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Impact electrochemistry allows for the investigation of the properties of single entities, ranging from nanoparticles (NPs) to soft bio-particles. It has introduced a novel dimension in the field of biological analysis, enhancing researchers' ability to comprehend biological heterogeneity and offering a new avenue for developing novel diagnostic devices for quantifying biological analytes. This review aims to summarize the recent advancements in impact electrochemistry-based biosensing over the past two to three years and provide insights into the future directions of this field. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) has emerged as a promising cathode material in aqueous batteries. It possesses two distinct redox centers, and the potassium ions (K+) are unevenly distributed throughout the compound, adding complexity to the interpretation of the K+ insertion/de‐insertion kinetic mechanism. Traditional ensemble‐averaged measurements are limited in uncovering the precise kinetic information of the PB particles, as the results are influenced by the construction of the porous composite electrode and the redox behavior from different particles. In this study, the electrochemical processes of individual PB particles were investigated using nano‐impact electrochemistry. By varying the potentials, different types of transient current signals were obtained that revealed the kinetic mechanism of each oxidation/reduction reaction in combination with theoretical simulation. Additionally, a partially contradictory conclusion between single‐particle analysis and the ensemble‐averaged measurement was discussed. These findings contribute to a better understanding of the electrochemical processes of cathode materials with multiple redox centers, which facilitates the development of effective strategies to optimize these materials. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) has emerged as a promising cathode material in aqueous batteries. It possesses two distinct redox centers, and the potassium ions (K+) are unevenly distributed throughout the compound, adding complexity to the interpretation of the K+ insertion/de‐insertion kinetic mechanism. Traditional ensemble‐averaged measurements are limited in uncovering the precise kinetic information of the PB particles, as the results are influenced by the construction of the porous composite electrode and the redox behavior from different particles. In this study, the electrochemical processes of individual PB particles were investigated using nano‐impact electrochemistry. By varying the potentials, different types of transient current signals were obtained that revealed the kinetic mechanism of each oxidation/reduction reaction in combination with theoretical simulation. Additionally, a partially contradictory conclusion between single‐particle analysis and the ensemble‐averaged measurement was discussed. These findings contribute to a better understanding of the electrochemical processes of cathode materials with multiple redox centers, which facilitates the development of effective strategies to optimize these materials. [ABSTRACT FROM AUTHOR]

Appropriate materials collaborated with reasonable structure can significantly increase the separator performance for lithium-ion batteries. In this work, taking the advantages of microfibrous and nanofibrous membranes and compensating for their defects, we developed a composited separator (GOPPH) with excellent overall performance by first wetting-modifying the polyethylene terephthalate microfibers and then laminating a polyvinylidene fluoride-hexafluoropropylene nanofiber layer. Such a combination not only offers the GOPPH separator, from the perspective of structure, with high porosity and hierarchical structure in terms of fiber diameter and pore size, but also provides satisfactory features including wettability, mechanical strength and thermal shutdown function that benefit from the selected materials. Meanwhile, as determined by experimental and theoretical approaches, the obtained GOPPH separator exhibits considerably enhanced lithium ion transport ability with a high lithium ion transference number and transport rate, which thereby endowing the cell with superior cycling stability with a capacity retention of 93% after 200 cycles at 1 C. Therefore, considering battery safety and performance, the GOPPH fibrous membrane could be a promising separator candidate for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Plasmon enhanced electrochemistry (PEEC), where specific electrochemical reactions are promoted due to the reduced energy barrier of the reaction processes by the light excited "hot carriers" of the plasmonic nanoparticles, has aroused tremendous interest in recent years. A deep understanding of the PEEC process becomes a key issue for facilitating PEEC catalyst design and improving PEEC performance. This concept article begins with a brief discussion of the macroscopic electrochemical method of PEEC study of the plasmonic nanoparticle ensembles. Following that, we highlight two electrochemical techniques that may possess single nanoparticle sensitivity, i. e., scanning electrochemical microscope and nano‐impact electrochemistry. The pros and cons of each technique are discussed and an outlook is given. We hope to provide the readers with the current status of PEEC to evoke reflections regarding the reaction mechanisms, performance improvement, and the utilizations to important systems. [ABSTRACT FROM AUTHOR]

Selective electrochemical production of valued chemicals is of significant importance but remains a great challenge in chemistry. Conventional approaches for enhancing reaction selectivity focus on the improvement of the catalysts themselves. In this work, we systematically studied the reaction kinetics and mass transport behavior of LaNiO3 nanocubes (LaNiO3 NCs) catalyzed hydrogen peroxide reduction reaction (HPRR) at ensemble and single nanoparticle levels using nano‐impact electrochemistry (NIE). We find that the selectivity of HPRR was altered at individual random‐walk nanoparticles as compared to their ensemble counterpart without changing the reaction kinetics, due to the significantly enhanced mass transport at single nanoparticles. This discovery offers the scope of new catalytic approaches for engineering electrochemical reactions in general. [ABSTRACT FROM AUTHOR]

Selective electrochemical production of valued chemicals is of significant importance but remains a great challenge in chemistry. Conventional approaches for enhancing reaction selectivity focus on the improvement of the catalysts themselves. In this work, we systematically studied the reaction kinetics and mass transport behavior of LaNiO3 nanocubes (LaNiO3 NCs) catalyzed hydrogen peroxide reduction reaction (HPRR) at ensemble and single nanoparticle levels using nano‐impact electrochemistry (NIE). We find that the selectivity of HPRR was altered at individual random‐walk nanoparticles as compared to their ensemble counterpart without changing the reaction kinetics, due to the significantly enhanced mass transport at single nanoparticles. This discovery offers the scope of new catalytic approaches for engineering electrochemical reactions in general. [ABSTRACT FROM AUTHOR]

Though imaging-guided multimodal therapy has been demonstrated as an effective strategy to improve cancer diagnosis and therapy, challenge remains as to simplify the sophisticated synthesis procedure for the corresponding nanoagents. Herein, an in-situ one-step reduction-encapsulated method has been reported, for the first time, to synthesize multicore-shell polydopamine-coated Ag nanoparticles (AgNPs@PDA) as a cancer theranostic agent, integrating amplified photoacoustic imaging, enhanced photothermal therapy, and photothermal promoted dual tumor microenvironment-coactivated chemodynamic therapy. The photoacoustic signal and the photothermal conversion efficiency of AgNPs@PDA nanosystem present a 6.6- and 4.2-fold enhancement compared to those of M-AgNPs-PDA (simply mixing PDA and AgNPs) derived from the increased interface heat transfer coefficient and the stronger near-infrared absorption. Importantly, AgNPs@PDA coactivated by dual tumor microenvironment (TME) enables controllable long-term release of hydroxyl radicals (·OH) and toxic Ag+, which can be further promoted by near-infrared light irradiation. Moreover, the high efficiency of AgNPs@PDA nanosystem with prominent photoacoustic imaging-guided synergistic photothermal-chemodynamic cancer treatment is also found in in vitro and in vivo studies. As a special mention, the formation mechanism of the one-step synthesized multicore-shell nanomaterials is systematically investigated. This work provides a much simplified one-step synthesis method for the construction of a versatile nanoplatform for cancer theranostics with high efficacy. [ABSTRACT FROM AUTHOR]

Alloying noble metal catalysts with early transition metals (ETMs) has shown great promise by simultaneously boosting catalytic activity and durability because of their strong electronic interactions. However, the very negative reduction potential of ETMs has posed great challenges for the synthesis of the desired alloy catalysts, not to mention the structure‐controlled synthesis. Here an autocatalytic surface reduction‐assisted strategy is reported to realize the controllable synthesis of ultrathin PtW alloy nanowires (NWs). The experimental evidence and density functional theory (DFT) calculations demonstrate that the preformed Pt NWs in the synthesis serve as the catalyst to facilitate the reduction of Wx+ species through the autocatalytic surface reduction mechanism. Using the alkaline hydrogen evolution reaction (HER) as a model reaction, the as‐synthesized PtW NWs/C catalyst shows an ultralow overpotential of 18 mV at 10 mA cm–2 and a high mass activity of 6.13 A mg–1Pt at an overpotential of 100 mV, ranking it among the most active catalysts. The dual roles of alloyed W atoms are further uncovered by theoretical simulations, involving the ensemble effect for accelerating H2O dissociation and a ligand effect for optimizing the hydrogen adsorption strength. [ABSTRACT FROM AUTHOR]

The structure–function relationship of plasmon‐enhanced electrochemistry (PEEC) is of great importance for the design of efficient PEEC catalysts, but is rarely investigated at single nanoparticle level for the lack of an efficient nanoscale methodology. Herein, we report the utilization of nanoparticle impact electrochemistry to allow single nanoparticle PEEC, where the effect of incident light on the plasmonic Ag/Au nanoparticles for accelerating cobalt metal–organic framework nanosheets (Co‐MOFNs) catalyzed hydrogen evolution reaction (HER) is systematically explored. It is found that the plasmon‐excited hot carrier injection can lower the reaction activation energy, resulting in a much promoted reaction probability and the integral charge generated from individual collisions. Besides, a plasmonic nanoparticle filtering method is established to effectively distinguish different plasmonic nanoparticles. This work provides a unique view in understanding the intrinsic physicochemical properties for PEEC at the nano‐confined domains. [ABSTRACT FROM AUTHOR]

The structure–function relationship of plasmon‐enhanced electrochemistry (PEEC) is of great importance for the design of efficient PEEC catalysts, but is rarely investigated at single nanoparticle level for the lack of an efficient nanoscale methodology. Herein, we report the utilization of nanoparticle impact electrochemistry to allow single nanoparticle PEEC, where the effect of incident light on the plasmonic Ag/Au nanoparticles for accelerating cobalt metal–organic framework nanosheets (Co‐MOFNs) catalyzed hydrogen evolution reaction (HER) is systematically explored. It is found that the plasmon‐excited hot carrier injection can lower the reaction activation energy, resulting in a much promoted reaction probability and the integral charge generated from individual collisions. Besides, a plasmonic nanoparticle filtering method is established to effectively distinguish different plasmonic nanoparticles. This work provides a unique view in understanding the intrinsic physicochemical properties for PEEC at the nano‐confined domains. [ABSTRACT FROM AUTHOR]

Dip‐pen nanolithography (DPN) is a scanning probe lithography technique that can write "inks" directly on a surface with high resolution. The "pen" was initially started from an atomic force microscopy (AFM) tip and later developed to a polydimethylsiloxane (PDMS) tip array to allow for high‐throughput nanofabrication. Over the past two decades, DPN has enabled a wide range of applications from printing arrays of small molecules to fabricating complicated hybrid structures and even integrated systems. In this review, the uses of DPN are focused upon for the synthesis of nanomaterials (NMs) divided by different postprocessing steps after the patterning. The applications of the obtained NMs are also summarized. [ABSTRACT FROM AUTHOR]

Macroscopic electrochemistry, nano-impact electrochemistry, plasmonic nanoparticles, scanning electrochemical microscope Keywords: macroscopic electrochemistry; nano-impact electrochemistry; plasmonic nanoparticles; scanning electrochemical microscope EN macroscopic electrochemistry nano-impact electrochemistry plasmonic nanoparticles scanning electrochemical microscope 1 1 1 09/27/22 20220922 NES 220922 This article overviews the progress of plasmon enhanced electrochemistry (PEEC) in terms of three types of electrochemical methods, i. e., macroscopic PEEC measurements, PEEC based on scanning electrochemical microscope, and PEEC based on nano-impact electrochemistry. [Extracted from the article]

Circulating tumor cells (CTCs) can be collected noninvasively and provide a wealth of information about tumor phenotype. For this reason, their specific and sensitive detection is of intense interest. Herein, we report a new, chip-based strategy for the automated analysis of cancer cells. The nanoparticle-based, multi-marker approach exploits the direct electrochemical oxidation of metal nanoparticles (MNPs) to report on the presence of specific surface markers. The electrochemical assay allows simultaneous detection of multiple different biomarkers on the surfaces of cancer cells, enabling discrimination between cancer cells and normal blood cells. Through multiplexing, it further enables differentiation among distinct cancer cell types. We showcase the technology by demonstrating the detection of cancer cells spiked into blood samples. [ABSTRACT FROM AUTHOR]

Circulating tumor cells (CTCs) can be collected noninvasively and provide a wealth of information about tumor phenotype. For this reason, their specific and sensitive detection is of intense interest. Herein, we report a new, chip-based strategy for the automated analysis of cancer cells. The nanoparticle-based, multi-marker approach exploits the direct electrochemical oxidation of metal nanoparticles (MNPs) to report on the presence of specific surface markers. The electrochemical assay allows simultaneous detection of multiple different biomarkers on the surfaces of cancer cells, enabling discrimination between cancer cells and normal blood cells. Through multiplexing, it further enables differentiation among distinct cancer cell types. We showcase the technology by demonstrating the detection of cancer cells spiked into blood samples. [ABSTRACT FROM AUTHOR]

A one-step electrochemical approach to the synthesis of highly dispersed Pt nanoparticles on graphene has been proposed. The resultant Pt NPs@G nanocomposite shows higher electrocatalytic activity and long-term stability towards methanol electrooxidation than the Pt NPs@Vulcan. [ABSTRACT FROM AUTHOR]

We report the size-dependent adsorption of thallium on silver nanoparticles (AgNPs) in the region of underpotential deposition; the phenomenon is observed for large nanoparticles, and bulk silver, but absent for nanoparticles below 50 nm diameter. [ABSTRACT FROM AUTHOR]