The lipid droplet (LD) is a cell organelle that has been linked to human metabolic syndromes and that can be exploited for the development of biofuels. The isolation of LDs is crucial for carrying out morphological and biochemical studies of this organelle. In the past two decades, LDs have been isolated from several organisms and investigated by microscopy, proteomics and lipidomics. However, these studies need to be extended to more model organisms, as well as to more animal tissues. Thus, a standard method that can be easily applied to these new samples with the need for minimal optimization is essential. Here we provide an LD isolation protocol that is relatively simple and suitable for a wide range of tissues and organisms. On the basis of previous studies, this 7-h protocol can yield 15-100 μg of protein-equivalent high-quality LDs that satisfy the requirements for current LD research in most organisms.

Atomically dispersed metal and nitrogen co-doped carbon (M-N/C) catalysts hold great promise for electrochemical CO2 conversion. However, there is a lack of cost-effective synthesis approaches to meet the goal of economic mass production of single-atom M-N/C with desirable carbon support architecture for efficient CO2 reduction. Herein, we report facile transformation of commercial carbon nanotube (CNT) into isolated Fe–N4 sites anchored on carbon nanotube and graphene nanoribbon (GNR) networks (Fe-N/CNT@GNR). The oxidization-induced partial unzipping of CNT results in the generation of GNR nanolayers attached to the remaining fibrous CNT frameworks, which reticulates a hierarchically mesoporous complex and thus enables a high electrochemical active surface area and smooth mass transport. The Fe residues originating from CNT growth seeds serve as Fe sources to form isolated Fe–N4 moieties located at the CNT and GNR basal plane and edges with high intrinsic capability of activating CO2 and suppressing hydrogen evolution. The Fe-N/CNT@GNR delivers a stable CO Faradaic efficiency of 96% with a partial current density of 22.6 mA cm–2 at a low overpotential of 650 mV, making it one of the most active M-N/C catalysts reported. This work presents an effective strategy to fabricate advanced atomistic catalysts and highlights the key roles of support architecture in single-atom electrocatalysis.

The pore engineering of microporous metal− organic frameworks (MOFs) has been extensively investigated in the past two decades, and an expansive library of functional groups has been introduced into various frameworks. However, the reliable procurement of MOFs possessing both a targeted pore size and preferred functionality together is less common. This is especially important since the applicability of many elaborately designed materials is often restricted by the small pore sizes of microporous frameworks. Herein, we designed and synthesized a mesoporous MOF based on Zr 6 clusters and tetratopic carboxylate ligands, termed PCN-808. The accessible coordinatively unsaturated metal sites as well as the intrinsic flexibility of the framework make PCN-808 a prime scaffold for postsynthetic modification via linker installation. A linear ruthenium-based metalloligand was successfully and precisely installed into the walls of open channels in PCN-808 while maintaining the mesoporosity of the framework. The photocatalytic activity of the obtained material, PCN-808-BDBR, was examined in the aza-Henry reaction and demonstrated high conversion yields after six catalytic cycles. Furthermore, thanks to the mesoporous nature of the framework, PCN-808-BDBR also exhibits exceptional yields for the photocatalytic oxidation of dihydroartemisinic acid to artemisinin.

Poor electrocatalytic activity and carbon monoxide (CO) poisoning of the anode in Pt-based catalysts are still two major challenges facing direct methanol fuel cells. Herein, we demonstrate a highly active and stable Pt nanoparticle/Mo 2 C nanotube catalyst for methanol electro-oxidation. Pt nanoparticles were deposited on Mo 2 C nanotubes using a controllable atomic layer deposition (ALD) technique. This catalyst showed much higher catalytic activity for methanol oxidation and superior CO tolerance, when compared with those of the conventional Pt/C and PtRu/C catalysts. The experimental evidence from X-ray absorption near-edge structure spectroscopy and scanning transmission X-ray microscopy clearly support a strong chemical interaction between the Pt nanoparticles and Mo 2 C nanotubes. Our studies show that the existence of Mo 2 C not only minimizes the required Pt usage but also significantly enhances CO tolerance and thus improves their durability. These results provide a promising strategy for the design of highly active next-generation catalysts.

Density functional theory (DFT) calculation is carried out to access the band structure and density of states (DOS) based on the models of TiO2 nanoparticle, nanotube, and nanosheet, predicting the order of the photocatalytic activity for three different nanostructures. Sol–gel method and hydrothermal method are used to achieve desired morphologies: nanoparticles, nanotubes, and nanosheets (fragmentized nanotubes). The photocatalytic activity ranks in the order of nanosheets > nanotubes > nanoparticles, which is consistent with theoretical prediction. It was revealed that the enlargement of band gap is caused by the quantum confinement effect; the prolonged lifetime of photogenerated electrons and increased specific surface areas are dependent on the morphology of the nanostructure. All these factors contribute to the improvement of the photocatalytic activity for nanostructures. Our results can guide the design and selection of low-dimensional nanomaterials with desired morphology and improved photoelectric functional properties, which can be used in many fields, such as solar cells, photocatalysis, and photosynthesis.

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Increasing demand for food due to rapid population growth has exerted unprecedented pressure on the global agricultural industry. Agrochemicals are widely used to ensure productivity, leading to the prevalence of legacy and emerging agricultural chemicals in the environment, most of which are toxic and persistent. Metal−organic frameworks (MOFs) as a group of novel photocatalytic materials with ultrahigh porosity and tunability have demonstrated high potential for efficient removal of these recalcitrant pollutants. This critical review aims to present the potential of MOF-catalyzed photodegradation of pesticides and antibiotics. Initially, the capabilities of different MOF-based composites to harvest visible light are compared. Examples include MOFs combined with bismuth oxyhalides (BiOX) and graphite oxide (GO). Mechanisms involved in MOF-induced photocatalytic processes such as electron−hole (e − /h + ) separation, generation of reactive species, and degradation pathways of representative pollutants as well as impacts of water chemistry are illustrated in detailed. Research on applying MOF-catalyzed processes is largely in progress, and many more studies with greater mechanistic evaluation are needed to fully assess the potential of such processes to depollute water.