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InP/ZnS core/shell quantum dots have shown extraordinary application potential in photocatalysis. In this work, we demonstrated by ultrafast spectroscopy that the electron transfer ability of InP/ZnSe/ZnS core/shell/shell quantum dots was better than that of InP/ZnS quantum dots, because the introduction of ZnSe midshell resulted in improved passivation and greater exciton delocalization. The temperature-dependent PL spectra indicate that the exciton-phonon coupling strength and exciton binding energy of InP/ZnSe/ZnS quantum dots are smaller than those of InP/ZnS quantum dots. Further photocatalytic hydrogen evolution testing revealed that the photocatalytic activity of InP/ZnSe/ZnS quantum dots was significantly higher than that of InP/ZnS quantum dots, and InP/ZnSe/ZnS quantum dots even demonstrated improved stability. This research deepened our understanding of carrier dynamics and charge separation of InP/ZnSe/ZnS quantum dots, especially highlighting the application potential of InP/ZnSe/ZnS quantum dots in photocatalytic hydrogen evolution.

Graphite carbon nitride (g-C

Reduced graphene oxide (rGO) has conspicuous photothermal characteristics in photothermal applications. Thus in our previous work, we used reduced graphene oxide (rGO) supported titanium dioxide (TiO2) nanocomposite (rGO/TiO2) to absorb the ultraviolet and infrared light in the photothermal hydrogen evolution process. In order to make use of the full spectrum solar energy into other clear energy, the visible light should be also considered in following research. Herein, we report a cuprous oxide (Cu2O) decorated reduced graphene oxide (rGO) supported titanium dioxide (TiO2) (Cu2O-rGO/TiO2) catalysts, which can absorb full spectrum solar light in an innovative way. The Cu2O-rGO/TiO2 catalyst is synthesized through a one-step hydrothermal method. The rates of hydrogen evolution are 17800 μmol·g-1 h-1 under photothermal condition (90°C), 3800 μmol·g-1 h-1 under photocatalysis condition only (25°C) and 0 μmol·g-1 h-1 under thermal catalysis condition only. The result of photothermal catalytic hydrogen evolution rate is about 4.7 times that of the sum of the photocatalytic and thermal reactions. The photothermal synergetic effect promotes the photo-generated electron-holes separation through the rGO due to the temperature rising, and accelerates the reaction rates on the catalyst surface in hydrogen evolution process simultaneously. This work could provide us a new promising way for the conversion of full spectrum solar energy to hydrogen energy.

A kind of graphitic carbon nitride (TSC−550) with high polymerization degree and improved surface property was prepared by a new precursor of thiosemicarbazide. The sulfur motif and high nitrogen content in thiosemicarbazide promoted the polymerization of thiosemicarbazide to form graphitic carbon nitride framework with high degree of polymerization, which significantly influenced the electronic structure and surface chemical properties. TSC−550 possessed a narrow bandgap of 2.19 eV that facilitated the utilization of visible light, and possessed a less positive charge, acidic surface that resulted in enhanced hydrogen adsorption ability in water solution, which promoted the H2 evolution kinetics. In addition, the extended π-conjugated electronic system promoted the separation and migration of photo-generated charge carries in plane of TSC−550 framework, as well as the increasing interlayer C–N interactions in TSC−550 created conductive paths across the layers to tunnel interlayers for rapid electron transportation. As a result, TSC−550 nanosheets showed excellent photocatalytic H2 production activity, the AQY achieved 36.4% at 425 nm.

CoP, a noble-metal-free cocatalyst, was first introduced onto the surface of Al-doped SrTiO3 (Al:STO) via an in situ photodeposition-phosphorization method for photocatalytic overall water splitting (POWS) into stoichiometric H2 and O2. Compared with pure Al:STO, the POWS activity was enhanced by a factor of ~ 421 over 1.0%CoP/Al:STO, with the highest evolution rates of 2106 and 1002 μmol h−1 g−1 for H2 and O2, respectively. The mechanism for the remarkably boosted POWS activity was systematically analyzed based on the comprehensive characterization. On the one hand, benefiting from the in situ photodeposition process, CoP with metallic character were intimately decorated onto the surface of Al:STO and accelerated the separation and migration of photoinduced charge carriers. On the other hand, CoP, serving as reactive sites for H2 evolution reaction, lowered the overpotential and facilitated the surface reduction reaction, thereby enhancing the POWS activity. Furthermore, Cr2O3 was photodeposited on the surface of 1.0%CoP/Al:STO composite to suppress the undesired reverse reaction and the POWS activity was further enhanced up to 3558 and 1722 μmol h−1 g−1 for H2 and O2, respectively, with apparent quantum yield of 7.1% at 350 ± 10 nm. This work presents a new avenue for designing POWS system without noble-metal cocatalyst.

Domain-related knowledge promoted high-throughput cage scaffold screening from the ZINC15 database containing over 130 000 scaffolds and cooperated with combinatorial design to alleviate the lack of cage energetic materials. A dozen candidates were discovered that show excellent energy and safety performance, confirming the effectiveness of our strategy.

The bridging N atom in g-C3N4 structure plays a decisive role in photo-generated charge transfer because it usually confines photo-generated electrons and holes in each heptazine, thus leading to severe recombination. In this work, a kind of 2-aminoterephthalic acid-derived benzene ring group with rich π-electrons was considered to integrate with bridging N to break the above-mentioned confining effect. On the basis of density-functional theory calculations and experimental analysis, this 2-aminoterephthalic acid-derived bridging structure facilitated to draw photo-generated charge out of heptazine unit, and its polarized asymmetric structure promoted the directional transfer of photo-generated charge carriers across adjacent heptazines, thus efficiently reducing the recombination. Meanwhile, the 2-aminoterephthalic acid-derived bridging structure also reinforced the connectivity of heptazine units in g-C3N4 framework and led to high degree of polymerization, which thus extended the π-conjugated electronic system of g-C3N4 and modulated the band structure favoring photocatalytic hydrogen production. Consequently, a high photocatalytic H2-production activity of 24,595 μmol h−1 gcat-1 was achieved on the bridging regulated g-C3N4 under visible light, with an apparent quantum yield of 48.7% at 425 nm.

Photocatalytic O2-generation reaction is recognized as a crucial step in water splitting and has drawn great attention of researchers. In this work, a hetero-layered composite photocatalyst was successfully prepared by a facile self-assembly method based on electrostatic interaction between oppositely charged Zn/Cr-layered double hydroxide (Zn/Cr-LDH) and lead niobate nanosheets. The layer-by-layer stacking of Zn/Cr-LDH and HPb2Nb3O10 nanosheets was beneficial for rapid migration of photo-induced charge carriers inside the photocatalyst because of large contact area. In the meantime, Zn/Cr-LDH and HPb2Nb3O10 components exhibited suitable energy-band alignment, which led to efficient separation of photo-induced charge carriers. The composite photocatalyst showed enhanced photocatalytic O2-generation activity under visible-light irradiation without loading cocatalyst. Briefly, this work expanded the applications of AB2Nb3O10-based materials in photocatalytic energy conversion and proved that constructing composites based on electrostatic self-assembly of complementary 2D materials is a promising strategy for development of more efficient photocatalysts.

Due to structural tunability, high surface area, abundant pore structures, and abundant active sites, covalent heptazine frameworks (CHFs) constructed from heptazine and other molecular blocks are especially prominent. Here, we proposed a reaction-dependent strategy for designing two dimensional CHFs including high-throughput precursors screening, structure generation, and performance evaluation. Assuming that oxamide-like precursors can undergo the same thermal polymerization reaction as producing C

While precision medicine driven by genome sequencing has revolutionized cancer care, such as lung cancer, its impact on gastric cancer (GC) has been minimal. GC patients are routinely treated with chemotherapy, but only a fraction of them receive the clinical benefit. There is an urgent need to develop biomarkers or algorithms to select chemo-sensitive patients or apply targeted therapy. Here, we carried out retrospective analyses of 1,020 formalin-fixed, paraffin-embedded GC surgical resection samples from 5 hospitals and developed a mass spectrometry-based workflow for proteomic subtyping of GC. We identified two proteomic subtypes: the chemo-sensitive group (CSG) and the chemo-insensitive group (CIG) in the discovery set. The 5-year overall survival of CSG was significantly improved in patients who had received adjuvant chemotherapy after surgery compared with those who received surgery only (64.2% vs. 49.6%; Cox P-value=0.002), whereas no such improvement was observed in CIG (50.0% vs. 58.6%; Cox P-value=0.495). We validated these results in an independent validation set. Further, differential proteome analysis uncovered 9 FDA-approved drugs that may be applicable for targeted therapy of GC. A prospective study is warranted to test these findings for future GC patient care.

In this study, CuO–ZnO and Fe2O3–Cr2O3 were prepared by coprecipitation and their catalytic activity in supercritical water gasification (SCWG) was evaluated at 500 and 600 °C. Both catalysts impro...

In industrial applications, the phenomenon of scCO2 (supercritical carbon dioxide) flowing over particles is quite common. Considering that the scCO2 is chemically inactive but has high solubility, the pure Stefan flow will present without the related diffusion of a chemical reaction component and reaction heat, during the process of a spherical particle in the solid phase dissolved in a system of scCO2. To this, particle resolve-direct numerical simulation without considering the role of gravity and buoyancy is employed in this paper to investigate the high-temperature scCO2 flowing over a low-temperature stationary sphere with the uniformly, normally, and outward distributed Stefan flow on its surface, with the above cases conducted in the process of small variations on physical properties of scCO2. We present a series of variables in the flow field and temperature field near the sphere surface to study the effects of Stefan flow on them compared with cases without Stefan flow. Related distribution details of the velocity boundary layer and the temperature boundary layer near the sphere surface under conditions with or without the Stefan flow are also presented and analyzed. Different from other similar studies, our study also pays more attention to variables of the local fluid field as well as temperature field near the surface of the spherical particle. The results show that the presence of Stefan flow will reduce flow resistance of the freestream but inhibits heat transfer performance. Simpler correlations in form compared with previous well-established correlations are presented and are used to describe the operating conditions proposed herein.

Violates containing polycyclic aromatic hydrocarbons (PAHs) were precipitated in the process of fast pyrolysis and gasification of coal and organic substances. PAHs are one of bottlenecks of entire coal gasification for hydrogen production. In current work, the solubility of PAH oil droplets in supercritical water/hydrogen circumstances were investigated based on molecular dynamics simulation, which was beneficial for understanding the solubility behaviors of PAHs in supercritical water/hydrogen environment. The results showed that heavy PAHs were rather stable in the water phase. Supercritical water along with hydrogen promoted the miscibility of PAHs compared with that of pure supercritical water. Furthermore, high density and high temperature facilitated the rapid solvation of PAHs in supercritical water/hydrogen environment. This paper is expected to provide a theoretical support for the development of complete coal gasification technology for hydrogen production.

A 2D/2D coupled NiCo2O4/g-C3N4 nanostructure was fabricated through an in situ growth strategy. NiCo2O4 worked as a novel oxygen-evolution-reaction cocatalyst, and the intimate interface combination by surface bonding and the related cooperative effect between NiCo2O4 and g-C3N4 were comprehensively explored. Consequently, the separation and migration of photo-generated charge carriers for g-C3N4 were efficiently promoted, as well as the energy barriers of the oxygen evolution reaction were reduced. NiCo2O4/g-C3N4 showed obviously enhanced photocatalytic O2-evolution activity (4.6 times that of bare g-C3N4), and the corresponding AQY achieved 4.9% at 380 nm. Then, Pt as a hydrogen-evolution-reaction cocatalyst was employed to cooperate with NiCo2O4 to construct dual cocatalyst loaded g-C3N4 for photocatalytic overall water splitting, in which H2 and O2 simultaneously evolved in a stoichiometric ratio of 2 : 1, and the AQY for H2 evolution reached 2.8% at 380 nm. Consequently, this work demonstrates a reliable strategy for g-C3N4 to construct a photocatalytic system for efficient overall water splitting.

Supercritical water gasification is an innovative handling method of black liquor, which can also produce hydrogen-rich gases. In this study, the catalytic activity of 14 common metal oxides on SCWG of black liquor were investigated and the catalytic mechanism was studied through X-ray photoelectron spectroscopy (XPS) analysis. All the tested oxides improved the gasification efficiency and V2O5, WO3 and Co2O3 showed the highest performance. The H2 yields of 21.67 and 21.03 mol/kg were achieved with the presence of Co2O3 and ZnO respectively. The gasification efficiency increased with the increasing V2O5 amount, but the H2 fraction increased firstly and then decreased. The highest H2 fraction of 44.59% was obtained with V2O5 loading amount of 45 wt%. The increase of reaction time improved the CE, but the further prolongation had little influence. The XPS analysis of CuO and Fe2O3 showed some of them were reduced to metal (Cu) or lower-valence oxides (Cu2O, FeO). The metal oxides probably promoted black liquor decomposition by introducing reactive oxygen, and the generated metal also catalyzed the gasification. Accordingly, an oxidation reactor could be introduced to recycle the metal oxides, which may help to realize the complete gasification of black liquor or other refractory wastes at milder temperatures.

Plastic pollution is one of the most important environmental issues being faced today. In this work, the hydrothermal liquefaction performance of polycarbonate (PC) in sub-/supercritical water was investigated using a quartz tube reactor. Response surface methodology (RSM) was employed to demonstrate the correlation between reaction conditions and liquefaction efficiency of PC. The conversion selectivity and product recovery efficiency of PC were also analyzed. Moreover, according to the experimental results, the liquefaction reaction pathways of PC were speculated. In addition, based on the established reaction pathways, the lumped parameter method was also used to calculate the liquefaction kinetics of PC. The results showed that phenol was the largest liquefied product of PC, followed by 4-isopropylphenol (IPrP) and 4-isopropenylphenol (IPP), and the recovery efficiency of these three components determined the level of liquefaction efficiency. The PC liquefaction favored a mild reaction temperature, long residence time, and low feedstock concentration. Finally, for identified products, a 57.70 wt % carbon liquefaction efficiency was obtained with a 5 wt % feedstock concentration at 400 °C for 60 min. The liquefaction pathways showed that in the initial stage of depolymerization, 4-tert-butylphenol was first formed as a structural regulator, and phenol and IPP were the primary liquefied products. The IPrP, 4-ethylphenol, and p-cresol were the secondary products. The kinetic results indicated that the liquefied intermediates were easily converted to form phenol and IPP, and the IPP and IPrP were not directly converted to phenol, but there was a clear conversion relationship between them.

Design of 2D/2D photocatalysts with strong interfacial interaction via abundant 2D coupling interfaces has been proved to be an efficient strategy to promote photocatalytic performance. Herein, colloidal suspensions containing HCa2Nb3O10 nanosheets (HCNO) and dicyandiamide were adopted as feed reagents, based on which 2D/2D HCa2Nb3O10 nanosheet/g-C3N4 composites (HCNO/CN) with efficient photocatalytic activities were synthesized by a facile one-pot method. By this way, the separation process of HCa2Nb3O10 nanosheets was eliminated and the effective heterojunction formed simultaneously. The optimal visible light-driven photocatalytic H2-evolution activity of the composite photocatalysts was 4.5 times that of pristine g-C3N4 (CN), and the enhanced photocatalytic activities were attributed to the following aspects. On the one hand, the large 2D contact interfaces and the matched energy bands resulted in an efficient type II heterojunction and it thus could accelerate the separation and transfer of photo-generated electron–hole pairs. On the other hand, the residual tetrabutylammonium hydroxide on HCNO obviously changed the structure of g-C3N4 by the in situ pyrolysis strategy, thus enhancing the light absorption, narrowing the bandgap and enlarging the specific surface area and pore volume of g-C3N4. This work presents an effective and convenient route to construct 2D/2D composite photocatalysts based on layered perovskite nanosheets and/or g-C3N4 nanosheets, by which the compositions and microstructures of the composites were optimized simultaneously during the pyrolysis process.