CoP Nanoparticles in Situ Grown in Three-Dimensional Hierarchical Nanoporous Carbons as Superior Electrocatalysts for Hydrogen Evolution

The development of efficient and low-cost hydrogen evolution reaction (HER) catalysts is critical for storing energy in hydrogen via water splitting but still presents great challenges. Herein, we report synthesis of three-dimensional (3-D) hierarchical nanoporous carbon (HNC) supported transition metal phosphides (TMPs) for the first time by in situ growth of CoP nanoparticles (NPs) in CaCO₃ NP-templated <i>Cinnamomum platyphyllum</i> leaf extract-derived carbon. They were subsequently employed as a HER catalyst, showing an onset potential of 7 mV and an overpotential of 95.8 mV to achieve 10 mA cm^–2, a Tafel plot of 33 mV dec^–1, and an exchange current density of 0.1182 mA cm^–2, of which the onset overpotential and the Tafel plot are the lowest reported for non-noble-metal HER catalysts, and the overpotential to achieve 10 mA cm^–2 and the exchange current density also compare favorably to most reported HER catalysts. In addition, this catalyst exhibits excellent durability with negligible loss in current density after 2000 CV cycles ranging from +0.01 to −0.17 V vs RHE at a scan rate of 100 mV s^–1 or 22 h of chronoamperometric measurement at an overpotential of 96 mV and a high Faraday efficiency of close to 100%. This work not only creates a novel high-performance non-noble-metal HER electrocatalyst and demonstrates the great advantages of the in situ grown 3-D HNC supported TMP NPs for the electrocatalysis of HER but also offers scientific insight into the mechanism for the in situ growth of TMP and their precursor NPs, in which an ultralow reactant concentration and rich functional groups on the 3-D HNC support play critical roles

N2 adsorption-desorption isotherms from Effects of sintering temperature on sensing properties of WO₃ and Ag-WO₃ electrode for NO₂ sensor

N2 adsorption-desorption isotherm

Heatmap of the 145 rhythmic probe sets in series 2 microarray data.

<p>Series 2 natural scale expression values for the 145 probe sets that were rhythmic in both series of data (<i>p</i><0.1 by JTK_CYCLE) were plotted. Phases were sorted by the “lag” values given by JTK_CYCLE.</p

Heatmap of pancreatic exocrine enzyme-related probe sets in series 2 data.

<p>Normalized log2 scale expression values for the probe sets representing transcripts related to pancreatic exocrine enzymes and zymogen secretion from series 2 data were plotted. Log2 scale data were used to facilitate viewing of all expression peaks. More dramatic variations in expression peaks in natural scale data led to improper viewing of those peaks on heatmap.</p

Heatmap of 66 probe sets representing clock and known rhythmic genes.

<p>Natural scale expression values from series 2 data for core clock genes and genes known to be rhythmically expressed in the adult liver were plotted with Heatmap builder. Some genes were represented by multiple probe sets. Phases were sorted by the “lag” values given by JTK_CYCLE.</p

Semi-quantitative RT-PCR analyses of pancreatic exocrine enzymes-related transcripts in fetal liver tissues.

<p>Equal amounts of starting RNA from the 12 time points of series 2 fetal liver tissues were reverse transcribed and subject to semi-quantitative PCR. PCR cycles were adjusted depending on transcripts abundance. Products were visualized by agarose gel electrophoresis.</p

Comparisons between fetal and adult liver transcriptomes.

<p>(<b>A</b>) Scatterplot of normalized and scaled average expression values in fetal (y-axis, series 2) and adult (x-axis) livers. Pairwise values for 22626 probe sets were plotted. <i>r</i> = 0.67, <i>P</i> = <0.01. (<b>B</b>) Fold differences in normalized and scaled average expression values between fetal (series 2) and adult (GSE11923) livers for 22626 probe sets. Ratios (fetal: adult) were plotted against their ranks.</p

Differential expression of clock genes between fetal and adult livers.

<p>Relative expression levels of selected clock genes, as detected by real-time RT-PCR results analyses on. Delta Ct values were converted to fold differences assuming amplification efficiency of 1.0. Adult expression level for each gene was set at 1.0.</p

Semi-quantitative RT-PCR analyses on selected transcripts differentially expressed between fetal and adult livers.

<p>Equal amounts of starting RNA were reverse transcribed and subject to semi-quantitative PCR. PCR cycles were adjusted depending on transcripts abundance. Fetal (series 1 and 2: F1 and F2) and adult liver (A) PCR results were compared by agarose gel electrophoresis. Negative controls (N) were performed by using no RT templates. All PCR products were sequence confirmed.</p

DataSheet1_Enhanced US/CT/MR imaging of integrin αvβ3 for liver fibrosis staging in rat.docx

Liver fibrosis is a global health challenge with high morbidity and mortality rates, and diagnostic sensitivity of liver fibrosis tests can be increased using multimodal molecular agents. We designed cyclic arginine-glycine-aspartic acid (cRGD)-modified nanoparticles (NPs) using ultrasound (US)/computed tomography (CT)/magnetic resonance (MR) triple-modality imaging to evaluate liver fibrosis stages. In vitro and in vivo studies were conducted using primary hepatic stellate cells (HSCs) and a rat model of liver fibrosis induced by carbon tetrachloride (CCl4). Our results showed cRGD-poly(lactic-co-glycolic acid)-Fe3O4-perfluorocarbon bromide (cRGD-PLGA-Fe3O4-PFOB) NPs were preferentially internalised by activated HSCs (aHSCs). The main cell types expressing integrin αvβ3 during liver fibrogenesis were the aHSCs. The protein levels of αv and β3 expressed on aHSCs increased with the progression of liver fibrosis. After intravenous injection of cRGD-PLGA-Fe3O4-PFOB NPs, the echo intensity (EI) values, CT values, and T2 values of liver parenchyma correlated well with liver fibrosis severity. cRGD-PLGA-Fe3O4-PFOB NPs as multifunction contrast agents showed great potential to reflect the degree of HSC activation and distinguish among different liver fibrotic stages. The ligand-directed and integrin αvβ3-mediated accumulation provides active and passive targeting capabilities, permitting the targeted multimodal imaging of cRGD-PLGA-Fe3O4-PFOB NPs, which delivers accurate non-invasive diagnosis and real-time monitoring of liver fibrosis development.</p