Predictive value of a stemness-based classifier for prognosis and immunotherapy response of hepatocellular carcinoma based on bioinformatics and machine-learning strategies.

Objective: Significant advancements have been made in hepatocellular carcinoma (HCC) therapeutics, such as immunotherapy for treating patients with HCC. However, there is a lack of reliable biomarkers for predicting the response of patients to therapy, which continues to be challenging. Cancer stem cells (CSCs) are involved in the oncogenesis, drug resistance, and invasion, as well as metastasis of HCC cells. Therefore, in this study, we aimed to create an mRNA expression-based stemness index (mRNAsi) model to predict the response of patients with HCC to immunotherapy. Methods: We retrieved gene expression and clinical data of patients with HCC from the GSE14520 dataset and the Cancer Genome Atlas (TCGA) database. Next, we used the "one-class logistic regression (OCLR)" algorithm to obtain the mRNAsi of patients with HCC. We performed "unsupervised consensus clustering" to classify patients with HCC based on the mRNAsi scores and stemness subtypes. The relationships between the mRNAsi model, clinicopathological features, and genetic profiles of patients were compared using various bioinformatic methods. We screened for differentially expressed genes to establish a stemness-based classifier for predicting the patient's prognosis. Next, we determined the effect of risk scores on the tumor immune microenvironment (TIME) and the response of patients to immune checkpoint blockade (ICB). Finally, we used qRT-PCR to investigate gene expression in patients with HCC. Results: We screened CSC-related genes using various bioinformatics tools in patients from the TCGA-LIHC cohort. We constructed a stemness classifier based on a nine-gene (PPARGC1A, FTCD, CFHR3, MAGEA6, CXCL8, CABYR, EPO, HMMR, and UCK2) signature for predicting the patient's prognosis and response to ICBs. Further, the model was validated in an independent GSE14520 dataset and performed well. Our model could predict the status of TIME, immunogenomic expressions, congenic pathway, and response to chemotherapy drugs. Furthermore, a significant increase in the proportion of infiltrating macrophages, Treg cells, and immune checkpoints was observed in patients in the high-risk group. In addition, tumor cells in patients with high mRNAsi scores could escape immune surveillance. Finally, we observed that the constructed model had a good expression in the clinical samples. The HCC tumor size and UCK2 genes expression were significantly alleviated and decreased, respectively, by treatments of anti-PD1 antibody. We also found knockdown UCK2 changed expressions of immune genes in HCC cell lines. Conclusion: The novel stemness-related model could predict the prognosis of patients and aid in creating personalized immuno- and targeted therapy for patients in HCC.

Zeolitic imidazolate framework derived Fe catalyst electrocatalytic-driven atomic hydrogen for efficient reduction of nitrate to N2.

Excessive discharge of nitrogen-containing chemical products into the natural water environment leads to the serious environmental problem of nitrate-nitrogen pollution, threatening the ecological balance and human health. In this study, we propose an efficient denitrification electrochemical method utilizing iron-doped zeolite imidazolium framework derived defective nitrogen-doped carbon (d-FeNC) catalysts. The d-FeNC catalyst exhibited 97 % nitrate removal efficiency and 94 % total nitrogen (TN) removal, and the reaction rate constant was increased from 0.73 h-1 of the Fe-undoped electrocatalyst (d-NC) to 1.11 h-1. The successful synthesis of d-FeNC with carbon defect sites and encapsulated Fe was confirmed by in-depth characterization. In situ electron paramagnetic resonance (EPR) analysis in conjunction with cyclic voltammetry (CV) tests confirmed the carbon substrates with defect enhanced the trapping of atomic hydrogen (H*) on the catalyst surface. Density functional theory (DFT) calculations clarified the doping of Fe facilitated the adsorption of nitrate, resulting in contact of H* with nitrate on the catalyst surface. In the synergy of the defective state organic framework and metal Fe, H* and nitrate realized a collision process. The electrochemical denitrification system achieved an excellent nitrate removal capacity of 7587 mgN·g-1cat in high-concentration nitrate solution and showed excellent stability under various conditions. Overall, this study underscores the potential of defective iron-doped carbon catalysts for efficient electrocatalytic denitrification, providing a promising approach for sustainable wastewater treatment.

Phosphate Adsorption on Cerium/Terephthalic Acid Metal-Organic Frameworks (Ce-MOF) Driven by Effective Electrostatic Attraction and Ligand Exchange in a Wide pH Range.

Eutrophication has posed a threat to aquatic ecosystems, so it's urgent to remove excessive phosphate from water. In this study, we developed an adsorbent material, cerium/terephthalic-acid metal-organic-frameworks (Ce-MOF), to remove phosphate from different water systems. The optimal Ce-MOF presented a maximum phosphate adsorption capacity of 377.2 mg/g, approximately 3.7 times higher than that of the commercial phosphate adsorbent (Phoslock: 101.6 mg/g). Experimental and computational analysis suggested that pH dominated the adsorption process. The main forces driving the adsorption process changed from the synergistic effect of electrostatic attraction and ligand exchange at lower pH to only ligand exchange at the increased pH values. Hence, the Ce-MOF is applicable for phosphate adsorption in a wide pH range. Impressively, the adsorbent remained an excellent phosphate adsorption performance in the real water containing various interfering ions and organic matters, indicating the potential of Ce-MOF for the practical use to solve the water eutrophication issue.

High-Energy and Stable Subfreezing Aqueous Zn-MnO2 Batteries with Selective and Pseudocapacitive Zn-Ion Insertion in MnO2.

One major challenge of aqueous Zn-MnO2 batteries for practical applications is their unacceptable performance below freezing temperatures. Here the use of simple Zn(ClO4 )2 aqueous electrolytes is described for all-weather Zn-MnO2 batteries even down to -60 °C. The symmetric, bulky ClO4 - anion effectively disrupts hydrogen bonds between water molecules and provides intrinsic ion diffusion even while frozen, and enables ≈260 mAh g-1 on MnO2 cathodes at -30 °C . It is identified that subfreezing cycling shifts the reaction mechanism on the MnO2 cathode from unstable H+ insertion to predominantly pseudocapacitive Zn2+ insertion, which converts MnO2 nanofibers into complicated zincated MnOx that are largely disordered and appeared as crumpled paper sheets. The Zn2+ insertion at -30 °C is faster and much more stable than at 20 °C, and delivers ≈80% capacity retention for 1000 cycles without Mn2+ additives. In addition, simple Zn(ClO4 )2 electrolyte also enables a nearly fully reversible and dendrite-free Zn anode at -30 °C with ≈98% Coulombic efficiency. Zn-MnO2 prototypes with an experimentally verified unit energy density of 148 Wh kg-1 at a negative-to-positive ratio of 1.5 and an electrolyte-to-capacity ratio of 2.0 are further demonstrated.

Detection of Parental Contribution to Molar Genome Leads to Diagnosis of Recurrent Hydatidiform Mole in a Family with NLRP7 Variants.

Introduction: Genetically, complete hydatidiform mole (CHM) is androgenetic diploid, containing two sets of paternal chromosomes. In most cases, recurrent HM (RHM) is CHM but has diploid biparental chromosome constitution. Case report: We report a mother with RHM, both with biparental diploidy. The mother was compound heterozygous for two variants, c.1720dup, p.(C574Lfs*4) and c.2165A > G, p.(D722G) of the NLRP7 gene, as was a brother who fathered 2 normal pregnancies. Conclusion: The genotype study should be obtained for patients of CHM, even in their first pregnancy, followed by genetic screening for maternal-effect variants in those with biparental moles. This strategy will identify patients in their first pregnancy with HM that have a decreased chance for a normal pregnancy, to allow genetic counseling, perhaps utilizing a donor egg.

Scalable Synthesis of Pt/SrTiO3 Hydrogenolysis Catalysts in Pursuit of Manufacturing-Relevant Waste Plastic Solutions.

An improved hydrothermal synthesis of shape-controlled, size-controlled 60 nm SrTiO3 nanocuboid (STO NC) supports, which facilitates the scalable creation of platinum nanoparticle catalysts supported on STO (Pt/STO) for the chemical conversion of waste polyolefins, is reported herein. This synthetic method (1) establishes that STO nucleation prior to the hydrothermal treatment favors nanocuboid formation, (2) produces STO NC supports with average sizes ranging from 25 to 80 nm with narrow size distributions, and (3) demonstrates how SrCO3 formation and variation in solution pH prevent the formation of STO NCs. The STO synthesis was scaled-up and conducted in a 4 L batch reactor, resulting in STO NCs of comparable size and morphology (m = 22.5 g, davg = 58.6 ± 16.2 nm) to those synthesized under standard hydrothermal conditions in a lab-scale 125 mL autoclave reactor. Size-controlled STO NCs, ranging in roughly 10 nm increments from 25 to 80 nm, were used to support Pt deposited through strong electrostatic adsorption (SEA), a practical and scalable solution-based method. Using SEA techniques and an STO support with an average size of 39.3 ± 6.3 nm, a Pt/STO catalyst with 3.6 wt % Pt was produced and used for high-density polyethylene hydrogenolysis under previously reported conditions (170 psi H2, 300 °C, 96 h; final product: Mw = 2400, D = 1.03). As a well-established model system for studying the behavior of heterogeneous catalysts and their supports, the Pt/STO system detailed in this work presents a unique opportunity to simultaneously convert waste plastic into commercially viable products while gaining insight into how scalable inorganic synthesis can support transformative manufacturing.

Prenatal diagnosis of a nonsense mutation in the L1CAM gene resulting in congenital hydrocephalus: A case report and literature review.

Congenital hydrocephalus is frequently caused by mutations in the L1 cell adhesion molecule (L1CAM) gene. The purpose of the present study was to identify possible causes of fetal hydrocephalus in a Chinese family. The samples from the parents and the hydrocephalic fetus were collected. Whole-exome sequencing and in-depth mutation analysis were performed. The identified variant, c.1267C>T.(p.Q423X), is situated on exon 11 of L1CAM gene (chromosome X:153134975). The fetus was confirmed to be hemizygous for the nonsense mutation and the mother was a heterozygous carrier. The mutation turns a glutamine into a premature stop codon at amino acid position 423. In conclusion, in the present study, a nonsense mutation in the L1CAM gene was identified during the prenatal diagnosis of a congenital hydrocephalic fetus from a Chinese family. The diagnosis highlighted the necessity of genetic screening for prenatal diagnosis.

Establishment of quantitative methodology for sophoridine analysis and determination of its pharmacokinetics and bioavailability in rat.

OBJECTIVE: The aim of this study is to develop a rapid and sensitive UPLC-MS/MS approach to determine the sophoridine (SOP) level in rat plasma and the pharmacokinetics of the substance. SIGNIFICANCE: Sophoridine is used as an anti-inflammatory, anti-virus, anti-microbial, and anti-tumor alkaloid. It is essential to explore specific detection methods for the quantitative analysis of SOP in the blood circulation. METHODS: The rat plasma samples were prepared by one-step protein precipitation with acetonitrile. Subsequently, the samples were separated by chromatography using a UPLC BEH C18 reversed-phase with an initial mobile phase of methanol and 0.1% formic acid aqueous solution. The gradient elution was performed at a fixed flow rate of 0.4 mL/min, and multiple reaction monitoring (MRM) mode with an electrospray positive ionization source was employed to detect the transitions of m/z 249.1 → 84.2 for SOP and m/z 264.3 → 69.8 for dendrobine (IS). The entire process required 3.5 min for each sample. RESULTS: A linear correlation was established over the range of 2-2000 ng/mL (r2≥0.9954) for SOP in rat plasma with a lower limit of quantification (LLOQ) at 2 ng/mL. The range of accuracy was tested between 94.90% and 100.80%, and the relative standard deviations (RSDs) toward both intra- and inter-day precision were <10%. Thus, this method was successfully applied to a pharmacokinetic study, and the subsequent results demonstrated a low absolute bioavailability of 2.32%. CONCLUSION: The present study established a reliable method that quantified the SOP concentration in rat plasma after administering a dose of 2 mg/kg intravenously or 20 mg/kg orally.

Corn Stalk-Derived Carbon Quantum Dots with Abundant Amino Groups as a Selective-Layer Modifier for Enhancing Chlorine Resistance of Membranes.

Low permeability and chlorine resistance of normal thin-film composite (TFC) membranes restrict their practical applications in many fields. This study reports the preparation of a high chlorine-resistant TFC membrane for forward osmosis (FO) by incorporating corn stalk-derived N-doped carbon quantum dots (N-CQDs) into the selective polyamide (PA) layer to construct a polydopamine (PDA) sub-layer (PTFCCQD). Membrane modification is characterized by surface morphology, hydrophilicity, Zeta potential, and roughness. Results show that TFCCQD (without PDA pretreatment) and PTFCCQD membranes possess greater negative surface charges and thinner layer-thickness (less than 68 nm). With N-CQDs and PDA pretreatment, the surface roughness of the PTFCCQD membrane decreases significantly with the co-existence of microsized balls and flocs with a dense porous structure. With the variation of concentration and type of draw solution, the PTFCCQD membrane exhibits an excellent permeability with low J(reverse salt flux)/J(water flux) values (0.1-0.25) due to the enhancement of surface hydrophilicity and the shortening of permeable paths. With 16,000 ppm·h chlorination, reverse salt flux of the PTFCCQD membrane (8.4 g m-2 h-1) is far lower than those of TFCCQD (136.2 g m-2 h-1), PTFC (127.6 g m-2 h-1), and TFC (132 g m-2 h-1) membranes in FO processes. The decline of salt rejection of the PTFCCQD membrane is only 8.2%, and the normalized salt rejection maintains 0.918 in the RO system (16,000 ppm·h chlorination). Super salt rejection is ascribed to the existence of abundant N-H bonds (N-CQDs), which are preferentially chlorinated by free chlorine to reduce the corrosion of the PA layer. The structure of the PA layer is stable during chlorination also due to the existence of various active groups grafted on the surface. This study may pave a new direction for the preparation of durable biomass-derivative (N-CQD)-modified membranes to satisfy much more possible applications.

Synergistics of Fe3C and Fe on Mesoporous Fe-N-C Sulfur Host for Nearly Complete and Fast Lithium Polysulfide Conversion.

The practical deployment of advanced Li-S batteries is severely constrained by the uncontrollable lithium polysulfide conversion under realistic conditions. Although a plethora of advanced sulfur hosts and electrocatalysts have been examined, the fundamental mechanisms are still elusive and predictive design approaches have not yet been established. Here, we examined a series of well-defined Fe-N-C sulfur hosts with systematically varied and strongly coupled Fe3C and Fe electrocatalysts, prepared by one-step pyrolysis of a novel Fex[Fe(CN)6]y/polypyrrole composite at different temperatures. We revealed the key roles of Fe3C and metallic Fe on modulating polysulfide conversion, in that the polar Fe3C strongly adsorbs polysulfide whereas the Fe particles catalyze fast polysulfide conversion. We then highlight the superior performance of the rational host with strongly coupled Fe3C and Fe on mesoporous Fe-N-C host on promoting nearly complete polysulfide conversion, especially for the challenging short-chain Li2S4 conversion to Li2S. The electrodeposited Li2S on this host was extremely reactive and can be readily charged back to S with minimal activation overpotential. Overall, Li-S batteries equipped with the novel sulfur host delivered a high specific capacity of 1350 mAh g-1 at 0.1C with a capacity retention of 96% after 200 cycles. This work provides new insights on the functional mechanism of advanced sulfur hosts, which could eventually translate into new design principles for practical Li-S batteries.

Mild α-Thalassemia Caused by a Mosaic α-Globin Gene Mutation.

We describe a new α-globin chain variant in a Chinese subject. This novel variant, with a Val→Met substitution at codon 93 of the α-globin chain, has been named Hb Qingcheng (HBA1: c.280G>A) for where the proband was born. A woman with somatic mosaicism for Hb Qingcheng presented with the phenotype of mild α-thalassemia (α-thal).

Healthy neonate born to a SARS-CoV-2 infected woman: A case report and review of literature.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly discovered coronavirus that has generated a worldwide outbreak of infections. Many people with coronavirus disease-2019 (COVID-19) have developed severe illness, and a significant number have died. However, little is known regarding infection by the novel virus in pregnant women. We herein present a case of COVID-19 confirmed in a woman delivering a neonate who was negative for SARS-CoV-2 and related it to a review of the literature on pregnant women and human coronavirus infections. CASE SUMMARY: The patient was a 36-year-old pregnant woman in her third trimester who had developed progressive clinical symptoms when she was confirmed as infected with SARS-CoV-2. Given the potential risks for both the pregnant woman and the fetus, an emergency cesarean section was performed, and the baby and his mother were separately quarantined and cared for. As a result, the baby currently shows no signs of SARS-CoV-2 infection (his lower respiratory tract samples were negative for the virus), while the mother completely recovered from COVID-19. CONCLUSION: Although we presented a single case, the successful result is of great significance for pregnant women with SARS-CoV-2 infection and with respect to fully understanding novel coronavirus pneumonia.

Cation Additive Enabled Rechargeable LiOH-Based Lithium-Oxygen Batteries.

Lithium-oxygen (Li-O2 ) batteries have attracted extensive research interest due to their high energy density. Other than Li2 O2 (a typical discharge product in Li-O2 batteries), LiOH has proved to be electrochemically active as an alternative product. Here we report a simple strategy to achieve a reversible LiOH-based Li-O2 battery by using a cation additive, sodium ions, to the lithium electrolyte. Without redox mediators in the cell, LiOH is detected as the sole discharge product and it charges at a low charge potential of 3.4 V. A solution-based reaction route is proposed, showing that the competing solvation environment of the catalyst and Li+ leads to LiOH precipitation at the cathode. It is critical to tune the cell chemistry of Li-O2 batteries by designing a simple system to promote LiOH formation/decomposition.

Microfluidic, One-Batch Synthesis of Pd Nanocrystals on N-Doped Carbon in Surfactant-Free Deep Eutectic Solvents for Formic Acid Electrochemical Oxidation.

One of the grand challenges that impedes practical applications of nanomaterials is the lack of robust manufacturing methods that are scalable, cheap, and environmentally friendly. Herein, we address this challenge by developing a microfluidic approach that produces surfactant-free Pd nanocrystals (NCs) uniformly loaded on N-doped porous carbon in a one-batch process. The deep eutectic solvent (DES) prepared from choline chloride and ethylene glycol was employed as a novel synthesis solvent, and its extended hydrogen networks and abundant ionic species effectively stabilize Pd facets and confine nanocrystal sizes without using surfactants. The microreactors provide faster heat exchange and more uniform mass transport, which in combination with DES produced Pd NCs with better-defined shape and predominately exposed Pd (100) facet. Furthermore, we describe that the N-doped functional groups in porous carbon direct dense and uniform heterogeneous growth of Pd NCs in a one-batch process, thereby eliminating a separate catalyst deposition step that is often involved in conventional synthesis. The Pd NCs in the one-batch-produced Pd/C catalysts exhibited a size distribution of ∼13 ± 3.5 nm and a high ESCA of 46.0 m2/g and delivered 362 mA/mg for formic acid electrochemical oxidation with improved stability, demonstrating the unique potentials of microfluidic reactors and DES for the controllable and scalable synthesis of electrocatalyst materials for practical applications.

From Sodium-Oxygen to Sodium-Air Battery: Enabled by Sodium Peroxide Dihydrate.

Metal-air batteries have attracted extensive research interests due to their high theoretical energy density. However, most of the previous studies were limited by applying pure oxygen in the cathode, sacrificing the gravimetric and volumetric energy density. Here, we develop a real sodium-"air" battery, in which the rechargeability of the battery relies on the reversible reaction of the formation of sodium peroxide dihydrate (Na2O2·2H2O). After an oxygen evolution reaction catalyst is applied, the charge overpotential is largely reduced to achieve a high energy efficiency. The sodium-air batteries deliver high areal capacity of 4.2 mAh·cm-2 and have a decent cycle life of 100 cycles. The oxygen crossover effect is largely suppressed by replacing the oxygen with air, whereas the dense solid electrolyte interphase formed on the sodium anode further prolongs the cycle life.

Application of chromosome microarray analysis in patients with unexplained developmental delay/intellectual disability in South China.

BACKGROUND AND METHODS: Chromosome microarray analysis (CMA) is currently the first-tier diagnostic assay for the evaluation of developmental delay (DD) and intellectual disability (ID) with unknown etiology. Here, we present our clinical experience in implementing whole-genome high-resolution single nucleotide polymorphism (SNP) arrays to investigate 489 patients with unexplained DD/ID in whom standard karyotyping analyses showed normal karyotypes. This study aimed to assess the usefulness of CMA for clinical diagnostic testing in the Chinese population. RESULTS: A total of 489 children were classified into three groups: isolated DD/ID (n = 358), DD/ID with epilepsy (n = 49), and DD/ID with other structural anomalies (n = 82). We identified 126 cases (25.8%, 126/489) of pathogenic copy number variants (CNVs) by CMA, including 89 (24.9%, 89/358) with isolated DD/ID, 13 (26.5%, 13/49) with DD/ID with epilepsy, and 24 (29.3%, 24/82) with DD/ID with other structural anomalies. Among the 126 cases of pathogenic CNVs, 79 cases were identified as microdeletion/microduplication syndromes, among which 76 cases were classified as common syndromes, and 3 cases were classified as rare syndromes, including 15q24 microdeletion syndrome, Xq28 microduplication syndrome and Lowe syndrome. Additionally, there were forty-seven cases of non-syndromic pathogenic CNVs. The ABAT, FTSJ1, DYNC1H1, and SETBP1 genes were identified as DD/ID candidate genes. CONCLUSION: Our findings suggest the necessity of CMA as a routine diagnostic test for unexplained DD/ID in South China.

[Application of chromosome microarray analysis in 489 children with developmental delay/intellectual disability].

OBJECTIVE: To assess the value of chromosome microarray analysis (CMA) for identifying the etiology of developmental delay/intellectual disability (DD/ID). METHODS: A total of 489 children referred for DD/ID with or without other abnormalities were recruited. All patients showed a normal karyotype. DNA was extracted and hybridized with Affymetrix CytoScan 750K array by following the manufacturer's protocol. The data was analyzed with CHAS v2.0 software. RESULTS: The children were classified as with isolated DD/ID (n=358), DD/ID with epilepsy (n=49), and DD/ID with other structural anomalies (n=82). Pathogenic copy number variants (CNVs) were identified in 126 cases (25.8%), which included 89 (24.9%, 89/358) of whose with isolated DD/ID, 13 (26.5%, 13/49) of those with DD/ID and epilepsy, and 24 (29.3%, 24/82) of whose with DD/ID and other structural anomalies [P=0.064 (24.9% vs. 26.5%), P=0.679 (24.9% vs. 29.3%), and P=0.113 (26.5% vs. 29.3%), respectively]. Among the 126 cases, 79 were identified as microdeletion/microduplication syndromes, which included 15q24 microdeletion syndrome, Xq28 microduplication syndrome, and Lowe syndrome. Forty-seven cases had de novo pathogenic CNVs. ABAT, PMM2, FTSJ1, DYNC1H1 and SETBP1 were considered as candidate genes for DD/ID. CONCLUSION: CMA is an effective method for identifying the etiology of DD/ID and is capable of identifying microdeletion/microduplication syndromes as well as de novo pathogenic CNVs which may be missed by conventional karyotyping. Based on the results, candidate genes for DD/ID may be identified.

Whole-exome sequencing for prenatal diagnosis of fetuses with congenital anomalies of the kidney and urinary tract.

BACKGROUND: In the absence of cytogenetic abnormality, fetuses with congenital anomalies of the kidney and urinary tract (CAKUT) with/without other structural anomalies show a higher likelihood of monogenic causes; however, defining the underlying pathology can be challenging. Here, we investigate the value of whole-exome sequencing (WES) in fetuses with CAKUT but normal findings upon karyotyping and chromosome microarray analysis. METHODS: WES was performed on DNA from the cord blood of 30 fetuses with unexplained CAKUT with/without other structural anomalies. In the first 23 cases, sequencing was initially performed on fetal DNA only; for the remaining seven cases, the trio of fetus, mother and father was sequenced simultaneously. RESULTS: Of the 30 cases, pathogenic variants were identified in 4 (13%) (UMOD, NEK8, HNF1B and BBS2) and incidental variants in 2 (7%) (HSPD1 and GRIN2B). Furthermore, two of the above four cases had other anomalies in addition to CAKUT. Thus, the detection rate was only 2/22 (9.1%) for isolated CAKUT and 2/8 (25%) for CAKUT with other abnormalities. CONCLUSIONS: Applying WES to the prenatal diagnostic approach in CAKUT fetuses with or without other anomalies allows for an accurate and early etiology-based diagnosis and improved clinical management. To expedite interpretation of the results, trio sequencing should be employed; however, interpretation may nevertheless be compromised by incomplete coverage of all relevant genes.

High-Performance Rh2P Electrocatalyst for Efficient Water Splitting.

The search for active, stable, and cost-efficient electrocatalysts for hydrogen production via water splitting could make a substantial impact on energy technologies that do not rely on fossil fuels. Here we report the synthesis of rhodium phosphide electrocatalyst with low metal loading in the form of nanocubes (NCs) dispersed in high-surface-area carbon (Rh2P/C) by a facile solvo-thermal approach. The Rh2P/C NCs exhibit remarkable performance for hydrogen evolution reaction and oxygen evolution reaction compared to Rh/C and Pt/C catalysts. The atomic structure of the Rh2P NCs was directly observed by annular dark-field scanning transmission electron microscopy, which revealed a phosphorus-rich outermost atomic layer. Combined experimental and computational studies suggest that surface phosphorus plays a crucial role in determining the robust catalyst properties.

Enhanced Performance of Si MIS Photocathodes Containing Oxide-Coated Nanoparticle Electrocatalysts.

Electrodepositing low loadings of metallic nanoparticle catalysts onto the surface of semiconducting photoelectrodes is a highly attractive approach for decreasing catalyst costs and minimizing optical losses. However, securely anchoring nanoparticles to the photoelectrode surface can be challenging-especially if the surface is covered by a thin insulating overlayer. Herein, we report on Si-based photocathodes for the hydrogen evolution reaction that overcome this problem through the use of a 2-10 nm thick layer of silicon oxide (SiOx) that is deposited on top of Pt nanoparticle catalysts that were first electrodeposited on a 1.5 nm SiO2|p-Si(100) absorber layer. Such insulator-metal-insulator-semiconductor (IMIS) photoelectrodes exhibit superior durability and charge transfer properties compared to metal-insulator-semiconductor (MIS) control samples that lacked the secondary SiOx overlayer. Systematic investigation of the influence of particle loading, SiOx layer thickness, and illumination intensity suggests that the SiOx layer possesses moderate conductivity, thereby reducing charge transfer resistance associated with high local tunneling current densities between the p-Si and Pt nanoparticles. Importantly, the IMIS architecture is proven to be a highly effective approach for stabilizing electrocatalytic nanoparticles deposited on insulating overlayers without adversely affecting mass transport of reactant and product species associated with the hydrogen evolution reaction.