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Piezocatalysis portrays a promising alternative for producing hydrogen (H2) and hydrogen peroxide (H2O2) in a clean and safe way, but the simultaneous enhancement of both properties remains challenging. In this study, a BiFeO3-based bifunctional piezocatalytic strategy via Sm doping and g-C3N4compositing (Bi0.98Sm0.02FeO3/g-C3N4) was proposed for efficient simultaneous H2and H2O2production. Benefiting from the synergistic effect between the optimized energy band structure and piezo-generated charges, the performances of hydrogen evolution reaction (HER) and water oxidation reaction (WOR) are both enhanced remarkably. As a result, the evolution rates of BSFO/g-C3N4for pure water splitting into H2and H2O2simultaneously reach 988 and 214 μmol g–1h–1without any sacrificial agent, which is 4.6 and 7.6 times higher than those of pure BiFeO3. Theoretical calculations reveal the critical role of this optimization in reducing the adsorption energy barriers of HER and WOR intermediates by factors of 10.83 and 12.38, respectively. This study broadens new insight into the design of efficient piezocatalysts for water splitting.

In carbon-based supercapacitors, redox couples can effectively improve the energy density of supercapacitors; however, most redox couples still suffer from serious shuttle diffusion. Currently, there is no universal strategy to effectively constrain their shuttle diffusion. Therefore, developing a simple, effective, and universal method to suppress shuttle diffusion remains a great challenge. Herein, we designed and prepared a hierarchical structure electrode composed of three functional layers (inner conductive layer, intermediate storage layer, and outer confinement layer) for redox-enhanced supercapacitors. The hierarchical electrode can be fabricated on a large scale in three simple steps based on commercial carbon felt. The rationally designed three functional layers endow the hierarchical structure electrode with excellent conductivity, adsorption capacity, and confinement ability. Long-term charge–discharge cycle results prove that the hierarchical structure electrode exhibits an outstanding restriction effectiveness on three redox media with different molecular sizes (anthraquinone (AQ), naphthoquinone (NQ), and p-benzoquinone (PQ)). Specifically, for AQ, NQ, and PQ, the hierarchical structure electrodes showed CV peak current attenuation rates of only 5.64%, 3.54%, and 10.34% after 5,000 cycles of charge–discharge, while common electrodes exhibited attenuation rates of 10.44%, 15.02%, and 20.20%, respectively. Moreover, the soft-pack supercapacitors composed of hierarchical electrodes still had a capacitance retention of 86.6% after 5,000 cycles of charge–discharge. All the results demonstrate that the structure design is reasonable and the hierarchical structure electrode has a great potential to be the universal electrode for suppressing the shuttle diffusion of redox media in supercapacitors and other energy storage devices.

Chemical vapor deposition (CVD) is a widely used method for graphene synthesis, but it struggles to produce large-area uniform bilayer graphene (BLG). This study introduces a novel approach to meet the demands of large-scale integrated circuit applications, challenging the conventional reliance on uniform BLG over extensive areas. We developed a unique method involving the direct growth of bilayer graphene arrays (BLGA) on Cu foil substrates using patterned titanium (Ti) as a diffusion barrier. The use of the Ti layer can effectively control carbon atom diffusion through the Cu foil without altering the growth conditions or compromising the graphene quality, thereby showcasing its versatility. The approach allows for targeted BLG growth and achieved a yield of 100% for a 10 × 10 BLG units array. Then a 10 × 10 BLG memristor array was fabricated, and a yield of 96% was achieved. The performances of these devices show good uniformity, evidenced by the set voltages concentrated around 4 V, and a high resistance state (HRS) to low resistance state (LRS) ratio predominantly around 107, reflecting the spatial uniformity of the prepared BLGA. This study provides insight into the BLG growth mechanism and opens new possibilities for BLG-based electronics.

Oxygen vacancies (VO) in metal oxide semiconductors play an important role in improving gas-sensing performance of chemiresistive gas sensors. Nonetheless, there is still a lack of clear understanding of the inherent mechanism of the influence of oxygen vacancies on gas sensing due to generally focusing on the concentration of VO. Herein, oxygen vacancies were rationally modulated in WO3nanoflower structures via an annealing process, resulting in a transformation of VOfrom neutral (VO0) to a doubly ionized (VO2+) state. Density functional theory (DFT) calculations indicate that VO2+is significantly more efficient than VO0for NO2detection in competition with atmospheric O2. Benefiting from a high concentration of VO2+, the WO3-450 (WO3annealed at 450 °C) sensor exhibits excellent sensing performance with an ultrahigh sensitivity (3674.1 to 5 ppm NO2), superior selectivity, and long-term stability (one month). Furthermore, the sensor with the wide range of concentration detection not only can detect NO2gas with parts per million (ppm) but also can detect NO2with parts per billion (ppb) level concentration, with a high sensibility reaching 2.8 to 25 ppb NO2and over 100 to 100 ppb NO2. This study elucidates the oxygen vacancy mediated sensing mechanism toward NO2and provides an effective strategy for the rational design of gas sensors with high sensing performance.

Photocatalytic reforming of ethanol provides an effective way to produce hydrogen energy using natural and nontoxic ethanol as raw material. Developing highly efficient catalysts is central to this field. Although traditional semiconductor/metal heterostructures (e.g., Rh/TiO2) can result in relatively high catalyst performance by promoting the separation of photoinduced hot carriers, it will still be highly promising to further improve the catalytic performance via a cost-effective and convenient method. In this study, we developed a highly efficient photocatalyst for ethanol reformation by preparing a ternary composite structure of Rh/TiO2/g-C3N4. Hydrogen is the main product, and the reaction rate could reach up to 27.5 mmol g–1h–1, which is ∼1.41-fold higher than that of Rh/TiO2. The catalytic performance here is highly dependent on the wavelength of the light illumination. Moreover, the photocatalytic reforming of ethanol and production of hydrogen were also dependent on the Rh loading and g-C3N4:TiO2ratio in Rh/TiO2/g-C3N4composites as well as the ethanol content in the reaction system. The mechanism of the enhanced hydrogen production in Rh/TiO2/g-C3N4is determined as the improvement in the separation of photoinduced hot carriers. This work provides an effective photocatalyst for ethanol reforming, largely expanding its application in the field of renewable energy and interface science.

Platinum(II) drugs as a first-line anticancer reagent are limited by side effects and drug resistance. Stimuli-responsive nanosystems hold promise for precise spatiotemporal manipulation of drug delivery, with the aim to promote bioavailability and minimize side effects. Herein, a multitargeting octahedral platinum(IV) prodrug with octadecyl aliphatic chain and histone deacetylase inhibitor (phenylbutyric acid, PHB) at axial positions to improve the therapeutic effect of cisplatin was loaded on the upconversion nanoparticles (UCNPs) through hydrophobic interaction. Followed attachment of DSPE-PEG2000and arginine-glycine-aspartic (RGD) peptide endowed the nanovehicles with high biocompatibility and tumor specificity. The fabricated nanoparticles (UCNP/Pt(IV)-RGD) can be triggered by upconversion luminescence (UCL) irradiation and glutathione (GSH) reduction to controllably release Pt(II) species and PHB, inducing profound cytotoxicity. Both in vitro and in vivo experiments demonstrated that UCNP/Pt(IV)-RGD exhibited remarkable antitumor efficiency, high tumor-targeting specificity, and real-time UCL imaging capacity, presenting an intelligent platinum(IV) prodrug-loaded nanovehicle for UCL-guided dual-stimuli-responsive combination therapy.

Adiabatic demagnetization refrigeration is known to be the only cryogenic refrigeration technology that can achieve ultralow temperatures (≪1 K) at gravity-free conditions. The key indexes to evaluate the performance of magnetic refrigerants are their magnetic entropy changes (−ΔSm) and magnetic ordering temperature (T0). Although, based on the factors affecting the −ΔSmof magnetic refrigerants, one has been able to judge if a magnetic refrigerant has a large −ΔSm, how to accurately predict their T0remains a huge challenge due to the fact that the T0of magnetic refrigerants is related to not only magnetic exchange but also single-ion anisotropy and magnetic dipole interaction. Here, we, taking GdCO3F (1), Gd(HCOO)F2, Gd2(SO4)3·8H2O, GdF3, Gd(HCOO)3and Gd(OH)3as examples, demonstrate that the T0of magnetic refrigerants with very weak magnetic interactions and small anisotropy can be accurately predicted by integrating mean-field approximation with quantum Monte Carlo simulations, providing an effective method for predicting the T0of ultralow-temperature magnetic refrigerants. Thus, the present work lays a solid foundation for the rational design and preparation of ultralow-temperature magnetic refrigerants in the future.

The lack of a comprehensive force field and understanding at the mesoscale for hydrated calcium silicate (CSH)/polyvinyl alcohol (PVA) fiber has hindered the upscaling and bridging of nanoscale to macroscale phenomena. In this study, we propose a coarse-grained (CG) force field that incorporates bond-breaking operations to endow fiber reactivity, abrasion, and fracture properties. By employing a cubic lattice modeling, we effectively address the challenges associated with semicrystalline relaxation of fibers. For the first time, quasi-reaction CG simulation successfully replicates slip-hardening behaviors and surface abrasion. We demonstrate that abrasion improves interface load transfer and triggers slip-hardening by redistributing stress. Additionally, the influences of single and coupled factors, such as nonbonding interactions and surface roughness, are investigated. Mesoscale understanding provides insights for enabling precise control of load transfer paths and fabrication of interface damage-predictable materials.