The utilization of solar energy to produce hydrogen from water is showing increased importance and desirability in the field of artificial photosynthesis to produce clean and sustainable fuels. In a ...typical three‐component dye‐sensitized semiconductor system for photocatalysis, the dye sensitizer plays an essential role of energy antenna for harvesting visible light and promoting the reduction reaction to generate hydrogen. In recent decades, a lot of attention has focused on metal‐free organic sensitizers, which have the advantages of low cost, high molar extinction coefficient, good modifiability and, most importantly, ability to avoid the use of noble metal ions. This Review enumerates the design strategies, specific properties and photocatalytic performances of metal‐free sensitizers in the past 30 years and concludes their evolution process. The advantages of different types of metal‐free sensitizers are highlighted and the instructively enlightening experiences are systematic summarized.
Learning from the past: In the past 30 years diverse types of metal‐free dyes have been developed and applied in dye‐sensitized semiconductor photocatalysts for visible‐light‐driven hydrogen production from water. This Review retrospects the development history and tendency of metal‐free dyes, in which the design strategies, structures, properties and photocatalytic performances are enumerated and their structure‐activity relationships are summarized systematically.
To achieve high performed zinc metal batteries, it is imperative to address the issues of dendrite growth and the side‐reactions occurring at the Zn anode, particularly when the batteries are ...operated at high current densities and high temperature. Herein, a flexible and dendrite‐free Zn metal anode (AgNPs@CC/Zn), which is prepared by inkjet printing silver nanoparticles on a 3D carbon matrix, is reported. Experimental observations and DFT calculation reveal that the Ag nanoparticles can work as heterometallic seeds for zinc deposition, and thus simultaneously improve the zincophilicity and thermal conductivity of the carbon matrix. This not only lowers the Zn nucleation overpotential and guides the uniform Zn nucleation but also promotes the reversible zinc stripping/plating via AgZn alloying/de‐alloying reactions. As a result, the AgNPs@CC/Zn anode presents low voltage hysteresis of 80 mV and superior cycling over 480 h at a high current density of 10 mA cm−2. The AgNPs@CC/Zn anode can enable full cells with exceptional cyclic stability and enhanced high‐temperature endurance. Furthermore, the foldable pouch cell using the AgNPs@CC/Zn anode exhibits high capacity retention regardless of different deformation status. This work demonstrates the promising potential of inkjet printing technology in developing 3D dendrite‐free zinc anode for foldable and heat‐resistant zinc batteries.
A flexible and dendrite‐free Zn metal anode is prepared by inkjet printing silver nanoparticles on a 3D carbon matrix, boosting electrochemical performance of zinc metal batteries. The Ag nanoparticles as heterometallic seeds can promote reversible zinc stripping/plating via AgZn alloying/de‐alloying reactions and improve the zincophilicity and thermal conductivity of the carbon matrix.
Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes ...(MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, along with frequent horizontal gene transfer of mcr genes between alkanotrophs. Analysis of all mcr-containing archaeal MAGs/genomes suggests a hydrothermal origin for these microorganisms based on optimal growth temperature predictions. These results also suggest methane/alkane oxidation or methanogenesis at high temperature likely existed in a common archaeal ancestor.
A highly robust hybrid material based on calixarene dye (HO-TPA) and titanium dioxide with a micro/mesoporous structure and a large surface area (denoted as HO-TPA–TiO2) has been prepared by a facile ...sol–gel method. When Pt nanoparticles (Pt NPs) or fac-Re(4,4′-disphosphonic acid-2,2′-bipyridine)(CO)3Cl (ReP) as co-catalysts are introduced onto the hybrids, respectively, the two hybrid systems can display dual-functional photocatalytic properties. Under visible-light irradiation, the optimized Pt/HO-TPA–TiO2 system exhibits high hydrogen production activity (618.3 mmol g−1 h−1 based on Pt mass) and performs with excellent stability even after being used for 15 times (a turnover number of 6417 after 75 h). On the other hand, the optimum ReP/HO-TPA–TiO2 material displays persistent photocatalysis of CO2 reduction to CO and gives a turnover number of 534 over 26 h (854.4 mmol g−1 based on ReP mass), which is one of the highest among all the reported heterogeneous catalytic systems under visible light. The high activity and stability of the HO-TPA–TiO2 based hybrid materials can be attributed to the stable coordination linkage and efficient electron transfer between HO-TPA and micro/mesoporous TiO2. The current study offers inspiration for the design and application of new multi-functional organic–inorganic hybrid systems for efficient photocatalysis.
An acid‐free N‐nitrosation/nitration of the N−H bonds in secondary amines with Fe(NO3)3 ⋅ 9H2O as the nitroso/nitro source through an electrocatalyzed radical coupling reaction was developed. Cyclic ...aliphatic amines and N‐heteroaromatic compounds were N‐nitrosated and N‐nitrated, respectively, under mild conditions. Control and competition experiments, as well as kinetic studies, demonstrate that N‐nitrosation and N‐nitration involve two different radical reaction pathways involving N+ and N. radicals. Moreover, the electrocatalysis method enables the preferential activation of the N−H bond over the electrode and thus provides high selectivity for specific N atoms. Finally, this strategy exhibits a broad scope and provides a green and straightforward approach to generate useful N‐nitroso/nitro compounds in good yields.
The severe performance degradation of high‐capacity Li−O2 batteries induced by Li dendrite growth and concentration polarization from the low Li+ transfer number of conventional electrolytes hinder ...their practical applications. Herein, lithiated Nafion (LN) with the sulfonic group immobilized on the perfluorinated backbone has been designed as a soluble lithium salt for preparing a less flammable polyelectrolyte solution, which not only simultaneously achieves a high Li+ transfer number (0.84) and conductivity (2.5 mS cm−1), but also the perfluorinated anion of LN produces a LiF‐rich SEI for protecting the Li anode from dendrite growth. Thus, the Li−O2 battery with a LN‐based electrolyte achieves an all‐round performance improvement, like low charge overpotential (0.18 V), large discharge capacity (9508 mAh g−1), and excellent cycling performance (225 cycles). Besides, the fabricated pouch‐type Li–air cells exhibit promising applications to power electronic equipment with satisfactory safety.
A novel design principle of polymerization and fluorination for salt anions has been proposed and lithiated Nafion (LN) was suggested as a representative soluble lithium salt for the polyelectrolyte solution to improve the Li+ transfer number and produce a LiF‐rich solid electrolyte interface (SEI). Furthermore, the perfluorinated backbone of LN delivers the polyelectrolyte solution low flammability. Thus, making the Li−O2 batteries realize all‐round performance amelioration.
N6‐Methyladenosine (m6A) is a important process regulating gene expression post‐transcriptionally. Programmed death ligand 1 (PD‐L1) is a major immune inhibitive checkpoint that facilitates immune ...evasion and is expressed in tumor cells. In this research we discovered that Wilms' tumor 1‐associated protein (WTAP) degradation caused by ubiquitin‐mediated cleavage in cancer cells (colorectal cancer, CRC) under hypoxia was inhibited by Pumilio homolog 1 (PUM1) directly bound to WTAP. WTAP enhanced PD‐L1 expression in a way that was m6A‐dependent. m6A “reader,” Insulin‐like growth factor 2 mRNA‐binding protein 2 (IGF2BP2) identified methylated PD‐L1 transcripts and subsequently fixed its mRNA. Additionally, we found that T‐cell proliferation and its cancer cell‐killing effects were prevented by overexpression of WTAP in vitro and in vivo. Overexpression prevented T cells from proliferating and killing CRC by maintaining the expression of PD‐L1. Further evidence supporting the WTAP–PD‐L1 regulatory axis was found in human CRC and organoid tissues. Tumors with high WTAP levels appeared more responsive to anti‐PD1 immunotherapy, when analyzing samples from patients undergoing treatment. Overall, our findings demonstrated a novel PD‐L1 regulatory mechanism by WTAP‐induced mRNA epigenetic regulation and the possible application of targeting WTAP as immunotherapy for tumor hypoxia.
Our findings demonstrated a novel PD‐L1 regulatory mechanism by WTAP‐induced mRNA epigenetic regulation and a possible application of targeting WTAP as immunotherapy for tumor hypoxia.
The bean bug (Riptortus pedestris) causes great economic losses of soybeans by piercing and sucking pods and seeds. Although R. pedestris has become the focus of numerous studies associated with ...insect–microbe interactions, plant–insect interactions, and pesticide resistance, a lack of genomic resources has limited deeper insights. Here, we report the first R. pedestris genome at the chromosomal level using PacBio, Illumina, and Hi‐C technologies. The assembled genome was 1.080 Gb in size with a contig N50 of 2.882 Mb. More than 96.3% of the total genome bases were successfully anchored to six unique chromosomes. Genome resequencing of male and female individuals and chromosomic staining demonstrated that the sex chromosome system of R. pedestris is XO, and the shortest chromosome is the X chromosome. In total, 19,026 protein‐coding genes were predicted, 18,745 of which were validated as being expressed. Temporospatial expression of R. pedestris genes in six tissues and 37 development stages revealed 4,657 and 7,793 genes mainly expressed in gonads and egg periods, respectively. Evolutionary analysis demonstrated that R. pedestris and Oncopeltus fasciatus formed a sister group and split ∼80 million years ago (Mya). Additionally, a 5.04 Mb complete genome of symbiotic Serratia marcescens Rip1 was assembled, and the virulence factors that account for successful colonization in the host midgut were identified. The high‐quality R. pedestris genome provides a valuable resource for further research, as well as for the pest management of bug pests.
Studies have reported inconsistent results about the risk of incident chronic kidney disease (CKD) in people with metabolically healthy obesity (MHO). We designed this systematic review and ...meta-analysis to evaluate the risk of developing CKD in people with MHO and metabolically unhealthy normal weight (MUNW). We used a predefined search strategy to retrieve eligible studies from multiple databases up to June 20, 2022. Random-effects model meta-analyses were implied to estimate the overall hazard ratio (HR) of incident CKD in obesity phenotypes. Eight prospective cohort studies, including approximately 5 million participants with a median follow-up ranging between 3 and 14 years, were included in this meta-analysis. Compared to the metabolically healthy normal weight (MHNW), the mean differences in cardiometabolic and renal risk factors in MHO, MUNW, and metabolically unhealthy obesity (MUO) were evaluated with overall HR of 1.42, 1.49, and 1.84, respectively. Compared to MHNW, the mean estimated glomerular filtration rate (eGFR) and high-density lipoprotein (HDL) were significantly lower, and low-density lipoprotein (LDL), blood pressure, blood glucose, and triglycerides were higher in MHO and MUNW. In conclusion, MHO and MUNW are not benign conditions and pose a higher risk for incident CKD. Obesity, whether in the presence or absence of metabolic health, is a risk factor for CKD.
A series of novel triphenylamine/carbazole‐based D–D–π–π–A dyes DH1–4 and a mesoporous anatase cubic “microcage” TiO2 material (denoted as MC‐TiO2) were synthesized and combined to obtain ...dye‐sensitized photocatalysts (denoted as DHn/Pt/MC‐TiO2, n=1–4). These catalysts showed better performances in visible‐light‐driven H2 evolution from water than DHn/Pt/P25‐TiO2 catalysts based on commercial P25‐TiO2 bulk semiconductor under similar conditions. Compared with P25‐TiO2 particles, the porous MC‐TiO2 had a large Brunauer–Emmett–Teller surface area, porosity, and exposed {0 0 1} crystal plane, which greatly contributed to the photocatalytic activity. The optimized DH2/Pt/MC‐TiO2 photocatalyst exhibited an attractive H2 production rate (16.28 mmol g−1 h−1 based on catalyst mass), and the optimized DH4/Pt/MC‐TiO2 photocatalyst showed good stability turnover number (TON) of 16 699 in 105 h based on dye number, which represents one of the best performances among all reported visible‐light‐driven heterogeneous catalytic systems. Compared with the other dyes in this series, the high H2 production rate of DH2 on Pt/MC‐TiO2 can be attributed to its size‐matching effect and thus high dye loading amount, whereas the high TON and durability of DH4/Pt/MC‐TiO2 are probably related to the rapid regeneration kinetics of DH4.
Coming out of their cage: A series of highly robust hybrid catalysts DHn/Pt/MC‐TiO2 (n=1–4) based on D–D–π–π–A metal‐free dyes DH1–4 and an anatase cubic mesoporous microcage TiO2 are prepared. The catalysts display efficient and persistent photocatalytic water splitting activities (turnover number=16 600 in 105 h for DH4/Pt/MC‐TiO2).
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