenging. Herein, we developed a catalyst by introducing phosphotungstic acid (PW) and Co sites into the UiO-66, which achieved a one-pot cascade conversion of fructose-to-FDCA with high conversion (>99 %) and yield (94.6 %) based on the controllable Lewis/Brønsted acid sites and redox sites. Controlled experiments and detailed characterizations show that the multifunctional PW/UiO(Zr, Co) catalysts successfully affords the direct synthesis of FDCA from fructose via dehydration and selective oxidation in the one-pot reaction. Additionally, the MOF catalysts could also efficiently convert various sugars into FDCA, which has broad application prospects. This study provides new strategies for designing multifunctional catalysts to achieve efficient production of FDCA from biomass in the one-pot reaction.