Fabrication of a Carbonized Cellulose Nanofibrils/Ti3C2Tx MXene/g-C3N4 Heterojunction for Visible-Light-Driven Photocatalysis.

Photocatalytic degrading pollutants driven by visible-light irradiation has attracted tremendous attention. One strategy of preparing carbonized cellulose nanofibrils/Ti3C2Tx MXene/g-C3N4 (CMCN) as a photocatalyst was developed. The as-prepared CMCN was comprehensively characterized in terms of the chemical composition, chemical and crystal structure, morphology, and photoelectrochemical properties. The CMCN was explored as a photocatalyst and exhibited good photocatalytic performance in degrading MB (96.5%), RhB (95.4%), and TC (86.5%) under visible-light conditions. In addition, the CMCN as a photocatalyst exhibited good reusability and stability. It is found that the incorporation of cellulose nanofibrils provided a high carbon content, a high porosity, and a large specific surface area, enhanced the electron transfer, improved the photocatalytic performance, and ensured a semiconductor with a high stability. It is believed that this study would provide an effective approach to preparing a photocatalyst and broaden the potential application of cellulose nanofibrils in photocatalysis.

Facile synthesis of a bismuth nanostructure with enhanced selectivity for electrochemical conversion of CO2 to formate.

Electrochemically converting carbon dioxide (CO2) to formate offers a promising approach for energy conversion and storage. Bismuth is believed to be one of the promising candidates for CO2 electroreduction, but the poor selectivity and complexity of synthesis limit its real application on a large scale. In this work, a facile one-step-reduction method was developed to prepare a bismuth nanostructure in aqueous solution. Owing to its enhanced reactive sites and exposed crystal plane, the prepared Bi nanostructure exhibits excellent performance for CO2 electroreduction, which reaches the maximum faradaic efficiency for formate as high as 92% at a potential of -0.9 V versus a reversible hydrogen electrode. Additionally, the large current density and remarkable durability also reveal its high intrinsic CO2 electroreduction activity. The density functional theory calculation confirms that the formation of intermediate *OCHO that finally converts to formate is thermodynamically favorable on Bi high-index planes. We anticipate that such a facile synthesis strategy and excellent electrocatalytic performance of the Bi nanostructure will be easy to scale up, realizing its industrialization applications in CO2 electrochemical conversion.