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Assisted reproduction technology (ART) procedures are often impacted by post-ovulatory aging (POA), which can lead to reduced fertilization rates and impaired embryo development. This study used RNA sequencing analysis and experimental validation to study the similarities and differences between in vivo- and vitro-matured porcine oocytes before and after POA. Differentially expressed genes (DEGs) between fresh in vivo-matured oocyte (F_vivo) and aged in vivo-matured oocyte (A_vivo) and DEGs between fresh in vitro-matured oocyte (F_vitro) and aged in vitro-matured oocyte (A_vitro) were intersected to explore the co-effects of POA. It was found that "organelles", especially "mitochondria", were significantly enriched Gene Ontology (GO) terms. The expression of genes related to the "electron transport chain" and "cell redox homeostasis" pathways related to mitochondrial function significantly showed low expression patterns in both A_vivo and A_vitro groups. Weighted correlation network analysis was carried out to explore gene expression modules specific to A_vivo. Trait–module association analysis showed that the red modules were most associated with in vivo aging. There are 959 genes in the red module, mainly enriched in "RNA binding", "mRNA metabolic process", etc., as well as in GO terms, and "spliceosome" and "nucleotide excision repair" pathways. DNAJC7, IK, and DDX18 were at the hub of the gene regulatory network. Subsequently, the functions of DDX18 and DNAJC7 were verified by knocking down their expression at the germinal vesicle (GV) and Metaphase II (MII) stages, respectively. Knockdown at the GV stage caused cell cycle disorders and increase the rate of abnormal spindle. Knockdown at the MII stage resulted in the inefficiency of the antioxidant melatonin, increasing the level of intracellular oxidative stress, and in mitochondrial dysfunction. In summary, POA affects the organelle function of oocytes. A_vivo oocytes have some unique gene expression patterns. These genes may be potential anti-aging targets. This study provides a better understanding of the detailed mechanism of POA and potential strategies for improving the success rates of assisted reproductive technologies in pigs and other mammalian species. [ABSTRACT FROM AUTHOR]

BACKGROUND Red bed sandstone is a set of continental or shallow lake clastic rocks in the Danxia landform. Accurate determination of Fe(Ⅱ) and Fe(Ⅲ) in red bed sandstone that indicates the redox relationship during weathering can serve as the dividing basis of weathering degree and depth of the block. During the determination of iron content by phenanthroline spectrophotometry, Fe(Ⅱ) is easily oxidized and the result is a lower value than it should be. Effective prevention of oxidation is the focus of accurate measurement of Fe(Ⅱ) and Fe(Ⅲ) content. OBJECTIVES To explore the preservation method of Fe(Ⅱ) during dissolution and establish a spectrophotometric method for the determination of Fe(Ⅱ) and total iron in red sandstone. METHODS Color reagents were added in the samples, and the samples were dissolved by hydrofluoric acid and dilute sulfuric acid, in a constant temperature water bath at 90℃. Hydroxylamine hydrochloride was used as a reducing agent, o-phenanthroline was used as a chromogenic agent, pH was adjusted by acetate-ammonium acetate buffer, and trace Fe(Ⅱ) and total iron were determined by spectrophotometer. RESULTS The detection limit of Fe(Ⅱ) was 0.002%, relative standard deviation (RSD, n=8) was less than 2%, and the standard recovery was between 92.6% and 94.7%. The Fe(Ⅱ) content of red sandstone in the Danxia landform area of Chishui was determined by this analysis method. The content of Fe(Ⅱ) ranged from 0.01% to 0.1%, the total iron content was 0.7%-1.5%, and the content of Fe(Ⅲ) calculated by subtraction was 0.7%-1.5%. The measurement results were consistent with those of X-ray fluorescence spectrometry and potassium complexate titration method. CONCLUSIONS This method uses developer and hydrofluoric acid-dilute sulfuric acid to dissolve the samples, which can effectively preserve the original Fe(Ⅱ) in sandstone. The same solution can be used for the determination of both total iron and Fe(Ⅱ) which provides a simple and accurate analysis method for various types of iron content in red bed sandstone.

Highly active oxygen evolution reaction (OER) electrocatalysts, such as those containing Fe, often face the challenge of severe dissolution of active elements. Addressing this concern through the establishment of a dynamically stable interface during OER presents a promising strategy, achieved by manipulation of catalyst components. Herein, the findings reveal that Fe loss during OER predominantly occurs during the initial activation phase, marked by irreversible structural distortion that disrupts interfacial dynamical stability. By investigating the structural evolution of Fe‐containing Prussian blue analogs, serving as a model OER precatalyst, the correlation between precatalyst structural changes and interfacial dynamic stability is elucidated. Utilizing thermal annealing of CoFe bimetal Prussian blue, favorable thermodynamic conditions are induced for generating cyano vacancies within the matrix, thereby facilitating enhanced initial activation during OER. Consequently, catalytically active and stable oxyhydroxide species rapidly form at the interface, exhibiting robust interactions with interfacial Fe elements to stabilize interface dynamics. Suppression of the irreversible structural distortion responsible for active element loss during initial activation culminates in enhanced OER activity and stability. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are among the most appealing porous materials with a wide range of surface chemistry, high pore structure, high specific surface area and various functionalities. They have found extensive use in a variety of industries. The handling and processing of their properties, however, continue to be quite difficult, which limits the use of MOFs. The most plentiful and environmentally friendly biopolymer in the world is cellulose, and by combining cellulose with MOFs, it is possible to create engineered materials with a variety of hitherto unachievable qualities. This is an excellent way to increase the usage of MOFs in functional materials. This review describes the synthesis of cellulose MOFs composites, mainly MOFs and cellulose compounded in aqueous solution, with two synthetic strategies: in-situ and ex-situ synthesis. By completing further post-processing procedures, the aqueous mixture of MOFs and cellulose can be further processed into four different types of composites, including powders, films, aerogels and hydrogels. We also highlight the use of MOF cellulose composites for antibacterial and drug delivery in nanomedicine. The primary present restrictions on MOF cellulose composites are also reviewed, as well as possible future research directions. [ABSTRACT FROM AUTHOR]

Zinc finger and SCAN domain-containing 4 (ZSCAN4), a DNA-binding protein, maintains telomere length and plays a key role in critical aspects of mouse embryonic stem cells, including maintaining genomic stability and defying cellular senescence. However, the effect of ZSCAN4 in porcine parthenogenetic embryos remains unclear. To investigate the function of ZSCAN4 and the underlying mechanism in porcine embryo development, ZSCAN4 was knocked down via dsRNA injection in the one-cell stage. ZSCAN4 was highly expressed in the four- and five- to eight-cell stages in porcine embryos. The percentage of four-cell stage embryos, five- to eight-cell stage embryos, and blastocysts was lower in the ZSCAN4 knockdown group than in the control group. Notably, depletion of ZSCAN4 induced the protein expression of DNMT1 and 5-Methylcytosine (5mC, a methylated form of the DNA base cytosine) in the four-cell stage. The H3K27ac level and ZGA genes expression decreased following ZSCAN4 knockdown. Furthermore, ZSCAN4 knockdown led to DNA damage and shortened telomere compared with the control. Additionally, DNMT1-dsRNA was injected to reduce DNA hypermethylation in ZSCAN4 knockdown embryos. DNMT1 knockdown rescued telomere shortening and developmental defects caused by ZSCAN4 knockdown. In conclusion, ZSCAN4 is involved in the regulation of transcriptional activity and is essential for maintaining telomere length by regulating DNMT1 expression in porcine ZGA. [ABSTRACT FROM AUTHOR]

Y‐box binding protein 1 (YBX1) is a member of the family of DNA‐ and RNA‐binding proteins that play crucial roles in multiple aspects, including RNA stabilization, translational repression, and transcriptional regulation; however, its roles in embryo development remain less known. In this study, to investigate the function of YBX1 and its mechanism of action in porcine embryo development, YBX1 was knocked down by microinjecting YBX1 siRNA at the one‐cell stage. YBX1 is located in the cytoplasm during embryonic development. The mRNA level of YBX1 was increased from the four‐cell stage to the blastocyst stage but was significantly decreased in YBX1 knockdown embryos compared with the control. Moreover, the percentage of blastocysts was decreased following YBX1 knockdown compared with the control. Defecting YBX1 expression increased maternal gene mRNA expression and decreased zygotic genome activation (ZGA) gene mRNA expression and histone modification owing to decreased levels of N6‐methyladenosine (m6A) writer N6‐adenosine‐methyltransferase 70 kDa subunit (METTL3) and reader insulin‐like growth factor 2 mRNA‐binding protein (IGF2BP1). In addition, IGF2BP1 knockdown showed that YBX1 regulated the ZGA process through m6A modification. In conclusion, YBX1 is essential for early embryo development because it regulates the ZGA process. [ABSTRACT FROM AUTHOR]

Background: Activating transcription factor 7 (ATF7) is a member of the ATF/cAMP response element (CRE) B superfamily. ATF2, ATF7, and CRE‐BPa are present in vertebrates. Drosophila and fission yeast have only one homologue: dATF2 and Atf1, respectively. Under normal conditions, ATF7 promotes heterochromatin formation by recruiting histone H3K9 di‐ and tri‐methyltransferases. Once the situation changes, all members are phosphorylated by the stress‐activated kinase P38 in response to various stressors. However, the role of ATF7 in early porcine embryonic development remains unclear. Results: In this study, we found that ATF7 gradually accumulated in the nucleus and then localized on the pericentric heterochromatin after the late 4‐cell stage, while being co‐localized with heterochromatin protein 1 (HP1). Knockdown of ATF7 resulted in decreases in the blastocyst rate and blastocyst cell number. ATF7 depletion resulted in downregulation of HP1 and histone 3 lysine 9 dimethylation (H3K9me2) expression. These effects were alleviated when P38 activity was inhibited. High temperatures increased the expression level of pP38, while reducing the quality of porcine embryos, and led to ATF7 phosphorylation. The expression level of H3K9me2 and HP1 was decreased and regulated by P38 activity. Conclusion: Stress‐induced ATF7‐dependent epigenetic changes play important roles in early porcine embryonic development. [ABSTRACT FROM AUTHOR]

Alkaline electrochemical water oxidation powered by renewable energies is a promising and environmentally friendly way to produce hydrogen. The industrial water electrolyzers are commonly operated at a high current density, calling for abundant and durable active sites to participate in. The rational design of hierarchically structured electrocatalysts is thus essential to industrial water electrolyzers. Herein, we develop a Fe3+ induced nanosizing strategy for fabricating such a hierarchical FeCo LDH@Co3O4 (LDH: layered double hydroxide) nanostructure array for high-rate water oxidation. Density functional theory (DFT) simulations indicate that the introduction of Fe3+ with a small ion radius and high electrical repulsion in the LDH layer distorted the LDH layer, resulting in a reduced nanosheet size and enabling the formation of a hierarchical structure. Such structure cannot be achieved without the participation of Fe3+ cations. Benefiting from the significantly enhanced electrochemical surface areas and charge/mass transport due to the hierarchical structure together with the boosted intrinsic activity by electronic modulation of Fe3+, such FeCo LDH@Co3O4 electrode can deliver an industrial-level current density of 1,000 mA·cm−2 at a small overpotential of 392 mV for water oxidation. When assembled in a water electrolyzer, it delivers a current density of 100 mA·cm−2 at a low operation voltage of 1.61 V. Powered by solar light, the electrolyzer demonstrates high solar-to-hydrogen efficiency of 18.15% with stable and reproducible photoresponse. These results provide new insights for constructing hierarchical nanostructures for advanced water oxidation and other diverse applications. [ABSTRACT FROM AUTHOR]

Rotenone is a commonly used insecticidal chemical in agriculture and it is an inhibitor of mitochondrial complex Ⅰ. Previous studies have found that rotenone induces the production of reactive oxygen species (ROS) by inhibiting electron transport in the mitochondria of somatic and germ cells. However, there is little precise information on the effects of rotenone exposure in porcine oocytes during in vitro maturation, and the mechanisms underlying these effects have not been determined. The Cumulus-oocyte complexes were supplemented with different concentrations of rotenone to elucidate the effects of rotenone exposure on the meiotic maturation of porcine oocytes during in vitro maturation for about 48 hours. First, we found that the maturation rate and expansion of cumulus cells were significantly reduced in the 3 and 5 μM rotenone-treated groups. Subsequently, the concentration of rotenone was determined to be 3 μM. Also, immunofluorescence, western blotting, and image quantification analyses were performed to test the rotenone exposure on the meiotic maturation, total and mitochondrial ROS, mitochondrial function and biogenesis, mitophagy and apoptosis in porcine oocytes. Further experiments showed that rotenone treatment induced mitochondrial dysfunction and failure of mitochondrial biogenesis by repressing the level of SIRT1 during in vitro maturation of porcine oocytes. In addition, rotenone treatment reduced the ratio of active mitochondria to total mitochondria, increased ROS production, and decreased ATP production. The levels of LC3 and active-caspase 3 were significantly increased by rotenone treatment, indicating that mitochondrial dysfunction induced by rotenone increased mitophagy but eventually led to apoptosis. Collectively, these results suggest that rotenone interferes with porcine oocyte maturation by inhibiting mitochondrial function. [ABSTRACT FROM AUTHOR]

The recent emergence of electrically conductive nanoporous membranes based on graphene and other 2D materials opens up new opportunities to revisit some longstanding nanoconfined ion transport problems under electrification. This work probes the ionic resistance in electrified multilayered graphene membranes with electrochemical impedance spectroscopy. This study demonstrates that the combination of additive‐free feature and tunable slit pore sizes in the sub‐10 nm range in graphene‐based membranes has made it possible to deconvolute the different ionic processes from the impedance obtained and examine the exclusive influence of pore size on the ionic resistance in a quantitative manner. The trends revealed for the ionic resistance at the pore entrance and inside the pores under severe nanoconfinement (<2 nm) are found to be generally consistent with the microscale theoretical simulations previously reported. It also allows a quantitative analysis of the relative effects of the external polarization potential and ion identity under nanoconfinement. The results suggest that the classic electrochemical impedance spectroscopy technique, when applied to appropriate nanoporous electrode materials, can provide rich information about nanoconfined ion transport phenomena under electrification for fundamental understanding and application development. [ABSTRACT FROM AUTHOR]

Population growth and industrial development have exacerbated environmental pollution of both land and aquatic environments with toxic and harmful materials. Luminescence-based chemical sensors crafted for specific hazardous substances operate on host-guest interactions, leading to the detection of target molecules down to the nanomolar range. Particularly, the luminescence-based sensors constructed on the basis of metal-organic frameworks (MOFs) are of increasing interest, as they can not only compensate for the shortcomings of traditional detection techniques, but also can provide more sensitive detection for analytes. Recent years have seen MOFs-based fluorescent sensors show outstanding advantages in the field of hazardous substance identification and detection. Here, we critically discuss the application of MOFs for the detection of a broad scope of hazardous substances, including hazardous gases, heavy metal ions, radioactive ions, antibiotics, pesticides, nitro-explosives, and some harmful solvents as well as luminous and sensing mechanisms of MOF-based fluorescent sensors. The outlook and several crucial issues of this area are also discussed, with the expectation that it may help arouse widespread attention on exploring fluorescent MOFs (LMOFs) in potential sensing applications. [ABSTRACT FROM AUTHOR]

Citrinin (CTN) is a polyketide mycotoxin produced by several strains of Penicillium , Monascus , and Aspergillus. While CTN poses various toxic effects on the female reproductive system in animals, its direct effects on germ cell development are unclear. This study aimed to evaluate the effects of increasing concentrations of CTN (0,20,40,80,100 μM) on porcine oocyte in vitro maturation. Our results indicate that CTN supplementation inhibited polar body extrusion in a dose-dependent manner. Actin and spindle assembly were also disrupted after treatment, indicating that CTN affects the cytoskeleton of porcine oocytes. Oxidative stress and apoptosis were observed under CTN treatment to explore the cause of meiotic maturation failure in porcine oocytes. The results showed that reactive oxygen species levels, cathepsin B activity, and caspase-3 activity were increased in the treated group, indicating that CTN induced oxidative stress and apoptosis. In conclusion, CTN exposure could reduce porcine oocyte maturation by affecting cytoskeletal dynamics, oxidative stress, and apoptosis. • CTN exposure inhibited porcine oocyte maturation. • CTN exposure disrupted the cytoskeleton of porcine oocyte. • CTN exposure induced oxidative stress in porcine oocyte. • CTN exposure caused apoptosis in porcine oocytes. [ABSTRACT FROM AUTHOR]

Although the significance of charge diffusion has been recognized in many high-performance energy devices, it has received very less attention in the design of electrocatalysts for the oxygen evolution reaction (OER), which is particularly crucial for highly active but less conductive OER electrocatalysts, such as two-dimensional metal hydroxides (MHs) with anisotropic conductivity. Herein, we report the elaborate design of a series of CoFe hydroxide nanosheets on graphene (CFH@G) composites to demonstrate the importance of charge diffusion regulation in improving the OER activity of MHs. It was discovered that the few-layer-thick CFH nanosheets lying on the graphene substrate provided an effective in-plane charge diffusion pathway, while keeping the substrate surface entirely covered by the laid nanosheets is necessary for providing sufficient active sites. The overly thick or stacked nanosheets are not favourable for charge diffusion, especially at large current outputs. By regulating the charge diffusion properties, the best-performing CFH@G-based material can deliver a steady OER current density of 2000 mA cm−2 at a cost of only 1.507 V under near-industrial conditions (6 M KOH and 60 °C). A practical water electrolyzer also demonstrated an impressive current output of 400 mA cm−2 at 1.694 V as well as a steady solar-to-hydrogen efficiency of 17.41%. These findings provide new insights into the role of charge diffusion in water oxidation and may open up an avenue for developing low-cost, stable and efficient electrocatalysts for practical water electrolysis and diverse energy devices. [ABSTRACT FROM AUTHOR]

Fe-doped Co3O4 polycrystalline nanosheets vertically grown on carbon cloth were developed as self-standing efficient bifunctional electrocatalysts for oxygen reduction and evolution, enabling high-performance Zn–air batteries with a power density of 268.6 mW cm−2 and superior cycling stability. [ABSTRACT FROM AUTHOR]

Background: Despite the fact that thyroid surgery has evolved towards minimal incisions and endoscopic approaches, the role of total endoscopic thyroidectomy (TET) in thyroid cancer has been highly disputed. We performed a systematic review and meta-analyses of peer reviewed studies in order to evaluate the safety and effectiveness of TET compared with conventional open thyroidectomy (COT) in papillary thyroid cancer (PTC).Method: Medical literature databases such as PubMed, Embase, the Cochrane Library, and Web of science were systematically searched for articles that compared TET and COT in PTC treatment from database inception until March 2019. The quality of the studies included in the review was evaluated using the Downs and Black scale using Review Manager software Stata V.13.0 for the meta-analysis.Results: The systematic review and meta-analysis were based on 5664 cases selected from twenty publications. Criteria used to determine surgical completeness included postoperative thyroglobulin (TG) levels, recurrence of the tumor after long-term follow-up. Adverse event and complication rate scores included transient recurrent laryngeal nerve (RLN) palsy, permanent RLN palsy, transient hypocalcaemia, permanent hypocalcaemia, operative time, number of removed lymph nodes, length of hospital stay and patient cosmetic satisfaction. TET was found to be generally equivalent to COT in terms of surgical completeness and adverse event rate, although TET resulted in lower levels of transient hypocalcemia (OR 1.66; p < 0.05), a smaller number of the retrieved lymph nodes (WMD 0.46; p < 0.05), and better cosmetic satisfaction (WMD 1.73; p < 0.05). COT was associated with a shorter operation time (WMD - 50.28; p < 0.05) and lower rates of transient RLN palsy (OR 0.41; p < 0.05).Conclusions: The results show that in terms of safety and efficacy, TET was similar to COT for the treatment of thyroid cancer. Indeed, the tumor recurrence rates and the level of surgical completeness in TET are similar to those obtained for COT. TET was associated with significantly lower levels of transient hypocalcemia and better cosmetic satisfaction, and thus is the better option for patients with cosmetic concerns. Overall, randomized clinical trials and studies with larger patient cohorts and long-term follow-up data are required to further demonstrate the value of the TET. [ABSTRACT FROM AUTHOR]

Cost-effective oxygen evolution reaction (OER) catalysts with both superb activity and stability are crucial for practical electrocatalytic water splitting. We herein come up with a metal carbonate hydroxide and metal sulfide (MS/MCH) heterostructure via in situ generating MS on MCH to tackle the conflict between activity and durability. The heterostructure in a unique "nanoparticle-in-nanosheet" configuration features abundant hetero-interfaces between MS and MCH, allowing for effective electron transfer from the antibonding orbital of M–S in MS to M–O in MCH and thus improving the stability of sulfides during water oxidation. Simultaneously, such coupling is able to modulate the electronic structure of the metal centre, thus enhancing the intrinsic activity. The coupled heterostructure therefore exhibits steady OER performance with an ultrasmall overpotential of 226 to deliver a current of 10 mA cm−2 and can output an industrial-level current of 1000 mA cm−2 at an overpotential of only 367 mV. Furthermore, the overall water electrolyzer with such a heterostructure as an anode presents stable hydrogen production at 100 mA cm−2 with a small cell voltage of 1.62 V and a high solar to hydrogen efficiency of 16.99%. Such superior catalytic performance demonstrates the feasibility of introducing a heterostructure to tailor the local electrocatalytic properties and opens up an avenue toward designing efficient OER catalysts for clean hydrogen production and diverse energy conversion devices. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2) to value-added chemicals and fuels has attracted great interest, although it suffers from low energy efficiency and selectivity. Herein, we discover that the pore structure of a supported catalyst significantly affects the products and efficiency of the electrochemical CO2 reduction reaction (CO2RR). Three-dimensional (3D) porous carbon (PC) sheets with abundant micropores and macropores and mesopore-dominant activated carbon (AC) have been used to construct electrocatalysts with uniformly dispersed SnO2 nanoparticles. SnO2/PC exhibits efficient formate production from the electrochemical CO2RR with a high faradaic efficiency of 92% and partial current density of 29 mA cm−2 at −0.86 V, ranking as a top-tier Sn-based catalyst. Importantly, systematic investigation and comparison with SnO2/AC show that the space-confinement effect of micropores enhances CO2RR selectivity towards formate by inhibiting proton transfer to active sites and thus suppressing the HER process, while the 3D sheet structure with abundant macropores provides mass and charge transport highways, making more active sites accessible for an effective CO2RR and thus a larger current density. These findings shed light on the design of efficient electrocatalysts via engineering pore structures for diverse applications. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this meta-analysis was to compare high inferior mesenteric artery (IMA) ligation (HL) with low IMA ligation (LL) for the treatment of colorectal cancer and to evaluate the lymph node yield, survival benefit, and safety of these surgeries. Methods: PubMed, Embase, Cochrane Library, Web of Science, and China Biomedical Literature Database (CBM) were systematically searched for relevant articles that compared HL and LL for sigmoid or rectal cancer. We calculated the odds ratio (OR) with 95% confidence intervals (CIs) for dichotomous outcomes and the weighted mean difference (WMD) for continuous outcomes. Results: In total, 30 studies were included in this analysis. There were significantly higher odds of anastomotic leakage and urethral dysfunction in patients treated with HL compared to those treated with LL (OR = 1.29; 95% CI = 1.08 to 1.55; OR = 2.45; 95% CI = 1.39 to 4.33, respectively). There were no significant differences between the groups in terms of the total number of harvested lymph nodes, the number of harvested lymph nodes around root of the IMA, local recurrence rate, and operation time. Further, no statistically significant group differences in 5-year overall survival rates and 5-year disease-free survival rates were detected among all patients nor among subgroups of stage II patients and stage III patients, respectively. Conclusions: LL can achieve equivalent lymph node yield to HL, and both procedures have similar survival benefits. However, LL is associated with a lower incidence of leakage and urethral dysfunction. Thus, LL is recommended for colorectal cancer surgery. [ABSTRACT FROM AUTHOR]

Combining ultrasmall NiS2 nanodots with three-dimensional carnation-like CoS2 microstructures is demonstrated to be able to enhance the electrocatalytic activities for both the oxygen and hydrogen evolution reactions, leading to efficient overall alkaline water splitting. [ABSTRACT FROM AUTHOR]

High activity and stability are two requisites for a high-performance electrocatalyst but usually have to be balanced. CoS2 is regarded as an alternative electrocatalyst for the hydrogen evolution reaction (HER) but its HER activity and durability still cannot meet the criteria for practical applications. Here, we develop a strategy to simultaneously boost the HER activity and durability of CoS2 by fabricating polycrystalline nanowire (PCNW) arrays with dual doping of Fe and P. Systematic investigations demonstrate that Fe incorporation increases the active sites, while P substitution significantly boosts chemical and mechanical stability as well as HER kinetics. PCNW arrays provide abundant accessible active sites and allow for prompt gas release. As a result, Fe/P-CoS2 PCNW exhibits excellent HER performance with a low overpotential of 80 mV at 10 mA cm−2 and robust durability in acidic media. Such a strategy may provide opportunities for designing efficient and durable HER electrodes for practical water splitting. [ABSTRACT FROM AUTHOR]

Developing efficient counter electrodes (CEs) and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells (QDSSCs). Here, we report a facile strategy to prepare self-supported and robust CoS2 and NiS nanocrystals-assembled nanosheets directly grown on carbon paper (MSx NS@CP) as efficient counter electrodes for QDSSCs. Such CEs integrate the merits of fast electron transfer from interconnected conductive scaffold, efficient mass transfer from hierarchically vertical nanosheet on 3D open substrate, as well as abundant highly active catalytic sites from metal sulphide nanocrystal units. As a result, QDDSCs based on such CoS2 NS@CP and NiS NS@CP CEs achieve a PCE of 8.88% and 7.53%, respectively. The detailed analyses suggest that CoS2 NS@CP has the highest catalytic activity and shows the lowest charger transfer resistance, leading to the highest PCE. These findings may inspire the design and exploration of other self-supported efficient CEs by integrating highly active catalysts onto 3D conductive networks for efficient QDSSCs. [ABSTRACT FROM AUTHOR]

A facile and scalable solid-state synthesis strategy is developed to produce hierarchical coralline-like nanostructured electrocatalysts with cobalt nanoparticles and Co–NX sites for efficient oxygen reduction reaction, opening up an avenue for the mass production of non-precious metal catalysts for metal–air batteries and fuel cells, etc. [ABSTRACT FROM AUTHOR]