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Hydrazine derivatives have been extensively studied as some of the earliest reductants for Sn–Pb mixed perovskite precursors. However, phenyl hydrazine (BH) as a strong reductant for Sn-based perovskite solutions has not been reported yet, and Sn2+ is unusually oxidized in the precursor solution with BH additives in our experiment. Thus, not all organic reductants are suitable as additives, and therefore selecting a suitable reductant should be paid special attention to. Herein, it is found that BH as a Brønsted base deprotonates MA+ to produce HI, which further catalyzes the oxidation of Sn2+ by DMSO. As an alternative, hydrochloride phenyl hydrazine with a sulfonic amide group (–SO2–NH2) is added to the precursor as a reductant and passivator. As a result, a power conversion efficiency of 22.01% is achieved, and prolonged shelf stability is realized. [ABSTRACT FROM AUTHOR]

Tin‐lead (Sn‐Pb) mixed perovskite with a narrow bandgap is an ideal candidate for single‐junction solar cells approaching the Shockley‐Queisser limit. However, due to the easy oxidation of Sn2+, the efficiency and stability of Sn‐Pb mixed perovskite solar cells (PSCs) still lag far behind that of Pb‐based solar cells. Herein, highly efficient and stable FA0.5MA0.5Pb0.5Sn0.5I0.47Br0.03 compositional PSCs are achieved by introducing an appropriate amount of multifunctional Tin (II) oxalate (SnC2O4). SnC2O4 with compensative Sn2+ and reductive oxalate group C2O42− effectively passivates the cation and anion defects simultaneously, thereby leading to more n‐type perovskite films. Benefitting from the energy level alignment and the suppression of bulk nonradiative recombination, the Sn‐Pb mixed perovskite solar cell treated with SnC2O4 achieves a power conversion efficiency of 21.43%. More importantly, chemically reductive C2O42− effectively suppresses the notorious oxidation of Sn2+, leading to significant enhancement in stability. Particularly, it dramatically improves light stability. [ABSTRACT FROM AUTHOR]

To achieve large-scale development of triboelectric nanogenerators (TENGs) for water wave energy harvesting and powering the colossal sensors widely distributed in the ocean, facile and scalable TENGs with high output are urgently required. Here, an elastic self-recovering hybrid nanogenerator (ES-HNG) is proposed for water wave energy harvesting and marine environmental monitoring. The elastic skeletal support of the ES-HNG is manufactured using three-dimensional (3D) printing technology, which is more conducive to the large-scale integration of the ES-HNG. Moreover, the combination of a TENG and an electromagnetic generator (EMG) optimizes the utilization of device space, leading to enhanced energy harvesting efficiency. Experimental results demonstrate that the TENG achieves a peak power output of 42.68 mW, and the EMG reaches a peak power output of 4.40 mW. Furthermore, various marine environment monitoring sensors, such as a self-powered wireless meteorological monitoring system, a wireless alarm system, and a water quality monitoring pen, have been successfully powered by the sophisticated ES-HNG. This work introduces an ES-HNG for water wave energy harvesting, which demonstrates potential in marine environment monitoring and offers a new solution for the sustainable development of the marine internet of things. [ABSTRACT FROM AUTHOR]

Traditional eye drops are administered via topical instillation. However, frequent dosing is needed due to their relatively rapid precorneal removal and low ocular bioavailability. To address these issues, stearoyl L-carnitine-modified nanoemulsions (SC-NEs) were fabricated. The physicochemical properties of SC-NEs in terms of size, morphology, zeta potential, encapsulation efficiency, and in vitro drug release behavior were characterized. The cellular uptake and mechanisms of SC-NEs were comprehensively studied in human corneal epithelial cells and the stearoyl L-carnitine ratio in SC-NEs was optimized. The optimized SC-NEs could target the novel organic cation/carnitine transporter 2 (OCTN2) and amino acid transporter B (0 +) (ATB0,+) on the corneal epithelium, which led to superior corneal permeation, ocular surface retention ability, ocular bioavailability. Furthermore, SC-NEs showed excellent in vivo anti-inflammatory efficacy in a rabbit model of endotoxin-induced uveitis. The ocular safety test indicated that the SC-NEs were biocompatible. In general, the current study demonstrated that OCTN2 and ATB0,+-targeted nanoemulsions were promising ophthalmologic drug delivery systems that can improve ocular drug bioavailability and boost the therapeutic effects of drugs for eye diseases. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) porous heterogeneous metallic nanomaterials hold remarkable competitiveness in electrocatalytic fields due to their flexible porous structure and the electronic effect between heteroatoms, but challenges in synthesis still remain. Here, we design a facile stepwise reduction method to successfully synthesize urchin-like Au/Pd nanobranches (NBs). In a one-pot synthesis, small Au nanoparticles were initially generated. Later, numerous Pd nanotwigs were epitaxially grown and interlaced on the Au seeds to create unique channels, forming an Au-core/Pd-branches structure eventually. The as-prepared Au/Pd NBs exhibit greatly improved activity and stability for alkaline oxygen reduction reaction (ORR) electrocatalysis compared to the commercial Pt/C, with mass activity (1.4 A mg–1) and specific activity (2.4 mA cm–2) increased by 8.8 and 8.9 times, respectively. The excellent ORR performances of Au/Pd NBs are mainly attributed to the optimized electronic structure, improved utilization of surface active sites, and accelerated mass and charge transfer, which derives from the strong ligand effect, as well as the abundant porous channels of the Au/Pd NBs structure. The controllable design and synthesis of 3D porous Pd-based nanomaterials sheds light on a gigantic potential for ORR electrocatalysis. [ABSTRACT FROM AUTHOR]

The poor film stability of Sn-Pb mixed perovskite film and the mismatched interface energy levels pose significant challenges in enhancing the efficiency of tin–lead (Sn-Pb) mixed perovskite solar cells. In this study, polyvinylpyrrolidone (PVP) is introduced into the PVK perovskite precursor solution, effectively enhancing the overall stability of the film. This improvement is achieved through the formation of robust coordination bonds between the carbonyl (C=O) in the pyrrole ring and the undercoordinated SnII and PbII, thereby facilitating the passivation of defects. Furthermore, the introduction of PVP inhibits the oxidation of tin (Sn), thereby enhancing the n-type characteristics of the perovskite film. This adjustment in the energy level of the PVK perovskite film proves instrumental in reducing interface energy loss, subsequently improving interface charge transfer and mitigating device recombination. Consequently, perovskite solar cells incorporating PVP achieve an outstanding champion power conversion efficiency (PCE) of 21.31%. [ABSTRACT FROM AUTHOR]

Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi‐step catalytic reactions. Here, we report a defect‐derived strategy for creating surface phosphorous vacancies (P‐vacancies) on nanometric Rh2P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P‐terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P‐terminated Rh2P{200} facets (p‐Rh2P) can be bypassed on defective Rh2P{200} surfaces (d‐Rh2P). The P‐vacancies enable the exposure of sub‐surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P‐sites to effectively accelerate the alkaline HOR. Defective Rh2P nanowires (d‐Rh2P NWs) and perfect Rh2P nanocubes (p‐Rh2P NCs) are then elaborately synthesized to experimentally represent the d‐Rh2P and p‐Rh2P catalytic surfaces. As expected, the P‐vacancy‐enriched d‐Rh2P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p‐Rh2P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Low‐dimensional amorphous metallic nanomaterials provide great possibility for creating high‐performance electrocatalysts owing to their conspicuous reacting merits derived from the flexible coordination structures, but remain extremely challenging in synthesis. Herein, this work reports a facile synthesis of carbon‐loaded amorphous 1.5‐nm‐thick Pt–Ru nanowires (NWs) through a local oxidation induced amorphization process. During annealing premade crystalline Pt–Ru NWs/C in air, a local‐oxidation of the oxyphilic Ru generates abundant random Ru–O bonds and disturbs the order bimetallic lattices. The as‐prepared amorphous Pt53Ru47 (a‐Pt53Ru47) NWs/C exhibits an extremely high activity (13.7 A mg−1 at 25 mV overpotential) and an excellent CO‐tolerance for alkaline hydrogen oxidation reaction (HOR) electrocatalysis, drastically outperforming the crystalline counterpart and commercial benchmarks. Mechanism studies indicate the Pt–Ru bimetallic effects as well as the rich disordered "Pt–Ru–O" and/or "Pt–O–Ru" atomic heterojunctions can weaken the *H binding energy and inversely strengthen the *OH adsorption, thus promoting the alkaline HOR kinetics. More uniquely, the small interatomic spaces derived from the disordered bond nets present a H2/*H‐selected permeability, which spatially obstruct the relatively larger CO molecules to poison the internal catalytic sites during HOR. The CO‐shielded internal catalytic sites and the enriched surface *OH jointly upgrade the CO‐tolerance of the a‐Pt53Ru47 NWs/C catalysts. [ABSTRACT FROM AUTHOR]

In the recently researched Sn-contained perovskite solar cells (PSCs), limited work is focused on corrosion of a metal electrode, which is recognized as the obstacle of efficient and stable devices. Here, it is found that a pure Sn based PSC shows the most serious and quick corrosion of an Ag electrode, compared with Pb and Sn–Pb PSCs. I2, SnOX, and AgI are the main products of the aged Ag electrode in Sn based PSCs, which greatly differed from Pb and Sn–Pb PSCs. Oxidation of FASnI3 under O2/H2O produces aggressive I2, together with gaseous FA and diffusive I−, degrading the PVK film and Ag electrode greatly. This work highlights the corrosion velocity and mechanism of Ag electrodes in Sn-contained PSCs, which may help to find out possible solutions to circumvent the instable issue. [ABSTRACT FROM AUTHOR]

The development of efficient and durable hydrogen oxidation reaction (HOR) electrocatalysts is desired but challenged before the commercialization of the H2–O2 fuel cell system. In this study, ultrafine RuMo bimetallic particles (∼1.7 nm) anchored on N, P-co-doped hollow carbon polyhedrons (sub-2 nm RuMo/HC) were designed via two-step pyrolysis. For HOR in 0.1 M KOH, the sub-2 nm RuMo/HC exhibited a high-level mass activity of 3830 mA mgRu−1, nearly 25-fold and 13-fold those for commercial Ru/C and sub-2 nm Ru/HC, respectively. Such outstanding behaviour could be ascribed to the well-tuned d band structure of Ru with suitable adsorption for the H* intermediate. More importantly, the formation of soluble RuOx species on the catalyst's surface could be effectually suppressed by embedding Mo, and thus the electrochemical durability of sub-2 nm RuMo/HC was increased ∼70% during the HOR process. This work offers helpful tactics for enhancing the activity and stability in an alkaline electrooxidation system. [ABSTRACT FROM AUTHOR]

A g-C3N4/NH2-MIL-88B(Fe)/CD@GO membrane (M2) was prepared by a simple vacuum filtration method. By embedding a Z-scheme heterojunction composite photocatalyst into graphene oxide (GO) nanosheets, not only can the water molecule transport channel be regulated, but the membrane can also be endowed with photocatalytic activity and membrane fouling is effectively alleviated. The pure water permeation flux of M2 (253.26 L m−2 h−1 bar−1) was 13 times that of the original GO membrane (18.83 L m−2 h−1 bar−1). What's more, even after 10 cycles, M2 still maintains excellent separation efficiency and flux. After six cycles, the rejection of Congo Red (CR), Malachite Green (MG) and Rhodamine B (RhB) by M2 was over 95%. At the same time, under the conditions of an extreme pH value and high salt concentration, the rejection of dye remained at the original level after six cycles. Therefore, the novel photocatalytic membrane has excellent separation performance, stability and photocatalytic activity, and can be used as a potential membrane for wastewater purification and environmental protection. [ABSTRACT FROM AUTHOR]