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Item Open Access ESRP1 controls biogenesis and function of a large abundant multiexon circRNA(Oxford University Press, 2024) Liu, D.; Dredge, B.K.; Bert, A.G.; Pillman, K.A.; Toubia, J.; Guo, W.; Dyakov, B.J.A.; Migault, M.M.; Conn, V.M.; Conn, S.J.; Gregory, P.A.; Gingras, A.-C.; Patel, D.; Wu, B.; Goodall, G.J.While the majority of circRNAs are formed from infrequent back-splicing of exons from protein coding genes, some can be produced at quite high level and in a regulated manner. We describe the regulation, biogenesis and function of circDOCK1(2-27), a large, abundant circular RNA that is highly regulated during epithelial-mesenchymal transition (EMT) and whose formation depends on the epithelial splicing regulator ESRP1. CircDOCK1(2-27) synthesis in epithelial cells represses cell motility both by diverting transcripts from DOCK1 mRNA production to circRNA formation and by direct inhibition of migration by the circRNA. HITS-CLIP analysis and CRISPR-mediated deletions indicate ESRP1 controls circDOCK1(2-27) biosynthesis by binding a GGU-containing repeat region in intron 1 and detaining its splicing until Pol II completes its 157 kb journey to exon 27. Proximity-dependent biotinylation (BioID) assay suggests ESRP1 may modify the RNP landscape of intron 1 in a way that disfavours communication of exon 1 with exon 2, rather than physically bridging exon 2 to exon 27. The X-ray crystal structure of RNA-bound ESRP1 qRRM2 domain reveals it binds to GGU motifs, with the guanines embedded in clamp-like aromatic pockets in the protein.Item Metadata only High-Power CO₂‑to‑C₂ Electroreduction on Ga-Spaced, Square-like Cu Sites(American Chemical Society (ACS), 2023) Yan, S.; Chen, Z.; Chen, Y.; Peng, C.; Ma, X.; Lv, X.; Qiu, Z.; Yang, Y.; Yang, Y.; Kuang, M.; Xu, X.; Zheng, G.The electrochemical conversion of CO2 into multicarbon (C2) products on Cu-based catalysts is strongly affected by the surface coverage of adsorbed CO (*CO) intermediates and the subsequent C−C coupling. However, the increased *CO coverage inevitably leads to strong *CO repulsion and a reduced C−C coupling efficiency, thus resulting in suboptimal CO2-to-C2 activity and selectivity, especially at ampere-level electrolysis current densities. Herein, we developed an atomically ordered Cu9Ga4 intermetallic compound consisting of Cu square-like binding sites interspaced by catalytically inert Ga atoms. Compared to Cu(100) previously known with a high C2 selectivity, the Ga-spaced, square-like Cu sites presented an elongated Cu−Cu distance that allowed to reduce *CO repulsion and increased *CO coverage simultaneously, thus endowing more efficient C−C coupling to C2 products than Cu(100) and Cu(111). The Cu9Ga4 catalyst exhibited an outstanding CO2-to-C2 electroreduction, with a peak C2 partial current density of 1207 mA cm−2 and a corresponding Faradaic efficiency of 71%. Moreover, the Cu9Ga4 catalyst demonstrated a high-power (∼200 W) electrolysis capability with excellent electrochemical stability.Item Open Access Mitigating stimulated Brillouin scattering in multimode fibers with focused output via wavefront shaping(Nature Portfolio, 2023) Chen, C.-W.; Nguyen, L.V.; Wisal, K.; Wei, S.; Warren-Smith, S.C.; Henderson-Sapir, O.; Schartner, E.P.; Ahmadi, P.; Ebendorff-Heidepriem, H.; Stone, A.D.; Ottaway, D.J.; Cao, H.The key challenge for high-power delivery through optical fibers is overcoming nonlinear optical effects. To keep a smooth output beam, most techniques for mitigating optical nonlinearities are restricted to single-mode fibers. Moving out of the single-mode paradigm, we show experimentally that wavefront-shaping of coherent input light to a highly multimode fiber can increase the power threshold for stimulated Brillouin scattering (SBS) by an order of magnitude, whilst simultaneously controlling the output beam profile. The SBS suppression results from an effective broadening of the Brillouin spectrum under multimode excitation, without broadening of transmitted light. Strongest suppression is achieved with selective mode excitation that gives the broadest Brillouin spectrum. Our method is efficient, robust, and applicable to continuous waves and pulses. This work points toward a promising route for mitigating detrimental nonlinear effects in optical fibers, enabling further power scaling of high-power fiber systems for applications to directed energy, remote sensing, and gravitational-wave detection.Item Metadata only Recent progress and perspectives on dual-ion batteries(Elsevier BV, 2019) Hao, J.; Li, X.; Song, X.; Guo, Z.Lithium-ion batteries (LIBs) have gradually approached the upper limit of capacity, and yet, they are still far from fulfilling the ambitious targets required to meet the grid’s storage needs due to their unsatisfactory cycling stability, limited energy density, high cost, and environmental concerns. Dual-ion batteries (DIBs) with non-aqueous electrolyte, as potential alternatives to LIBs in smart-grid application, have attracted much attention in recent years. DIBs were initially known as dual-graphite batteries, where both anions and cations separately intercalate into graphite electrodes during the charge-discharge process. The anion intercalation into the hostmaterial enables DIBsin non-aqueous electrolyte to feature a high operating voltage,which also contributes to their enhanced energy density. Moreover, the use of low-cost and “green” raw electrode materials in DIBs offers huge advantages compared to LIBs, in terms of environmental protection by avoiding problems from the disposal of discarded batteries. In this contribution, we comprehensively summarize the recent progress on DIBs with aqueous and non-aqueous electrolytes as well as the limitations and challenges of current DIB technology. Furthermore, some suggestions that might help to address the current challenges of DIB technology are proposed for future work.Item Open Access Recent progress in electrolyte design for advanced lithium metal batteries(Wiley, 2023) Li, M.; Wang, C.; Davey, K.; Li, J.; Li, G.; Zhang, S.; Mao, J.; Guo, Z.Lithium metal batteries (LMBs) have attracted considerable interest for use in electric vehicles and as next-generation energy storage devices because of their high energy density. However, a significant practical drawback with LMBs is the instability of the Li metal/electrolyte interface, with concurrent parasitic reactions and dendrite growth, that leads to low Coulombic efficiency and poor cycle life. Owing to the significant role of electrolytes in batteries, rationally designed electrolytes can improve the electrochemical performance of LMBs and possibly achieve fast charge and a wide range of working temperatures to meet various requirements of the market in the future. Although there are some review papers about electrolytes for LMBs, the focus has been on a single parameter or single performance separately and, therefore, not sufficient for the design of electrolytes for advanced LMBs for a wide range of working environments. This review presents a systematic summary of recent progress made in terms of electrolytes, covering the fundamental understanding of the mechanism, scientific challenges, and strategies to address drawbacks of electrolytes for high-performance LMBs. The advantages and disadvantages of various electrolyte strategies are also analyzed, yielding suggestions for optimum properties of electrolytes for advanced LMBs applications. Finally, the most promising research directions for electrolytes are discussed briefly.Item Metadata only Rechargeable zinc-air batteries with neutral electrolytes: Recent advances, challenges, and prospects(Elsevier BV, 2021) Wang, C.; Li, J.; Zhou, Z.; Pan, Y.; Yu, Z.; Pei, Z.; Zhao, S.; Wei, L.; Chen, Y.Rechargeable zinc-air batteries (R-ZABs) are attractive for many essential energy storage applications – from portable electronics, electric vehicles to incorporation of renewable energy due to their high energy storage density, abundant raw materials, and inherent safety. However, alkaline electrolytes cause critical obstacles in realizing a long battery life. Thus, neutral electrolytes are attracting growing interest. However, the current understandings of R-ZABs in neutral/near-neutral electrolytes are far behind those in alkaline electrolytes. This review summarizes the latest research progress of neutral electrolytes used in R-ZABs, including aqueous inorganic and organic salt solutions, water-in-salt electrolytes, and quasi-solid electrolytes based on polymer hydrogels. Research efforts in improving the stability of Zn anodes in neutral electrolytes are also reviewed. Reaction mechanisms of oxygen reduction and evolution reactions in alkaline and neutral electrolytes are compared in the context of R-ZABs, together with a summary of potential oxygen electrocatalysts applicable in neutral conditions. Different device configurations are introduced. We further provide our perspectives on future research directions of R-ZABs with neutral electrolytes.Item Metadata only Tailoring the CO and H Coverage for Selective CO₂ Electroreduction to CH₄ or C₂H₄(Wiley-VCH GmbH, 2024) Chen, Y.; Lyu, N.; Zhang, J.; Yan, S.; Peng, C.; Yang, C.; Lv, X.; Hu, C.; Kuang, M.; Zheng, G.In the electrochemical CO2 reduction reaction (CO2RR), the coverages of *CO and *H intermediates on a catalyst surface are critical for the selective generation of C1 or C2 products. In this work, we have synthesized several CuxZnyMnz ternary alloy electrocatalysts, including Cu8ZnMn, Cu8Zn6Mn, and Cu8ZnMn2, by varying the doping compositions of Zn and Mn, which are efficient in binding *CO and *H adsorbates in the CO2 electroreduction process, respectively. The increase of *H coverage allows to promotion of the CH4 and H2 formation, while the increase of the *CO coverage facilitates the production of C2H4 and CO. As a result, the Cu8ZnMn catalyst presented a high CO2-to-CH4 partial current density (−418 ± 22 mA cm−2) with a Faradaic efficiency of 55 ± 2.8%, while the Cu8Zn6Mn catalyst exhibited a CO2-to-C2H4 partial current density (−440 ± 41 mA cm−2) with a Faradaic efficiency of 58 ± 4.5%. The study suggests a useful strategy for rational design and fabrication of Cu electrocatalysts with different doping for tailoring the reduction products.Item Metadata only Cu₇S₄/MxSy (M=Cd, Ni, and Mn) Janus Atomic Junctions for Plasmonic Energy Upconversion Boosted Multi-Functional Photocatalysis(Wiley, 2023) Guo, M.; Talebian-Kiakalaieh, A.; Xia, B.; Hu, Y.; Chen, H.; Ran, J.; Qiao, S.Z.Rational design/synthesis of atomic-level-engineered Janus junctions for sunlight-impelled high-performance photocatalytic generation of clean fuels (e.g., H2O2 and H2) and valuable chemicals are of great significance. Especially, it is appealing but challenging to acquire accurately-engineered Janus atomic junctions (JAJs) for simultaneously realizing the plasmonic energy upconversion with near-infrared (NIR) light and direct Z-scheme charge transfer with visible light. Here, a range of new Cu7S4/MxSy (M=Cd, Ni, and Mn) JAJs are designed/synthesized via a cation-exchange route using Cu7S4 hexagonal nanodisks as templates. All Cu7S4/MxSy JAJs show apparently-enhanced photocatalytic H2O2 evolution compared to Cu7S4 in pure water. Notably, optimized Cu7S4/CdS (CCS) JAJ exhibits the outstanding H2O2 evolution rate (2.93 mmol g−1 h−1) in benzyl alcohol aqueous solution, due to the following factors: i) NIR light-impelled plasmonic energy upconversion induced H2O2 evolution, revealed by ultrafast transient absorption spectroscopy; ii) visible-light-driven direct Z-scheme charge migration, confirmed by in situ X-ray photoelectron spectroscopy. Besides, three different reaction pathways for H2O2 evolution are disclosed by in situ electron spin resonance spectroscopy and quenching experiments. Finally, CCS JAJ also exhibits super-high rates on H2 and benzaldehyde co-generation using visible-NIR light or NIR light. This work highlights the significance of atomic-scale interface engineering for solar-to-chemical conversion.Item Open Access Characterisation of the heme aqua-ligand coordination environment in an engineered peroxygenase cytochrome P450 variant(Elsevier, 2023) Podgorski, M.N.; Lee, J.H.Z.; Harbort, J.S.; Nguyen, G.T.H.; Doherty, D.Z.; Donald, W.A.; Harmer, J.R.; Bruning, J.B.; Bell, S.G.The cytochrome P450 enzymes (CYPs) are heme-thiolate monooxygenases that catalyse the insertion of an oxygen atom into the C–H bonds of organic molecules. In most CYPs, the activation of dioxygen by the heme is aided by an acid-alcohol pair of residues located in the I-helix of the enzyme. Mutation of the threonine residue of this acid-alcohol pair of CYP199A4, from the bacterium Rhodospeudomonas palustris HaA2, to a glutamate residue induces peroxygenase activity. In the X-ray crystal structures of this variant an interaction of the glutamate side chain and the distal aqua ligand of the heme was observed and this results in this ligand not being readily displaced in the peroxygenase mutant on the addition of substrate. Here we use a range of bulky hydrophobic and nitrogen donor containing ligands in an attempt to displace the distal aqua ligand of the T252E mutant of CYP199A4. Ligand binding was assessed by UV–visible absorbance spectroscopy, native mass spectrometry, electron paramagnetic resonance and X-ray crystallography. None of the ligands tested, even the nitrogen donor ligands which bind directly to the iron in the wild-type enzyme, resulted in displacement of the aqua ligand. Therefore, modification of the I-helix threonine residue to a glutamate residue results in a significant strengthening of the ferric distal aqua ligand. This ligand was not displaced using any of the ligands during this study and this provides a rationale as to why this mutant can shutdown the monooxygenase pathway of this enzyme and switch to peroxygenase activity.Item Open Access Atomic-Scale Defected HfS₂ Nanosheets: A Novel Platform Enhancing Photocatalysis(Wiley, 2023) Talebian-Kiakalaieh, A.; Hashem, E.M.; Guo, M.; Xia, B.; Ran, J.; Qiao, S.Z.Recently, novel 2D materials with fascinating characteristics are extensively applied to design/fabricate high-activity and cost-effective photocatalysts for solar-driven fuels/chemicals generation. Among these 2D materials, HfS2 nanosheets (NSs) exhibit excellent features of large surface area, short bulk-to-surface distance, alterable band structures, and vast catalytic sites. Despite these features, no realistic experimental works on HfS2-based materials are reported in photocatalysis field. Moreover, it is interesting but challenging to realize atomic-scale engineering of compositions/structures for novel 2D materials and to relate these atomic-scale characteristics with the element/space/time-resolved charge kinetics of 2D materials-based photocatalysts. Herein, for the first time, atomic-scale defected HfS2 NSs are designed/synthesized. The as-synthesized HfS2 NSs are combined with various photocatalysts to acquire novel HfS2-TiO2, HfS2-CdS, HfS2-ZnIn2S4, and HfS2-C3N4 composites, respectively. Among them, HfS2-CdS exhibits the highest rate (5971 μmol g−1 h−1) on hydrogen (H2) evolution in triethanolamine aqueous solution, together with obviously-enhanced rates on H2 (2419 μmol g−1 h−1) and benzaldehyde (5.11 mmol g−1 h−1) evolution in benzyl alcohol aqueous solution. Various state-of-art characterizations reveal the element/space/time-resolved electron/hole kinetics in HfS2-CdS composites, disclosing that these atomic-scale S vacancies temporarily trapping electrons to facilitate spatiotemporal electron–hole separation/transfer. This work paves avenues to atomic-scale design/synthesis of new 2D-materials-based photocatalysts for sunlight utilization.Item Open Access Res2 Nanosheets with In Situ Formed Sulfur Vacancies for Efficient and Highly Selective Photocatalytic CO2 Reduction(Wiley, 2021) Zhang, Y.; Yao, D.; Xia, B.; Xu, H.; Tang, Y.; Davey, K.; Ran, J.; Qiao, S.-Z.Artificial photosynthesis can provide valuable fuels and positively impact greenhouse effects, via transforming carbon dioxide (CO2) and water (H2O) into hydrocarbons using semiconductor-based photocatalysts. However, the inefficient charge-carrier dissociation and transportation as well as the lack of surface active sites are two major drawbacks to boosting their activity and selectivity in photocatalytic CO2 reduction. Recently, ReS2 has received tremendous attention in the photocatalysis area due to its intriguing physicochemical properties. Nevertheless, the application of ReS2 in photocatalytic CO2 reduction is scarcely covered. Herein, a heterojunction formed between ReS2 nanosheets and CdS nanoparticles is reported, achieving an apparently raised CO production of 7.1 μmol g 1 and high selectivity of 93.4%. The as-prepared ReS2/CdS heterojunction exhibits strengthened visible-light absorption, high-efficiency electron– hole pair separation/transfer, and increased adsorption/activation/reduction of CO2 on in situ created sulfur vacancies of ReS2, thus all favoring CO2 photoreduction. These are corroborated by advanced characterization techniques, e.g., synchrotron-based X-ray absorption near-edge structure, and density functional theory–based computations. The findings will be of broad interest in practical design and fabrication of surface active sites and semiconductor heterojunctions for applications in catalysis, electronics, and optoelectronics.Item Open Access Scaling up capacity of stand-alone adsorption refrigeration tubes(Elsevier, 2019) Chen, E.; Wu, X.; Zhao, Y.; Hu, E.; Torres, J.F.On the basis of a validated model, a parametric study is conducted to understand the effects of operating parameters on the coefficient of performance (COP) and specific cooling power (SCP) of a stand-alone adsorption refrigeration tube (ART). It is revealed that the SCP obtained based on the model with the transient pressure process (TPP) boundary condition is approximately 20% higher than that obtained without the TPP. A scaling up solution of using multiple ARTs to produce continuous cooling is also proposed and discussed.Item Metadata only Challenges in radical/nonradical-based advanced oxidation processes for carbon recycling(Cell Press (Elsevier), 2022) Yang, Y.; Ren, W.; Hu, K.; Zhang, P.; Wang, Y.; Duan, X.; Sun, H.; Wang, S.Advanced oxidation processes (AOPs) have been extensively investigated on catalytic degradation of organics to carbon dioxide as well as synthesis of macromolecules via free radical-initiated polymerization (RP-AOPs). More recently, nonradical oxidation pathways have been reported in AOPs, which can also trigger polymerization (NRP-AOPs) with high selectivity due to the mild oxidative potential and favorable reaction pathways. In this perspective, we present the advances in RP/NRP-AOPs for innovative polymer manufacture for carbon recycling and classify the polymerization of various monomer compounds, including phenolic, aniline, thiophene, and vinyl monomers. The origins and pathways of polymerization reactions are discussed. We particularly highlight the recent discoveries of NRP-AOPs and the reaction parameters of RP/NRPAOPs to synthesize various value-added polymers in water, featured by an easy-to-handle system with mild reaction conditions and low chemical input, providing instructional strategies to prepare the value-added polymers from organicwastes tominimize carbon footprint and achieve a circular economy.Item Open Access Cation Inversion in Slag Magnetite: Energy Loss Measurements of Fe-L₃ Edge Shift between Atom Columns(Elsevier, 2023) Gezzaz, H.; Ciobanu, C.L.; Slattery, A.; Cook, N.J.; Ehrig, K.Determination of cation disorder in inverse spinels like magnetite, Fe3O4, is of broad interest for applications in green technologies, storage devices, and nuclear waste management since cation distributions govern magnetic and electrical properties. Magnetite is a main component of slags produced by smelting of copper ores and contains potentially valuable trace elements. We address cation disorder as a factor controlling the behavior of these elements during atmospheric cooling from 1300 °C. To estimate cation disorder, we combine atomic-scale scanning transmission electron microscopy with electron energy loss spectroscopy. The inversion parameter (0.72) indicates minor partial ordering due to fast cooling from high temperature, resulting in skeletal textures. Trace element incorporation into magnetite, instead of exsolution of discrete nanoparticle phases is promoted. Our findings provide insights into the cooling behavior of spinels and facilitate robust thermodynamic modeling that addresses the stability of structures during cooling from melts. Findings carry implications for critical element recovery and prospects for transforming industrial waste into future resources.Item Open Access C₆₀ and Derivatives Boost Electrocatalysis and Photocatalysis: Electron Buffers to Heterojunctions(Wiley-VCH, 2023) Xu, Z.; Wang, Y.; Li, Y.; Wang, Y.; Peng, B.; Davey, K.; Sun, L.; Li, G.; Zhang, S.; Guo, Z.Buckminsterfullerene (C₆₀) and derivatives are significant in the synthesis of efficient electrocatalysts and photocatalysts. This is because of electron acceptor properties and distinctive heterostructure(s) and physicochemical characteristics. High-performance electrocatalysts and photocatalysts are important therefore in conversions for clean energy. Here a critical assessment of advances in use of C₆₀ and derivatives as heterostructures and “electron buffers” in catalysts are reported. Methodologies for preparing C₆₀ composite catalysts are assessed and categorized and microscopic mechanisms for boosting catalytic performance through C₆₀ and derivatives in important catalytic materials including, semiconductors, carbon-based metal-free materials, metal nanoclusters, single atoms, and metal–organic skeletons are established. Important characterizations used with C₆₀ and derivative composites are contrasted and assessed and practical challenges to development are determined. A prospective on future directions and likely outcomes in development of high efficiency electrocatalysts and photocatalysts is provided. It is concluded that C₆₀ and derivatives are advantageous for advanced electrocatalysts and photocatalysts with high structural integrity and boosted electron transport. The findings are expected to be of interest and benefit to researchers and manufacturers for formation of heterostructures and electron buffer areas for significantly boosted catalytic performance.Item Open Access Single atom catalysts for heterogeneous catalytic ozonation(Elsevier BV, 2023) Cheng, Y.; Chen, Z.; Wang, S.; Duan, X.Single atom catalysts (SACs) have received soaring interest in environmental applications due to their ultrahigh atomic efficiency and drastically reduced metal loading. In this review, we summarized the preliminary efforts in applying SACs for heterogeneous catalytic ozonation (HCO). Mechanistic analyses revealed a creditable consensus that highly dispersed active single atoms can accelerate the decomposition of ozone (O3) into surface-adsorbed *O and free O2. However, the activity of SAC toward O3 decomposition varies, depending on the central metal species and coordination environment. In this review, we discussed the synthesis and characterization of SACs, emphasizing their application and catalytic regimes in HCO. Also, limitations and prospects of SAC-based HCO were proposed to shed light on future studies.Item Open Access Boosting urea electrooxidation on oxyanion-engineered nickel sites via inhibited water oxidation(Springer Nature, 2023) Gao, X.; Bai, X.; Wang, P.; Jiao, Y.; Davey, K.; Zheng, Y.; Qiao, S.-Z.Renewable energy-based electrocatalytic oxidation of organic nucleophiles (e.g.methanol, urea, and amine) are more thermodynamically favourable and, economically attractive to replace conventional pure water electrooxidation in electrolyser to produce hydrogen. However, it is challenging due to the competitive oxygen evolution reaction under a high current density (e.g., >300 mA cm-2), which reduces the anode electrocatalyst's activity and stability. Herein, taking lower energy cost urea electrooxidation reaction as the model reaction, we developed oxyanion-engineered Nickel catalysts to inhibit competing oxygen evolution reaction during urea oxidation reaction, achieving an ultrahigh 323.4 mA cm-2 current density at 1.65 V with 99.3 ± 0.4% selectivity of N-products. In situ spectra studies reveal that such in situ generated oxyanions not only inhibit OH- adsorption and guarantee high coverage of urea reactant on active sites to avoid oxygen evolution reaction, but also accelerate urea's C - N bond cleavage to form CNO - intermediates for facilitating urea oxidation reaction. Accordingly, a comprehensive mechanism for competitive adsorption behaviour between OH- and urea to boost urea electrooxidation and dynamic change of Ni active sites during urea oxidation reaction was proposed. This work presents a feasible route for high-efficiency urea electrooxidation reaction and even various electrooxidation reactions in practical applications.Item Metadata only Biocompatible snowman-like tumor-targeting dimer nanoparticles for improved delivery efficiency and enhanced anti-tumor therapy(Elsevier BV, 2023) Ye, C.; Yan, X.; Dai, X.; Chen, R.; Li, Q.; Xu, S.; Jiang, Q.; Yan, F.; Xu, S.; Zhao, C.X.; Zhao, P.; Chen, D.; Ruan, J.Chemotherapy is indispensable for the systematic treatment of aggressive malignancies, such as pancreatic ductal adenocarcinoma (PDAC), while delivery vehicles are essential for improving delivery efficiency and enhancing anti-tumor therapy. Here, we design and synthesize snowman-like tumor-targeting PLA/shellac-FA dimer nanoparticles (NPs), which demonstrate improved delivery efficiency and enhanced anti-tumor therapy. Paclitaxel (PTX) and curcumin (CUR) are co-loaded in PLA/shellac-FA dimer NPs and their delivery performance is optimized by tuning the particle shape to be snowman-like. In vivo tests confirm that PTX + CUR-loaded snowman-like PLA/shellac-FA dimer NPs could effectively reduce the proportion of tumor-associated macrophages (TAMs) in lymphocytes and reshape the M1/M2 polarization into an anti-tumor type. Meanwhile, the dimer NPs could enhance the infiltration of cytotoxic T lymphocytes (CTLs), thus activating the immune response in the tumor microenvironment (TME). The results suggest that snowman-like PLA/shellac-FA dimer NPs with a sharp shape can effectively improve the delivery efficiency and enhance the anti-tumor therapy, being a promising system for clinical applications.Item Open Access Spatial Structure Engineering of Interactive Single Platinum Sites toward Enhanced Electrocatalytic Hydrogen Evolution(Wiley, 2023) Ye, C.; Shan, J.; Zhu, C.; Xu, W.; Song, L.; Zhu, Y.; Zheng, Y.; Qiao, S.Z.Regulating site-to-site interactions between active sites can effectively tailor the electrocatalytic behavior of single-atom catalysts (SACs). The conventional SACs suffer from low density of single atoms and lack of site-to-site interactions between them. Herein, a series of interactive Pt SACs with controllable Pt–Pt spatial correlation degree and local coordination environment is developed by integrating densely populated Pt single atoms in the sub-lattice of a Co3O4 matrix. The obtained interactive Pt-Co3O4 catalysts demonstrate remarkable electrocatalytic performance toward hydrogen production, outperforming those of isolated single atom- and nanoparticle-based catalysts. The intrinsic catalytic activity of interactive Pt-Co3O4 catalysts is closely dependent on the spatial structure of Pt sites with the adjusted d-band center by regulating contents and atomic configuration of Pt sites. This work provides fundamental insights for the structure-property relationship on interactive single active sites, which is expected to direct the rational design of highly efficient SACs.Item Open Access Tandem internal electric fields in intralayer/interlayer carbon nitride homojunction with a directed flow of photo-excited electrons for photocatalysis(Elsevier BV, 2023) Zhang, J.; Tan, X.; Shi, L.; Chen, H.; Liu, Y.; Wang, S.; Duan, X.; Wu, M.; Sun, H.; Wang, S.Photocatalytic hydrogen production is a green technology while significantly impeded by the sluggish and uncontrolled charge dynamics for less electron accumulation on catalyst surface. Herein, we proposed an effective strategy of epitaxial growth of a van der Waals (VDW) homojunction on an intralayer homojunction of carbon nitride for a controlled charge flow. Experimental and simulation collectively disclosed a tandem internal electric field (IEF) in the integrated hybrid, stringing a lateral IEF along the intralayer homojunction with a vertical IEF within the VDW homojunction. The planar IEF dominates laterally dispersive movement of charge carriers for their efficient separations and mobilities, meanwhile the vertical IEF induces an oriented accumulation of the dispersive hot electrons to the catalyst surface for intensified hydrogen reduction. The tandem IEF renders the hydrogen evolution rate at 3.5-fold higher than in-planar homojunction, and 6.3 times higher than g-C3N4 benchmark. This work realizes charge-directing dynamics for robust photocatalysis.