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Charge separation is critical for achieving efficient solar-to-hydrogen conversion, whereas piezoelectric-enhanced photoelectrochemical (PEC) systems can effectively modulate band bending and charge migration. Herein, we design an n-TiO2/BaTiO3/p-TiO2 (TBTm) heterojunction in which the piezoelectric BaTiO3 layer is sandwiched between n-TiO2 and p-TiO2. The built-in electric field of TBTm can provide a strong driving force to accelerate carrier separation and prolong carrier lifetime. Consequently, the TBT3 achieves a prominent photocurrent density, as high as 2.13 mA cm−2 at 1.23 V versus reversible hydrogen electrode (RHE), which is 2.4- and 1.5-times higher than TiO2 and TiO2–BaTiO3 heterojunction, respectively. Driven by mechanical deformation, the induced dipole polarization can further regulate built-in electric fields, and the piezoelectric photocurrent density of TBT3-800 is 2.84 times higher than TiO2 at 1.23 V vs. RHE due to the construction of piezoelectric-heterostructures. This work provides a piezoelectric polarization strategy for modulating the built-in electric field of heterojunction for PEC system.

BackgroundThe main challenges faced when using sirolimus in children with vascular anomalies (VAs) still include significant pharmacokinetic (PK) variability, uncertainty in the target concentration range, as well as inconsistencies in initial dosing and dosing frequency. The aim of this study is to establish a new population pharmacokinetic (PPK) model for children with VAs to guide the individualized use of sirolimus.MethodsA PPK study was performed using data from children with VAs who received sirolimus between July 2017 and April 2022. A nonlinear mixed-effect modeling with a one-compartment model structure was applied. Monte Carlo simulation was employed to propose specific dosing recommendations to achieve the target trough concentrations (Ctrough) of 5–15 ng/mL.ResultsIn total, 134 blood concentrations from 49 pediatric patients were used to characterize the sirolimus pharmacokinetics. Covariate analysis identified body weight (BW) as a significant factor affecting clearance (CL) in the final PPK model. The typical clearance rate and distribution volume, standardized to a BW of 16 kg, were 4.06 L/h (4% relative standard error, RSE) and 155 L (26% RSE), respectively. Optimal dosing regimens were simulated for different BWs. For a twice-daily regimen, the recommended doses were 0.05, 0.06, 0.07, and 0.08 mg/kg/day for BW of

The advancement in electrocatalysis, particularly in the development of efficient catalysts for hydrogen and oxygen evolution reactions (HER and OER), is crucial for sustainable energy generation through processes like overall water splitting. A notable bifunctional electrocatalyst, CoFe2O4/Co7Fe3, has been engineered to facilitate both OER and HER concurrently, aiming to reduce overpotentials. In the pursuit of further enhancing catalytic efficiency, a morphological transformation has been achieved by introducing a sulphur source and multi-walled carbon nanotubes (MWCNTs) into the catalyst system, resulting in S–CoFe2O4/Co7Fe3/MWCNTs. This modification has significantly improved the activity for both OER and HER. An onset overpotential of 250 mV@10 mAcm−2 for the OER and 270 mV@50 mAcm−2 for the HER, indicating efficient catalytic activity at relatively low overpotentials. S–CoFe2O4/Co7Fe3/MWCNTs display an outstanding long-term stability in alkaline electrolytes, with minimal Tafel slopes of 77 mV/dec for the OER and 70 mV/dec for the HER, suggesting sustained catalytic performance over extended periods. Furthermore, when employed as both the cathode and anode in the context of complete water splitting, S–CoFe2O4/Co7Fe3/MWCNTs demonstrate an impressive cell voltage of 1.52 V at a current density of 10 mA cm−2 in a 1 M KOH solution, showcasing its viability for practical applications. Given its cost-effectiveness and superior activity, S–CoFe2O4/Co7Fe3/MWCNTs hold significant promise for widespread applications in overall water splitting electrocatalysis, contributing to the advancement of cleaner and sustainable fuel generation technologies.

Objectives: Sirolimus (SRL), a mammalian target of rapamycin inhibitor, has been widely used to treat patients with vascular anomalies (VAs). The objectives of this study were to summarize the routine blood SRL monitoring data for VAs children, to investigate the factors contributing to the variable blood SRL concentrations and to evaluate the efficacy and safety of SRL therapy. Methods: VAs patients with routine blood SRL monitoring from July 2017 to April 2022 at the Department of Burns and Plastic Surgery, Children’s Hospital of Nanjing Medical University were retrospectively collected. Clinical data were obtained from the hospital information system. Results: In total, 67 children (35 females) were enrolled. The therapeutic drug monitoring data showed that the range of measured blood trough concentrations (Ctrough) was 3.6–46.8 ng/mL. At the initial measurements, only 33% of patients were in the target concentration range (10–15 ng/mL). But this proportion became 54% at the last measurements. The whole blood-Ctrough-to-daily dose (Ctrough/Dose) ratio was significantly associated with age and body weight (BW). The patients’ laboratory results did not change significantly after SRL treatment. Although the incidence of adverse events was relatively high (44.8%), most of them were mild and tolerable. 70.3% patients had total responses to SRL, whereas 29.7% children exhibited stable disease or progressive disease. No significant differences were found in Ctrough between the total response group and non-response group. Conclusions: This retrospective study revealed a high variability in SRL blood concentrations in Chinese children with VAs. Of note, pediatric patients with older age and a higher BW had a lower Ctrough/Dose ratio. It is a concern whether the range of 10–15 ng/mL is feasible for Chinese children based only on our study. Further studies recruiting more patients are required to redefine the target reference range for children with VAs.

Abstract The spin degree of freedom is an important and intrinsic parameter in boosting carrier dynamics and surface reaction kinetics of photocatalysis. Here we show that chiral structure in ZnO can induce spin selectivity effect to promote photocatalytic performance. The ZnO crystals synthesized using chiral methionine molecules as symmetry-breaking agents show hierarchical chirality. Magnetic circular dichroism spectroscopic and magnetic conductive-probe atomic force microscopic measurements demonstrate that chiral structure acts as spin filters and induces spin polarization in photoinduced carriers. The polarized carriers not only possess the prolonged carrier lifetime, but also increase the triplet species instead of singlet byproducts during reaction. Accordingly, the left- and right-hand chiral ZnO exhibit 2.0- and 1.9-times higher activity in photocatalytic O2 production and 2.5- and 2.0-times higher activities in contaminant photodegradation, respectively, compared with achiral ZnO. This work provides a feasible strategy to manipulate the spin properties in metal oxides for electron spin-related redox catalysis.

Abstract Surface reconstruction generates real active species in electrochemical conditions; rational regulating reconstruction in a targeted manner is the key for constructing highly active catalyst. Herein, we use the high-valence Mo modulated orthorhombic Pr3Ir1−x Mo x O7 as model to activate lattice oxygen and cations, achieving directional and accelerated surface reconstruction to produce self-terminated Ir‒Obri‒Mo (Obri represents the bridge oxygen) active species that is highly active for acidic water oxidation. The doped Mo not only contributes to accelerated surface reconstruction due to optimized Ir‒O covalency and more prone dissolution of Pr, but also affords the improved durability resulted from Mo-buffered charge compensation, thereby preventing fierce Ir dissolution and excessive lattice oxygen loss. As such, Ir‒Obri‒Mo species could be directionally generated, in which the strong Brønsted acidity of Obri induced by remaining Mo assists with the facilitated deprotonation of oxo intermediates, following bridging-oxygen-assisted deprotonation pathway. Consequently, the optimal catalyst exhibits the best activity with an overpotential of 259 mV to reach 10 mA cmgeo −2, 50 mV lower than undoped counterpart, and shows improved stability for over 200 h. This work provides a strategy of directional surface reconstruction to constructing strong Brønsted acid sites in IrOx species, demonstrating the perspective of targeted electrocatalyst fabrication under in situ realistic reaction conditions.

Abstract Electrocatalytic oxygen reduction reaction (ORR) to prepare H2O2 in acidic medium has the advantages of green, safety, and portability, which shows broad development prospects. However, it still suffers from low catalyst activity, insufficient selectivity, and high cost. Herein, Pt1/CoSe2 with ultralow 0.01 wt.% Pt atomic distribution was synthesized by a simple hydrothermal method. The Pt1/CoSe2 with ultralow Pt content exhibits high activity, high selectivity, and long‐term stability for ORR to H2O2 in O2‐saturated 0.1 M HClO4. The onset potential is as low as 0.75 V versus reversible hydrogen electrode (RHE), H2O2 selectivity is as high as 84% (0.4 V vs. RHE), and the electron transfer number is 2.3 (0.4 V vs. RHE). Moreover, the hydrogen peroxide yield using the flow cell testing is 110.02 mmol gcat.−1 h−1 with high Faradaic efficiency of 78% (0 V vs. RHE) at 0.1 M HClO4, and the catalyst did not deactivate significantly after 60 h stability testing. Mechanistic studies and in situ X‐ray photoelectron spectroscopy characterization confirm that the ultralow Pt content on CoSe2 can effectively regulate the electronic structure of Co as the real active site around the Pt site, which gives a suitable ∆dp value (the difference between the d‐band center of the active metal site and the p‐band center of the terminal oxygen in *OOH), provides an ideal *OOH binding energy, and inhibits the O–O bond breakage. This work successfully improves the intrinsic activity of the Co active sites around Pt in Pt1/CoSe2 for acidic ORR to H2O2 by constructing ultralow‐content Pt single atom.

Abstract Lignin is the main component of lignocellulose and the largest source of aromatic substances on the earth. Biofuel and bio‐chemicals derived from lignin can reduce the use of petroleum products. Current advances in lignin catalysis conversion have facilitated many of progress, but understanding the principles of catalyst design is critical to moving the field forward. In this review, the factors affecting the catalysts (including the type of active metal, metal particle size, acidity, pore size, the nature of the oxide supports, and the synergistic effect of the metals) are systematically reviewed based on the three most commonly used supports (carbon, oxides, and zeolites) in lignin hydrogenolysis. The catalytic performance (selectivity and yield of products) is evaluated, and the emerging catalytic mechanisms are introduced to better understand the catalyst design guidelines. Finally, based on the progress of existing studies, future directions for catalyst design in the field of lignin depolymerization are proposed.

Abstract The development of efficient and economical electrocatalysts for oxygen evolution reaction (OER) is of paramount importance for the sustainable production of renewable fuels and energy storage systems; however, the sluggish OER kinetics involving multistep four proton‐coupled electron transfer hampers progress in these systems. Fortunately, surface reconstruction offers promising potential to improve OER catalyst design. Anion modulation plays a crucial role in controlling the extent of surface reconstruction and positively persuading the reconstructed species' performances. This review starts by providing a general explanation of how various types of anions can trigger dynamic surface reconstruction and create different combinations with pre‐catalysts. Next, the influences of anion modulation on manipulating the surface dynamic reconstruction process are discussed based on the in situ advanced characterization techniques. Furthermore, various effects of survived anionic groups in reconstructed species on water oxidation activity are further discussed. Finally, the challenges and prospects for the future development directions of anion modulation for redirecting dynamic surface reconstruction to construct highly efficient and practical catalysts for water oxidation are proposed.

The development of biomass fuels is of great significance for reducing excessive dependence on fossil resources and global warming. Lignin is a complex aromatic biopolymer that is abundant in nature and can be used to produce high-value biomass fuels. However, due to its complex structure, the use of lignin to produce biomass fuels needs a variety of chemical reactions and catalysts, and the intermediates and products need to be separated many times, resulting in a low yield of products. Multifunctional catalysts can catalyze two or more chemical reactions at the same time; therefore, using them can simplify the preparation process and increase the yield of products. This paper reviewed the research progress of multifunctional catalysts used in the process of lignin hydrocracking, monomer hydrodeoxygenation, and monomer upgrading to polycyclic high-value products, including sulfide catalysts, noble metal elemental catalysts, non-noble metal elemental and alloy catalysts, and phosphide catalysts. Additionally, this work emphasized the interaction between hydrogenation centers (Ru, Pt, Pd, Co, Mo, and Ni) and acid centers (Al2O3, ZrO2, NbOPO4, zeolite, and mesoporous silicate) in hydrocracking and hydrodeoxygenation. Based on these, the difficulties of the current reactions were then summarized, and the next technical developing directions were anticipated, including those of the development of biomass fuel synthesis methods with more mild reaction conditions and preparation of catalysts with higher activity, higher hydrothermal stability, and lower price. This paper hopes that new methods can reduce the amount of hydrogen, decrease the reaction temperature, and converse lignin to high-value fuels in a one-pot method. Moreover, most research on biomass fuels is still in the laboratory research stage. To realize the large-scale industrial production of biomass fuels and replace petroleum fuels, more in-depth research, perfect supporting facilities, and relevant policies and measures are needed.

Abstract The Haber–Bosch process for industrial NH3 production is energy‐intensive with heavy CO2 emissions. Electrochemical N2 reduction reaction (NRR) is an attractive carbon‐neutral alternative for NH3 synthesis, while the challenge associated with N2 activation highlights the demand for efficient electrocatalysts. Herein, we demonstrate that PdCu nanoparticles with different Pd/Cu ratios anchored on boron nanosheet (PdCu/B) behave as efficient NRR electrocatalysts toward NH3 synthesis. Theoretical and experimental results confirm that the highly efficient NH3 synthesis can be achieved by regulating the charge transfer between interfaces and forming a symmetry‐breaking site, which not only alleviates the hydrogen evolution but also changes the adsorption configuration of N2 and thus optimizes the reaction pathway of NRR over the separated Pd sites. Compared with monometallic Pd/B and Cu/B, the PdCu/B with the optimized Pd/Cu ratio of 1 exhibits superior activity and selectivity for NH3 synthesis. This study provides new insight into developing efficient catalysts for small energy molecule catalytic conversion via regulating the charge transfer between interfaces and constructing symmetry‐breaking sites.

Abstract The conversion of biomass is a favorable alternative to the fossil energy route to solve the energy crisis and environmental pollution. As one of the most versatile platform compounds, 5‐hydroxymethylfural (HMF) can be transformed to various value‐added chemicals via electrolysis combining with renewable energy. Here, the recent advances in electrochemical oxidation of HMF, from reaction mechanism to reactor design are reviewed. First, the reaction mechanism and pathway are summarized systematically. Second, the parameters easy to be ignored are emphasized and discussed. Then, the electrocatalysts are reviewed comprehensively for different products and the reactors are introduced. Finally, future efforts on exploring reaction mechanism, electrocatalysts, and reactor are prospected. This review provides a deeper understanding of mechanism for electrochemical oxidation of HMF, the design of electrocatalyst and reactor, which is expected to promote the economical and efficient electrochemical conversion of biomass for industrial applications.

Abstract As a new generation of high‐efficiency energy storage devices, lithium–sulfur (Li–S) battery attract increasing attention. However, slow conversion kinetics of lithium polysulfides (LiPSs) and severe shuttle effect are bottlenecks. Developing efficient sulfur host materials to suppress the shuttling of LiPSs and accelerate their conversion kinetics is a general strategy to enhance the performance of Li–S batteries. Herein, MoS2 quantum dots (QDs)@MgB2 nanosheet was synthesized using a simple liquid‐phase mixing method. The MoS2 QDs not only inhibit the stacking of MgB2 nanosheets but also expose more unsaturated metal active sites, which can effectively improve the adsorption of LiPSs, accelerate its catalytic conversion and suppress its shuttle effect. Moreover, MgB2 nanosheets can be used as polypropylene (PP) separator modifier. The battery using MoS2 QDs@MgB2 as the sulfur host material and MgB2@PP as the separator has high rate capability and excellent stability. In addition, the discharge‐specific capacity shows a good application prospect.

Abstract The excessive dependence on fossil fuels contributes to the majority of CO2 emissions, influencing on the climate change. One promising alternative to fossil fuels is green hydrogen, which can be produced through water electrolysis from renewable electricity. However, the variety and complexity of hydrogen evolution electrocatalysts currently studied increases the difficulty in the integration of catalytic theory, catalyst design and preparation, and characterization methods. Herein, this review first highlights design principles for hydrogen evolution reaction (HER) electrocatalysts, presenting the thermodynamics, kinetics, and related electronic and structural descriptors for HER. Second, the reasonable design, preparation, mechanistic understanding, and performance enhancement of electrocatalysts are deeply discussed based on intrinsic and extrinsic effects. Third, recent advancements in the electrocatalytic water splitting technology are further discussed briefly. Finally, the challenges and perspectives of the development of highly efficient hydrogen evolution electrocatalysts for water splitting are proposed.

Photocatalyst activity depends significantly on the material’s electronic structures. Here, authors manipulate the electron spin polarization of TiO2 by tuning the concentration of Ti vacancies and show improved photocatalytic activities.

Abstract For selective hydrogenation of chemicals the high selectivity is always at the expense of activity and improving both selectivity and activity is challenging. Here, by chelating with p‐fluorothiophenol (SPhF)‐arrays, both steric and electronic effects are created to boost the performance of cheap nickel‐based catalysts. Compared with dinickel phosphide, the SPhF‐chelated one exhibits nearly 12 times higher activity and especially its selectivity is increased from 38.1% and 21.3% to nearly 100% in hydrogenations of 3‐nitrostyrene and cinnamaldehyde. Commercial catalysts like Raney Ni chelating with SPhF‐array also exhibits an enhanced selectivity from 20.5% and 23.4% to ≈100% along with doubled activity. Both experimental and density functional theory (DFT) calculation prove that the superior performance is attributed to the confined flat adsorption by ordered SPhF‐arrays and downshifted d‐band center of catalysts, leading to prohibited hydrogenation of the vinyl group and accelerative H2 activation. Such a surface modification can provide an easily‐realized and low‐cost way to design catalysts for the selective hydrogenation.

Abstract Photocatalytic water splitting is promising for hydrogen energy production using solar energy and developing highly efficient photocatalysts is challenging. Defect engineering is proved to be a very useful strategy to promote the photocatalytic performance of metal‐based photocatalysts, however, the vital role of defects is still ambiguous. This work comprehensively reviews point defective metal‐based photocatalysts for water splitting, focusing on understanding the defects' disorder effect on optical adsorption, charge separation and migration, and surface reaction. The controllable synthesis and tuning strategies of defective structure to improve the photocatalytic performance are summarized, then the characterization techniques and density functional theory calculations are discussed to unveil the defect structure, and analyze the defects induced electronic structure change of catalysts and its ultimate effect on the photocatalytic activity at the molecular level. Finally, the challenge in developing more efficient defective metal‐based photocatalysts is outlined. This work may help further the understanding of the fundamental role of defect structure in the photocatalytic reaction process and guide the rational design and fabrication of highly efficient and low‐cost photocatalysts.

The d-band center position of the metal catalyst is one of the most important factors for catalytic selective hydrogenation, e.g., the conversion of nitrostyrene to aminostyrene. In this work, we modulate the d-band center position of the Pt surface via H coverage manipulation in order to assess the highly efficient selective hydrogenation catalyst using density functional theory (DFT) calculation, which is validated experimentally. The optimal transition metal catalysts are first screened by comparing the adsorption energy values of two ideal models, nitrobenzene and styrene, and by correlating the adsorption energy with the d-band center positions. Among the ten transition metals, Pt nanoparticles have a good balance between selectivity and the conversion rate. Then, the surface hydrogen covering strategy is applied to modulate the d-band center position on the Pt (111) surface, with the increase of H coverage leading to a decline of the d-band center position, which can selectively enhance the adsorption of nitro groups. However, excessively high H coverage (e.g., 75% or 100%) with an insufficiently low d-band center position can switch the chemisorption of nitro groups to physisorption, significantly reducing the catalytic activity. Therefore, a moderate d-band center shift (ca. −2.14 eV) resulted in both high selectivity and catalytic conversion. In addition, the PtSn experimental results met the theoretical expectations. This work provides a new strategy for the design of highly efficient metal catalysts for selective hydrogenation via the modulation of the d-band center position.

Charge separation is critical for achieving efficient solar-to-hydrogen conversion, whereas piezoelectric-enhanced photoelectrochemical (PEC) systems can effectively modulate band bending and charge migration. Herein, we design an n-TiO2/BaTiO3/p-TiO2 (TBTm) heterojunction in which the piezoelectric BaTiO3 layer is sandwiched between n-TiO2 and p-TiO2. The built-in electric field of TBTm can provide a strong driving force to accelerate carrier separation and prolong carrier lifetime. Consequently, the TBT3 achieves a prominent photocurrent density, as high as 2.13 mA cm2 at 1.23 V versus reversible hydrogen electrode (RHE), which is 2.4- and 1.5-times higher than TiO2 and TiO2-- BaTiO3 heterojunction, respectively. Driven by mechanical deformation, the induced dipole polarization can further regulate built-in electric fields, and the piezoelectric photocurrent density of TBT3-800 is 2.84 times higher than TiO2 at 1.23 V vs. RHE due to the construction of piezoelectric-heterostructures. This work provides a piezoelectric polarization strategy for modulating the built-in electric field of heterojunction for PEC system. [ABSTRACT FROM AUTHOR]

The development of efficient and economical electrocatalysts for oxygen evolution reaction (OER) is of paramount importance for the sustainable production of renewable fuels and energy storage systems; however, the sluggish OER kinetics involving multistep four proton-coupled electron transfer hampers progress in these systems. Fortunately, surface reconstruction offers promising potential to improve OER catalyst design. Anion modulation plays a crucial role in controlling the extent of surface reconstruction and positively persuading the reconstructed species' performances. This review starts by providing a general explanation of how various types of anions can trigger dynamic surface reconstruction and create different combinations with pre-catalysts. Next, the influences of anion modulation on manipulating the surface dynamic reconstruction process are discussed based on the in situ advanced characterization techniques. Furthermore, various effects of survived anionic groups in reconstructed species on water oxidation activity are further discussed. Finally, the challenges and prospects for the future development directions of anion modulation for redirecting dynamic surface reconstruction to construct highly efficient and practical catalysts for water oxidation are proposed. [ABSTRACT FROM AUTHOR]