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Combining multiple design strategies often enhances catalyst performance but usually comes with high costs and low reproducibility. A technique that enhances catalyst performance in multiple strategies is urgently needed. Herein, a novel bioregulation technique is introduced, allowing simultaneous control over morphology, particle size, doping, interface engineering, and electronic properties. Bioregulation technique utilizes the soluble extracellular polymer from Aspergillus niger as a templating agent to construct high‐performance catalysts for hydrogen and oxygen evolution reaction (HER and OER). This technique controls catalyst morphology, introduces biological N and S doping, and regulates the electronic structure of the catalyst surface. Biomolecule modification enhances surface hydrophilicity, and the nanostructure increases surface roughness and gas‐release efficiency. Theoretical calculations show that the bioregulation technique shortens the d/p‐band center, optimizing reaction intermediate adsorption and desorption. The Bio‐Pt/Co3O4 catalyst with trace Pt on the surface, designed with these strategies, achieves HER (η10 of 42 mV), OER (η10 of 221 mV), and overall water‐splitting performance (1.51 V at 10 mA cm−2), maintaining stability for over 50 h, outperforming most Pt‐based catalysts. Notably, using spent lithium‐ion battery cathodes leachate, rich in Co2⁺, successfully replicates the experiment. This approach holds promise as a mainstream method for synthesizing high‐performance materials in the future. [ABSTRACT FROM AUTHOR]

The morphology of the photoactive layer plays an important role in both the photoelectric effect and device performance of solution‐processed organic solar cells (OSCs). Optimizing the morphology requires precise control over the complex film formation kinetics, which are influenced by a range of factors from the solution state to the solid‐film state. This review delves into the in situ characterization technologies employed to understand the active layer formation process and explores strategies for controlling film formation during key stages, including solution aggregation, nucleation, crystal growth, and phase separation. Special attention is given to the mechanism by which these strategies enable real‐time morphology control during the printing process and their potential to facilitate direct printing of active layers with optimized morphology. The goal is to offer valuable insights and guidance for managing film formation kinetics in solution‐processed OSCs, ultimately addressing the challenges of real‐time morphology control in scale‐up printing and paving the way for high‐throughput production of post‐processing‐free devices. [ABSTRACT FROM AUTHOR]

Oriented microstructures are widely found in various biological systems for multiple functions. Such anisotropic structures provide low tortuosity and sufficient surface area, desirable for the design of high-performance energy storage devices. Despite significant efforts to develop supercapacitors with aligned morphology, challenges remain due to the predefined pore sizes, limited mechanical flexibility, and low mass loading. Herein, a wood-inspired flexible all-solid-state hydrogel supercapacitor is demonstrated by morphologically tuning the aligned hydrogel matrix toward high electrode-materials loading and high areal capacitance. The highly aligned matrix exhibits broad morphological tunability (47–12 µm), mechanical flexibility (0°–180° bending), and uniform polypyrrole loading up to 7 mm thick matrix. After being assembled into a solid-state supercapacitor, the areal capacitance reaches 831 mF cm−2 for the 12 µm matrix, which is 259% times of the 47 µm matrix and 403% times of nonaligned matrix. The supercapacitor also exhibits a high energy density of 73.8 µWh cm−2, power density of 4960 µW cm−2, capacitance retention of 86.5% after 1000 cycles, and bending stability of 95% after 5000 cycles. The principle to structurally design the oriented matrices for high electrode material loading opens up the possibility for advanced energy storage applications.

Recent advances in the development of organic solar cells (OSCs) have produced power conversion efficiency (PCE) of over 19%. Various studies have been conducted on scalable coating methods that are compatible with large‐area production of organic photovoltaic modules. However, it is still difficult to control the bulk heterojunction (BHJ) morphology of the active layer during large‐scale fabrication of OSCs. This study reports a morphology‐controllable strategy in OSCs using water treatment (WT) in the stirring process of the active solution, thus resulting in vortex agitation. The effects of WT and water injection volume are investigated based on three reference cells for the optimization of small‐ and large‐area devices, and the physicochemical and optical properties of the films are compared with those without WT. The thin films with WT exhibit a smoother morphology than those without WT, indicating well‐dispersed donor–acceptor phases. Therefore, enhanced efficiencies of the films are achieved via WT. Furthermore, large‐area solar cell modules with a total effective area of 10 cm2 are fabricated, and they exhibit superior PCEs as high as 11.92% (H‐NF‐DIW10), indicating that the WT method is a simple and effective strategy to fabricate large‐area organic photovoltaic modules. [ABSTRACT FROM AUTHOR]

Currently, morphology optimization methods for the fused‐ring nonfullerene acceptor‐based polymer solar cells (PSCs) empirically follow the treatments originally developed in fullerene‐based systems, being unable to meet the diverse molecular structures and strong crystallinity of the nonfullerene acceptors. Herein, a new and universal morphology controlling method is developed by applying volatilizable anthracene as solid additive. The strong crystallinity of anthracene offers the possibility to restrict the over aggregation of fused‐ring nonfullerene acceptor in the process of film formation. During the kinetic process of anthracene removal in the blend under thermal annealing, donor can imbed into the remaining space of anthracene in the acceptor matrix to form well‐developed nanoscale phase separation with bi‐continuous interpenetrating networks. Consequently, the treatment of anthracene additive enables the power conversion efficiency (PCE) of PM6:Y6‐based devices to 17.02%, which is a significant improvement with regard to the PCE of 15.60% for the reference device using conventional treatments. Moreover, this morphology controlling method exhibits general application in various active layer systems to achieve better photovoltaic performance. Particularly, a remarkable PCE of 17.51% is achieved in the ternary PTQ10:Y6:PC71BM‐based PSCs processed by anthracene additive. The morphology optimization strategy established in this work can offer unprecedented opportunities to build state‐of‐the‐art PSCs. [ABSTRACT FROM AUTHOR]

Developing novel solid additives has been regarded as a promising strategy to achieve highly efficient organic solar cells with good stability and reproducibility. Herein, a small molecule, 2,2'-(perfluoro-1,4-phenylene)dithiophene (DTBF), designed with high volatility and a strong quadrupole moment, is applied as a solid additive to implement active layer morphology control in organic solar cells. Systematic theory simulations have revealed the charge distribution of DTBF and its analog and their non-covalent interaction with the active layer materials. Benefitting from the more vital charge-quadrupole interaction, the introduction, and volatilization of DTBF effectively induced more regular and condensed molecular packing in the active layer, leading to enhanced photoelectric properties. Thus, high efficiency of over 17% is obtained in the DTBF-processed devices, which is higher than that of the control devices. Further application of DTBF in different active layer systems contributed to a deeper comprehension of this type of additive. This study highlights a facile approach to optimizing the active layer morphology by finely manipulating the quadrupole moment of volatile solid additives. [ABSTRACT FROM AUTHOR]

Ni-rich layered LiNixCoyMn1-x-yO2 (LNCM) with Ni content over >90% is considered as a promising lithium ion battery (LIB) cathode, attributed by its low cost and high practical capacity. However, Ni-rich LNCM inevitably suffers rapid capacity fading at a high state of charge due to the mechanochemical breakdown; in particular, the microcrack formation has been regarded as one of the main culprits for Ni-rich layered cathode failure. To address these issues, Ni-rich layered cathodes with a textured microstructure are developed by phosphorous and boron doping. Attributed by the textured morphology, both phosphorous- and boron-doped cathodes suppress microcrack formation and show enhanced cycle stability compared to the undoped cathode. However, there exists a meaningful capacity retention difference between the doped cathodes. By adapting the various analysis techniques, it is shown that the boron-doped Ni-rich layered cathode displays better cycle stability not only by its ability to suppress microcracks during cycling but also by its primary particle morphology that is reluctant to oxygen evolution. The present work reveals that not only restraint of particle cracks but also suppression of oxygen release by developing the oxygen stable facets is important for further improvements in state-of-the-art Li ion battery Ni-rich layered cathode materials. [ABSTRACT FROM AUTHOR]

MXenes are becoming a worthy contender for boosting the efficacy of semiconductor photocatalysts because of their rich surface and electronic properties, which is exemplified to be a dynamic yet open‐ended exploration of the materials space. Herein, the promise that MXenes hold for photocatalytic applications is elucidated by presenting the various roles of MXenes in the preparation of composite photocatalysts and enhancing their activity and stability. A specific focus is put on the key issues that should be taken into account when utilizing the specific function of MXenes and the strategies to deliver the great potential of MXenes into better play. The discussion is based on different aspects closely related to the flexible surface and electronic features of MXenes, including their morphology control, stability issue, and electronic structure mutability with the purpose to present an objective and comprehensive scenario of MXenes for photocatalysis. Finally, some noteworthy research directions for the future development of MXenes‐based photocatalytic systems are outlined and prospected. This review is expected to provide a useful scaffold for the rational design and synthesis of efficient and stable MXenes‐based photocatalysts by objectively understanding and taming the functional vitality of MXenes. [ABSTRACT FROM AUTHOR]

As one common form of gas existing in aqueous environment, gas bubbles have attracted considerable worldwide attention, owing to their promising applications in industrial production and daily life, such as pressure sensors, the recovery of valuable minerals from ores, aeration process, and water treatment. Usually, the behaviors of gas bubbles in aqueous environment are mainly dominated by buoyancy force. It drives the gas bubbles out of aqueous medium rapidly, which is unfavorable in various processes, especially in wastewater treatment. In this paper, various types of superhydrophobic poly(methyl methacrylate) (PMMA) sheets are facilely fabricated, such as five-pointed star, triangle, circular, and ellipse. Compared with other shapes of superhydrophobic PMMA sheets, the prepared superhydrophobic PMMA circular sheet is capable of efficiently adhering gas bubbles and subsequently elongating their retention time in an aqueous environment. Furthermore, superhydrophobic PMMA circular sheet arrays are prepared, which can greatly improve the degradation efficiency of methyl blue by ozone (O3). The investigations indicate that the present approach will find wild applications in bubble-related fields and provide people with inspirations to develop efficient methods to manipulate gas bubbles in aqueous environment. [ABSTRACT FROM AUTHOR]

It is generally understood that particle-shaped Li2O2 is preferred in Li-O2 batteries (LOBs) because the dominance of Li2O2 films may lead to poor electrochemical performance. The influence of Li2O2 morphology and its nucleation mechanism are probed by experiments along with the first-principle calculations. It is revealed that the LOBs with Li2O2 films deliver unexpectedly improved capacities, longer cycles, and significantly reduced overpotentials assisted by NiFeO x nanofiber catalysts. The energetically favored Li 2a vacancies under LiO2-rich conditions, small crystallites, and large contact areas with the electrode/electrolyte explain the anomalous performance enhancement. Li2O2 films are formed by a heterogeneous nucleation mechanism and the voltage applied, electrolyte, electrode surface, and use of catalysts are identified as the parameters controlling the mechanisms. The mapped correlations among these parameters shed light on the control of Li2O2 morphology for developing high-performance LOBs. [ABSTRACT FROM AUTHOR]

ZnGa2O4 and ZnGa2O4: Mn2+/Eu3+ with uniform nanosphere (diameter about 400 nm) morphology have been synthesized via a facile hydrothermal approach. XRD, Raman spectra, XPS, FT-IR, SEM, TEM, photoluminescence (PL), and cathodoluminescecne (CL) spectra are used to characterize the resulting samples. The controlled experiments indicate the dosage of trisodium citrate and pH values are responsible for shape determination of the ZnGa2O4 products. The possible fast crystallization-dissolution-recrystallization formation mechanism for these nanospheres is presented. Under UV light and low-voltage electron beam excitation, ZnGa2O4, ZnGa2O4: Mn2+ and ZnGa2O4: Eu3+ emit bright blue, green, and red luminescence, respectively. Based on density functional theory calculations from first principles, the green and red emission are caused by the Mn 3d and Eu 4f electronic structures, respectively. Besides, the dependence of the CL intensity on the calcination temperature and electrical conductivity of the samples is presented. The ZnGa2O4: Mn2+ nanospheres have a higher CL intensity than that of bulk samples under the same excitation condition. The realization of three primary colors from a single host material suggests that full color display based on ZnGa2O4 nanospheres might be achievable, showing that these materials have potential applications in lighting and display fields. [ABSTRACT FROM AUTHOR]

Hierarchical SnO2 nanoflowers, assembled from single-crystalline SnO2 nanosheets with high-index (11 $ \bar 3 $) and (10 $ \bar 2 $) facets exposed, are prepared via a hydrothermal method using sodium fluoride as the morphology controlling agent. Formation of the 3D hierarchical architecture comprising of SnO2 nanosheets takes place via Ostwald ripening mechanism, with the growth orientation regulated by the adsorbate fluorine species. The use of Sn(II) precursor results in simultaneous Sn2+ self-doping of SnO2 nanoflowers with tunable oxygen vacancy bandgap states. The latter further results in the shifting of semiconductor Fermi levels and extended absorption in the visible spectral range. With increased density of states of Sn2+-doped SnO2 selective facets, this gives rise to enhanced interfacial charge transfer, that is, high sensing response, and selectivity towards oxidizing NO2 gas. The better gas sensing performance over (10 $ \bar 2 $) compared to (11 $ \bar 3 $) faceted SnO2 nanostructures is elucidated by surface energetic calculations and Bader analyses. This work highlights the possibility of simultaneous engineering of surface energetics and electronic properties of SnO2 based materials. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) are a class of semiconductive porous materials, showing enormous potential in many applications, such as gas adsorption and storage, and heterogeneous catalysis. At present, most of the studies on CTFs are focused on the structural design, synthesis, and applications, whereas very little attention is paid to morphological study, probably due to the difficulty in the control of the morphology via the conventional synthetic methods. In this work, a general approach is reported to fabricate morphological controllable CTFs by virtue of a mild polycondensation reaction via template method. As a proof of concept, a new type of hollow‐structured CTFs is developed for the first time. The shell thickness of the hollow CTFs can be conveniently tuned by varying the amount of the template. Notably, the morphologies can be transformed from sphere to bowl with the decrease of the shell thicknesses. The hollow morphology of CTFs can efficiently improve the photocatalytic hydrogen evolution performance, in which the hydrogen evolution rate can be boosted by about 4 times as compared to the bulk state. The present study not only shows an effective strategy to construct morphology controllable CTFs, but also demonstrates an effective way to enhance photocatalytic performance for CTFs. [ABSTRACT FROM AUTHOR]

In article number 1800846, Hiroshi Yabu, Guillaume Delaittre, and co‐workers propose a simple procedure to prepare nanoparticles with surface‐expressed reactive patches and corresponding nanodiscs by a nanoprecipitation technique with functional block copolymers. The surface pattern formation is controlled by the preparation conditions. Spatially confined functionalization is demonstrated by grafting model thiol compounds. These nanomaterials are structurally approaching biological particles and are interesting building blocks for colloidal assemblies. [ABSTRACT FROM AUTHOR]

Nanoparticles with structural or chemical anisotropy are promising materials in domains as diverse as cellular delivery, photonic materials, or interfacial engineering. The surface chemistry may play a major role in some of these contexts. Introducing reactivity into such polymeric nanomaterials is thus of great potential, yet is still a concept in its infancy. In the current contribution, a simple nanoprecipitation technique leads to nanoparticles with diameters as low as 150 nm and well‐defined reactive surface patches of less than 30 nm in width, as well as surface‐reactive flat, disc‐like nanoparticles with corresponding dimensions, via an additional crosslinking/delamination sequence. To this aim, chemically doped block copolymers (BCPs) are employed. Control over morphology is attained by tuning preparation conditions, such as polymer concentration, solvent mixture composition, and blending with non‐functional BCP. Surface reactivity is demonstrated using a modular ligation method for the site‐selective immobilization of thiol molecules. The current approach constitutes a straightforward methodology requiring minimal engineering to produce nanoparticles with confined surface reactivity and/or shape anisotropy. Nanoparticles with surface‐expressed reactive patches and corresponding nanodiscs are prepared by a simple nanoprecipitation technique with functional block copolymers. The surface pattern formation is controlled by preparation conditions (concentration, solvent, and functionality). Spatially confined functionalization is demonstrated by grafting model thiol compounds. These nanomaterials are structurally approaching biological particles and are interesting building blocks for colloidal assemblies. [ABSTRACT FROM AUTHOR]