Publications by authors named "Xiangzhong Ren"

Article Synopsis
  • Lithium metal batteries (LMBs) face challenges like dendrite growth, low cycle efficiency, and electrolyte combustion, which hinder their practical use.
  • A new electrolyte was developed by combining three types of salts in carbonate-based solvents, creating a bilayer solid electrolyte interface (SEI) that stabilizes lithium ions and suppresses dendrite formation.
  • This advanced electrolyte shows impressive performance, retaining 89.89% capacity after 200 cycles in tests, and its insights into SEI structure can help improve other battery systems as well.
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A deep understanding of the role of spin configurations of Fe-N-C catalysts in the adsorption and desorption of oxygen intermediates during ORRs is critical for the development of new catalysts for the ORR. Herein, we successfully implanted p-block metal single sites (SnN, SbN) into the Fe-N-C system to vary the spin states of Fe species and investigated the ORR performance of active metal centers with varying effective magnetic moments. Through a combination of zero-field cooling (ZFC) temperature-dependent magnetic susceptibility measurements and DFT calculations, we successfully established correlations between the spin state and ORR activity.

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Electrocatalytic water splitting is considered one of the most promising approaches for large-scale hydrogen production. However, designing transition metal catalysts with high durability under acidic conditions remains a significant challenge. The durability of the catalyst is closely related to the changes of the catalyst during its operation, and constructing effective surface reconstruction strategies can help address the durability issues of transition metals in acidic hydrogen evolution reactions (HER).

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For exploiting high-energy lithium-metal batteries, it is of utmost importance to develop electrolytes that possess exceptional ionic conductivity and an extensive electrochemical stability range. In this study, 3D PAN nanofibers and polymer electrolytes incorporating various inorganic fillers with different Lewis acid-base properties were fabricated. PAN@Al-SSE exhibits exceptional ionic conductivity (0.

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Article Synopsis
  • - Sodium-ion batteries (SIBs) show potential for advanced energy storage, but their performance is hampered by unstable cathode-electrolyte interphase (CEI), leading to capacity loss and side reactions.
  • - The study introduces a new high-concentration electrolyte combining a stable sulfolane solvent with a non-solvent, creating a thin and durable CEI that maintains stability during cycling.
  • - This improved electrolyte allows the NaNiMnFeO cathode to retain up to 81.15% of its capacity over 400 cycles, while also enhancing safety due to its nonflammable properties, offering a promising approach for future high-voltage SIB applications.
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Ni-rich single-crystalline layered cathodes have garnered significant attention due to their high energy density and thermal stability. However, they experience severe capacity degradation caused by lattice strain and interfacial side reactions during practical applications. In this study, an effective yttrium modification method is employed to stabilize the structure of Ni-rich single-crystalline LiNiMnCoO (SC-NMC83) to solve these issues.

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Article Synopsis
  • Defect engineering can help improve how nanomaterials work in electrocatalysis, but it hasn't been used much for Pt-based catalysts in oxygen reactions.
  • Researchers created a special type of nanoparticles using nickel and platinum, which showed that tiny gaps in the materials can boost their performance.
  • The combination of these tiny gaps and the nickel helps the material change quickly and work well, making it a better option for energy reactions while lasting a long time.
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Plastic-crystal-embedded elastomer electrolytes (PCEEs), produced through polymerization-induced phase separation (PIPS), are gaining popularity as solid polymer electrolytes (SPEs). However, it remains to be investigated whether all monomer molecules can achieve polymerization-induced phase separation and the corresponding differences in lithium metal battery performance. Herein, we prepared PCEEs with different functional groups (OH, CN, F) through in situ polymerization.

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The development of efficient and cost-effective electrocatalysts to overcome the intrinsic sluggish kinetics of the oxygen reduction reaction (ORR) in zinc-air batteries is crucial. In this study, we introduce a strategy that integrates a template-assisted synthesis with subsequent thermal treatment to fabricate an active and stable cobalt-based nitrogen-doped carbon electrocatalyst, denoted as Co-N-CNT. The strategy adjusts the disordered architecture of the zeolitic imidazolate framework (ZIF) through the synergistic effect of bimetallic species, restricted the growth of zeolitic imidazolate framework nanoleaves (ZIF-L) using salt templates, and directed the transformation from a two-dimensional blade-like morphology to a three-dimensional multi-tiered composite structure.

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The controllable anchoring of multiple metal single-atoms (SAs) into a single support exhibits scientific and technological opportunities, while marrying the concentration-complex multimetallic SAs and high-entropy SAs (HESAs) into one SAC system remains a substantial challenge. Here, we present a substrate-mediated SAs formation strategy to successfully fabricate a library of multimetallic SAs and HESAs on MoS and MoSe supports, which can precisely control the doping location of SAs. Specially, the contents of SAs can continuously increase until the accessible Mo atoms on TMDs carriers are completely replaced by SAs, thus allowing the of much higher metal contents.

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In this work, an advanced hybrid material was constructed by incorporating niobium pentoxide (NbO) nanocrystals with nitrogen-doped carbon (NC) derived from ZIF-8 dodecahedrons, serving as a support, referred to as NbO/NC. Pt nanocrystals were dispersed onto NbO/NC using a simple impregnation reduction method. The obtained Pt/NbO/NC electrocatalyst showed high oxygen reduction reaction (ORR) activity due to three-phase mutual contacting structure with well-dispersed Pt and NbONPs.

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Ammonium vanadate with stable bi-layered structure and superior mass-specific capacity have emerged as competitive cathode materials for aqueous rechargeable zinc-ion batteries (AZIBs). Nevertheless, fragile NH…O bonds and too strong electrostatic interaction by virtue of excessive NH will lead to sluggish Zn ion mobility, further largely affects the electro-chemical performance of ammonium vanadate in AZIBs. The present work incorporates polypyrrole (PPy) to partially replace NH in NHVO (NVO), resulting in the significantly enlarged interlayers (from 10.

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LiCoO (LCO) cathode materials have attracted significant attention for its potential to provide higher energy density in current Lithium-ion batteries (LIBs). However, the structure and performance degradation are exacerbated by increasing voltage due to the catastrophic reaction between the applied electrolyte and delithiated LCO. The present study focuses on the construction of physically and chemically robust Mg-integrated cathode-electrolyte interface (MCEI) to address this issue, by incorporating Magnesium bis(trifluoromethanesulfonyl)imide (Mg[TFSI]) as an electrolyte additive.

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Effective strategies toward building exquisite nanostructures with enhanced structural integrity and improved reaction kinetics will carry forward the practical application of alloy-based materials as anodes in batteries. Herein, a free-standing 3D carbon nanofiber (CNF) skeleton incorporated with heterostructured binary metal selenides (ZnSe/SnSe) nanoboxes is developed for Na-ion storage anodes, which can facilitate Na ion migration, improve structure integrity, and enhance the electrochemical reaction kinetics. During the carbonization and selenization process, selenium/nitrogen (Se/N) is co-doped into the 3D CNF skeleton, which can improve the conductivity and wettability of the CNF matrices.

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High energy density and high safety are incompatible with each other in a lithium battery, which challenges today's energy storage and power applications. Ni-rich layered transition metal oxides (NMCs) have been identified as the primary cathode candidate for powering next-generation electric vehicles and have been extensively studied in the last two decades, leading to the fast growth of their market share, including both polycrystalline and single-crystal NMC cathodes. Single-crystal NMCs appear to be superior to polycrystalline NMCs, especially at low Ni content (≤60%).

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The stabilization of platinum (Pt) catalysts through strong metal-support interactions is crucial for their successful implementation in fuel cell applications. Tungsten oxide (WO) has demonstrated excellent CO tolerance and has been recognized as a promising substrate for anchoring and stabilizing Pt nanoparticles (NPs). However, the limited specific surface area of conventional tungsten oxide restricts its effectiveness in dispersing noble metal NPs.

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Diabetic foot ulcers (DFUs) remain a devastating threat to human health. While hydrogels are promising systems for DFU-based wound management, their effectiveness is often hindered by the immune response and hostile wound microenvironment associated with the uncontrollable accumulation of reactive oxygen species and hypoxia. Here, we develop a therapeutic wound dressing using a biomimetic hydrogel system with the decoration of catalase-mimic nanozyme, namely, MnCoO@PDA/CPH.

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Achieving practical applications of PEO-based composite solid electrolyte (CPE) batteries requires the precise design of filler structures at the molecular level to form stable composite interfacial phases, which in turn improve the conductivity of Li and inhibit the nucleation growth of lithium dendrites. Some functional fillers suffer from severe agglomeration due to poor compatibility with the polymer base or grain boundary migration, resulting in limited improvement in cell performance. In this paper, ILs@KAP1 is reported as a filler to enhance the performance of PEO-based batteries.

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Replacing high-cost and scarce platinum (Pt) with transition metal and nitrogen co-doped carbon (M/N/C, M = Fe, Co, Mn, and so on) catalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells has largely been impeded by the unsatisfactory ORR activity of M/N/C due to the low site utilization and inferior intrinsic activity of the M─N active center. Here, these limits are overcome by using a sacrificial bimetallic pyrolysis strategy to synthesize Fe─N─C catalyst by implanting the Cd ions in the backbone of ZIF-8, leading to exposure of inaccessible FeN edge sites (that is, increasing active site density (SD)) and high fast mass transport at the catalyst layer of cathode. As a result, the final obtained Fe(Cd)─N─C catalyst has an active site density of 33.

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Azonaphthalenes have been verified as a class of effective arylation reagents in a variety of asymmetric transformations. Here a highly efficient approach to construct triaryl-substituted all-carbon quaternary stereocenters through chiral phosphoric acid-catalyzed enantioselective arylation of 3-aryl-2-oxindoles with azonaphthalenes is disclosed. This chemistry is scalable and displays excellent functional group tolerance, furnishing a series of 3,3-disubstituted 2-oxindole derivatives in good yields with excellent enantiocontrol.

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Oxygen evolution reaction (OER) is a necessary procedure in various devices including water splitting and rechargeable metal-air batteries but required a higher potential to improve oxygen evolution efficiency due to its slow reaction kinetics. In order to solve this problem, a heterostructured electrocatalyst (CoO@FeO/CC) is synthesized by deposition of iron oxides (FeO) on carbon cloth (CC) via plasma-enhanced atomic layer deposition, then growth of the cobalt oxide (CoO) nanosheet arrays. The deposition cycle of FeOon the CC strongly influences thegrowth and distribution of CoOnanosheets and electronic conductivity of the electrocatalyst.

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Rechargeable zinc-air batteries (ZABs) are a promising energy conversion device, which rely critically on electrocatalysts to accelerate their rate-determining reactions such as oxygen reduction (ORR) and oxygen evolution reactions (OER). Herein, we fabricate a range of bifunctional M-N-C (metal-nitrogen-carbon) catalysts containing M-N coordination sites and M/MC nanoparticles (M = Co, Fe, and Cu) using a new class of γ-cyclodextrin (CD) based metal-organic framework as the precursor. With the two types of active sites interacting with each other in the catalysts, the obtained Fe@C-FeNC and Co@C-CoNC display superior alkaline ORR activity in terms of low half-wave (E) potential (~ 0.

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Correction for 'Long cyclic stability of acidic aqueous zinc-ion batteries achieved by atomic layer deposition: the effect of the induced orientation growth of the Zn anode' by Zhisen Zeng , , 2021, , 12223-12232, https://doi.org/10.1039/d1nr02620h.

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Single-atom catalysts based on metal-N moieties and embedded in a graphite matrix (defined as MNC) are promising for oxygen reduction reaction (ORR). However, the performance of MNC catalysts is still far from satisfactory due to their imperfect adsorption energy to oxygen species. Herein, single-atom FeNC is leveraged as a model system and report an adjacent Ru-N moiety modulation effect to optimize the catalyst's electronic configuration and ORR performance.

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Low cycling Coulombic efficiency (CE) and messy Li dendrite growth problems have greatly hindered the development of anode-free Li-metal batteries (AFLBs). Thus, functional electrolytes for uniform lithium deposition and lithium/electrolyte side reaction suppression are desired. Here, we report a locally fluorinated electrolyte (LFE) medium layer surrounding Cu foils to tailor the chemical compositions of the solid-electrolyte interphase (SEI) in AFLBs for inhibiting the immoderate Li dendrite growth and to suppress the interfacial reaction.

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