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Recently, the efficiency of p‐i‐n perovskite solar cells drastically increased, a pivotal factor being the incorporation of self‐assembled monolayers (SAMs) as a hole‐transporting layer (HTL). SAMs offer many advantages over conventional HTLs, including minimal material requirements, low cost, and facile processing. Current research is mainly focused on the development of carbazole‐derived SAMs. However, the versatility of organic chemistry allows for the design of SAMs with alternative organic cores that may possess specific benefits. In this study, three novel SAMs are incorporated in p‐i‐n perovskite solar cells, each based on an aromatic core commonly used in organic semiconductors. The novel SAMs vary in their energy level alignment with the perovskite active layer. Optimal alignment is achieved with a pyrene‐based SAM (4PAPyr), resulting in solar cells that outperform the commercially available 2PACz. Moreover, due to improved surface coverage, the use of 4PAPyr leads to a significantly higher number of working solar cell devices when compared to 2PACz, which is of particular interest with regard to upscaling. After device optimization, a power conversion efficiency of 22.2% is achieved with 4PAPyr. This research underlines the importance of diversifying SAMs to unlock further advancements in perovskite solar cell efficiency and scalability. [ABSTRACT FROM AUTHOR]

Molecular self‐assembled monolayers (SAMs), anchored on a transparent conductive oxide, serve as a class of effective hole‐selective contacts in high‐performance lab‐scale perovskite solar cells (PSCs). However, scaling these SAM‐based PSCs to large‐area modules introduces challenges, such as the de‐wetting of the perovskite ink on glass around P1 scribe zones—a part of the module design – which compromises film uniformity and reproducibility. To overcome these coverage anomalies, the study incorporates 1,3‐dimethyl‐3,4,5,6‐tetrahydro‐2(1H)‐pyrimidinone (DMPU) into the SAM solution, enhancing the interaction between the SAM and the perovskite ink and improving wettability. The approach leads to the fabrication of wide‐bandgap (1.67 eV) PSCs with power conversion efficiencies (PCEs) of up to 22.4% for small‐area devices (0.057 cm2) and 20% for perovskite mini‐modules (9.8 cm2) with high reproducibility. Additionally, the target devices demonstrate enhanced photostability, maintaining 80% of their initial PCE after 490 hours of maximum power point tracking under continuous 1‐sun illumination. This study identifies the key challenges in scaling up SAM‐based perovskite modules and presents a promising strategy for fabricating scalable SAM‐based perovskite modules. [ABSTRACT FROM AUTHOR]

The practical application of high‐energy lithium (Li) metal anodes is plagued by the severe issues of interfacial instability. The Li3N originated from the decomposition of LiNO3 is believed to endow the solid electrolyte interphase (SEI) with high stability and ionic conductivity. However, the precise control on the decomposition of LiNO3 is still challenging due to the sophisticated reaction pathways and high energy barriers. In this study, a self‐assembled monolayers (SAMs) with densely packed and long‐range ordered sulfonic acid groups on an alumina‐coated separator are designed. By providing a strong dipole moment, this SAMs efficiently facilitate the rapid and deep decomposition of LiNO3, leading to the formation of an SEI rich in Li3N nanocrystals. Notably, under the stringent conditions of 5 mA cm−2 and 5 mAh cm−2, the Li/Li symmetric cell is still able to cycle stably for 1000 h under the stable nitrided interface induced by the SAMs. Consequently, the application scenarios of SAMs technology in precisely controlling electrolyte decomposition processes are successfully expanded to stabilize the interphase of metallic Li anode with high energy‐density. [ABSTRACT FROM AUTHOR]

The practical application of high‐energy lithium (Li) metal anodes is plagued by the severe issues of interfacial instability. The Li3N originated from the decomposition of LiNO3 is believed to endow the solid electrolyte interphase (SEI) with high stability and ionic conductivity. However, the precise control on the decomposition of LiNO3 is still challenging due to the sophisticated reaction pathways and high energy barriers. In this study, a self‐assembled monolayers (SAMs) with densely packed and long‐range ordered sulfonic acid groups on an alumina‐coated separator are designed. By providing a strong dipole moment, this SAMs efficiently facilitate the rapid and deep decomposition of LiNO3, leading to the formation of an SEI rich in Li3N nanocrystals. Notably, under the stringent conditions of 5 mA cm−2 and 5 mAh cm−2, the Li/Li symmetric cell is still able to cycle stably for 1000 h under the stable nitrided interface induced by the SAMs. Consequently, the application scenarios of SAMs technology in precisely controlling electrolyte decomposition processes are successfully expanded to stabilize the interphase of metallic Li anode with high energy‐density. [ABSTRACT FROM AUTHOR]

Lately, carbazole‐based self‐assembled monolayers (SAMs) are widely employed as effective hole‐selective layers (HSLs) in inverted perovskite solar cells (PSCs). Nevertheless, these SAMs tend to aggregate in solvents due to their amphiphilic nature, hindering the formation of a monolayer on the ITO substrate and impeding effective passivation of deep defects in the perovskites. In this study, a series of new SAMs including DPA‐B‐PY, CBZ‐B‐PY, POZ‐B‐PY, POZ‐PY, POZ‐T‐PY, and POZ‐BT‐PY are synthesized, which are employed as interfacial repairers and coated atop CNph SAM to form a robust CNph SAM@pseudo‐planar monolayer as HSL in efficient inverted PSCs. The CNph SAM@pseudo‐planar monolayer strategy enables a well‐aligned interface with perovskites, synergistically promoting perovskite crystal growth, improving charge extraction/transport, and minimizing nonradiative interfacial recombination loss. As a result, the POZ‐BT‐PY‐modified PSC realizes an impressively enhanced solar efficiency of up to 24.45% together with a fill factor of 82.63%. Furthermore, a wide bandgap PSC achieving over 19% efficiency. Upon treatment with the CNph SAM@pseudo‐planar monolayer, also demonstrates a non‐fullerene organic photovoltaics (OPVs) based on the PM6:BTP‐eC9 blend, which achieves an efficiency of 17.07%. Importantly, these modified PSCs and OPVs all show remarkably improved stability under various testing conditions compared to their control counterparts. [ABSTRACT FROM AUTHOR]

Enzyme‐modified electrodes are core components of electrochemical biosensors for diagnostic and environmental analytics and have promising applications in bioelectrocatalysis. Despite huge research efforts spanning decades, design of enzyme electrodes for superior performance remains challenging. Nanoporous gold (npAu) represents advanced electrode material due to high surface‐to‐volume ratio, tunable porosity, and intrinsic redox activity, yet its coupling with enzyme catalysis is complex. Here, the study reports a flexible‐modular approach to modify npAu with functional enzymes by combined material and protein engineering and use a tailored assortment of surface and in‐solution methodologies for characterization. Self‐assembled monolayer (SAM) of mercaptoethanesulfonic acid primes the npAu surface for electrostatic adsorption of the target enzyme (flavocytochrome P450 BM3; CYT102A1) that is specially equipped with a cationic protein module for directed binding to anionic surfaces. Modulation of the SAM surface charge is achieved by electrochemistry. The electrode‐adsorbed enzyme retains well the activity (33%) and selectivity (complete) from in‐solution. Electrochemically triggered nanoscale stirring in the internal porous network of npAu‐SAM enhances speed (2.5‐fold) and yield (3.0‐fold) of the enzyme immobilization. Biocatalytic reaction is fueled from the electrode via regeneration of its reduced coenzyme (NADPH). Collectively, the study presents a modular design of npAu‐based enzyme electrode that can support flexible bioelectrochemistry applications. [ABSTRACT FROM AUTHOR]

The development and use of interface materials are essential to the continued advancement of organic solar cells (OSCs) performance. Self‐assembled monolayer (SAM) materials have drawn attention because of their simple structure and affordable price. Due to their unique properties, they may be used in inverted devices as a modification layer for modifying ZnO or as a hole transport layer (HTL) in place of typical poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) in conventional devices. In this work, zinc oxide (ZnO) is modified using five structurally similar SAM materials. This resulted in a smoother surface, a decrease in work function, a suppression of charge recombination, and an increase in device efficiency and photostability. In addition, they can introduced asfor hole extraction layer between the active layer and MoO3, enabling the use of the same material at several functional layers in the same device. Through systematic orthogonal evaluation, it is shown that some SAM/active layer/SAM combinations still offered device efficiencies comparable to ZnO/SAM, but with improved device' photostability. This study may provide recommendations for future SAM material's design and development as well as a strategy for boosting device performance by using the same material across both sides of the photoactive layer in OSCs. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of the electrochemical and anticorrosion properties of leaded α,β'-brass (CuZn39Pb3), both in its bare form and coated with an octadecanethiol self-assembled monolayer (ODT SAM). The study was conducted in a non-complexing ClO4– solution at pH3, with and without halide ions. The results demonstrate that CuZn39Pb3 exhibits good resistance to dissolution compared to lead-free diphasic brass (Cu40Zn). It is observed that the exposure time to the corrosive solution and the concentration of different halide species strongly influence the dissolution of CuZn39Pb3. The formation of ODT SAMs on CuZn39Pb3 was characterized using various techniques, and optimal conditions to obtain a compact monolayer were determined. The data show that ODT SAMs effectively suppress the selective dissolution of CuZn39Pb3 alloy. Both Tafel polarization curves and electrochemical impedance spectroscopy (EIS) results are in good agreement and demonstrate the high ability of ODT SAMs to protect the alloy against corrosion, even in the presence of halide species. Under our conditions, the ODT film primarily acts as a cathodic inhibitor and behaves as a mixed inhibitor type. Notably, F‾ ions have a minimal effect on the dezincification of the CuZn39Pb3 alloy. Inductively coupled plasma spectroscopy (ICPS) and scanning electron microscopy (SEM) results confirm the high efficiency of ODT-SAMs in preventing the corrosion of the CuZn39Pb3 alloy. This is attributed to the formation of a compact ODT layer network, which stabilizes the alloy surface and impedes the infiltration of corrosive species and water to the substrate surface. [ABSTRACT FROM AUTHOR]

The integration of self-assembled monolayers (SAM) into cobalt (Co)/porous low-dielectric-constant (low-k) dielectric interconnects is studied in terms of electrical characteristics and reliability in this work. Experimental results indicated that SAM derived from 3-aminopropyltrimethoxysilane (APTMS) improved breakdown field, time-dependent dielectric breakdown, and adhesion for Co/porous low-k integrated interconnects. However, the improvement magnitude was not large as compared to SAM in the Cu/porous low-k integration. Therefore, the integration of SAM into Co/porous low-k interconnects has a positive effect; however, in order to further promote the efficiency of SAM for Co/porous low-k interconnects, the option of precursors for the growth of SAM is required. [ABSTRACT FROM AUTHOR]

AbstractIntegration of gold nanoparticles onto electrochemical biosensor electrodes has been widely conducted to improve the performance of biosensors. Gold nanospikes (AuNS), as one of the gold nanoparticle morphologies, can be integrated into biosensors through electrodeposition and has the potential to immobilize bioreceptor on biosensors using the self-assembled monolayer (SAM) method. This paper examines the potential of AuNS-deposited Screen-Printed Carbon Electrodes (SPCEs) on immobilizing enzymes as label-based electrochemical biosensor by evaluating the optimum parameter for glucose oxidase (GOx) enzyme immobilization on the SPCE that consists of incubation time and concentration of SAM molecule—L-cysteine—and GOx enzyme, then reviews its performances. The developed biosensor exhibits excellent performance in detecting glucose (linear range of 0.2–15 mM and limit of detection (LOD) of 116 µM), with good selectivity against uric acid, urea, ascorbic acid, dopamine, and lactic acid, and superiority towards gold nanosphere modified biosensor.

Carbazole‐derived self‐assembled monolayers (SAMs) with excellent hole‐extraction and injection properties are promising hole‐transporting materials for perovskite optoelectronic devices, including perovskite solar cells (PSCs) and perovskite light‐emitting diodes (PeLEDs). The performance and thermal stability of these SAMs are heavily influenced by their chemical structure. Herein, the construction of fused carbazole‐based SAMs is proposed by expanding the π‐conjugation of the carbazole unit for application in PSCs and PeLEDs. Three proof‐of‐concept SAMs are designed and synthesized, termed XS8, XS9, and XS10, that feature highly rigid and planar fused carbazole as the donor and a conjugated alkene unit as the linker. This conjugated extension improves planarity, stability, and enhances the molecular dipole moment. Among these, XS10, with the highest degree of conjugation, demonstrated superior performance in perovskite‐based devices. The PSC device utilizing XS10 achieves a maximum power conversion efficiency (PCE) of 20.28%, surpassing the 17.19% PCE of the classic 2PACz‐based device. Similarly, the PeLED device with XS10 achieves a maximum external quantum efficiency (EQE) of 16.6%, compared to 14.5% for PEDOT‐based devices. This work provides a novel molecular design strategy for creating efficient and stable SAMs for perovskite optoelectronics and other organic electronic devices. [ABSTRACT FROM AUTHOR]

In recent years, self‐assembled monolayers (SAMs) have been proven to work efficiently as hole‐selective materials in both organic solar cells (OSCs) and perovskite solar cells. Although competitive performances are reported with these materials, a mechanistic understanding on device stability remains elusive. This study reveals that while various SAM molecules can increase the indium tin oxide (ITO) work function versus vacuum, they may not consistently result in monolayers that ensure simultaneous improvement in performance and operational stability of devices. Energetically, achieving alignment between the work function of the SAM‐modified electrode and the ionization energy (IE) of the donor is shown to be crucial for a low hole injection barrier, irrespective of the SAM's IE. Light‐induced degradation in the widely used SAM, (2‐(9H‐carbazol‐9‐yl)ethyl) phosphonic acid (2PACz), is identified through diverse aging tests and comprehensive chemical and electronic characterizations. This degradation involves SAM molecule decomposition and chemical reactions with the photoactive layer, contributing further to device degradation. Addressing these challenges, sputtered nickel oxide/SAM bilayers are proposed as hole‐selective contact with tailored interface energetics for both efficient and photostable OSCs, offering a promising alternative to commonly used hygroscopic PEDOT:PSS in OSCs. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have been proven to enhance cell characteristics by introducing passivation materials that suppress defect formation. Defect states between the electron transport layer and the absorption layer reduce electron extraction and carrier transport capabilities, leading to a significant decline in device performance and stability, as well as an increased probability of non-radiative recombination. This study proposes the use of an amino acid (L-Histidine) self-assembled monolayer material between the transport layer and the perovskite absorption layer. Surface analysis revealed that the introduction of L-Histidine improved both the uniformity and roughness of the perovskite film surface. X-ray photoelectron spectroscopic analysis showed a reduction in oxygen vacancies in the lattice and an increase in Ti4+, indicating that L-Histidine successfully passivated trap states at the perovskite and TiO2 electron transport layer interface. In terms of device performance, the introduction of L-Histidine significantly improved the fill factor (FF) because the reduction in interface defects could suppress charge accumulation and reduce device hysteresis. The FF of large-area solar modules (25 cm2) with L-Histidine increased from 55% to 73%, and the power conversion efficiency (PCE) reached 16.5%. After 500 h of aging tests, the PCE still maintained 91% of its original efficiency. This study demonstrates the significant impact of L-Histidine on transport properties and showcases its potential for application in the development of large-area perovskite module processes. [ABSTRACT FROM AUTHOR]

A highly sensitive and selective electrochemical DNA sensor based on a carboxyl functionalized graphene oxide/single-stranded DNA/6-mercapto-1-hexanol/gold electrode (COOH/ssDNA/MCH/Au) was developed for the rapid detection of Vibrio parahaemolyticus in shrimp samples. The sensor exhibited excellent selectivity, with peak current ratios of 8.3 and 4.1 for complementary to non-complementary and one-base mismatched targets, respectively. It also demonstrated a wide linear range from 10 femtomolar to 10 nM, with a low detection limit of 3 femtomolar. The reproducibility of the sensor was good, with a relative standard deviation of 4.8% for five independently fabricated electrodes. When applied to the detection of V. parahaemolyticus in spiked shrimp samples, the sensor showed high accuracy, with recovery rates ranging from 92.5 to 108.3% and relative standard deviation values below 5%. The proposed sensor outperformed most previously reported electrochemical DNA sensors for V. parahaemolyticus detection in terms of sensitivity and linear range. [ABSTRACT FROM AUTHOR]

NiOx as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency, low fabrication temperature, and superior stability. However, the mismatched energy levels and possible redox reactions at the NiOx/perovskite interface severely limit the performance of NiOx-based inverted perovskite solar cells. Herein, we introduce a p-type self-assembled monolayer between NiOx and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiOx. The self-assembled monolayer molecules all contain phosphoric acid function groups, which can be anchored onto the NiOx surface and passivate the surface defect. Moreover, the introduction of self-assembled monolayers can regulate the energy level structure of NiOx, reduce the interfacial band energy offset, and hence promote the hole transport from perovskite to NiOx layer. Consequently, the device performance is significantly enhanced in terms of both power conversion efficiency and stability. [ABSTRACT FROM AUTHOR]

Area selective deposition (ASD) is a promising IC fabrication technique to address misalignment issues arising in a top–down litho-etch patterning approach. ASD can enable resist tone inversion and bottom–up metallization, such as via prefill. It is achieved by promoting selective growth in the growth area (GA) while passivating the non-growth area (NGA). Nevertheless, preventing undesired particles and defect growth on the NGA is still a hurdle. This work shows the selectivity of Ru films by passivating the Si oxide NGA with self-assembled monolayers (SAMs) and small molecule inhibitors (SMIs). Ru films are deposited on the TiN GA using a metal-organic precursor tricarbonyl (trimethylenemethane) ruthenium (Ru TMM(CO)3) and O2 as a co-reactant by atomic layer deposition (ALD). This produces smooth Ru films (<0.1 nm RMS roughness) with a growth per cycle (GPC) of 1.6 Å/cycle. Minimizing the oxygen co-reactant dose is necessary to improve the ASD process selectivity due to the limited stability of the organic molecule and high reactivity of the ALD precursor, still allowing a Ru GPC of 0.95 Å/cycle. This work sheds light on Ru defect generation mechanisms on passivated areas from the detailed analysis of particle growth, coverage, and density as a function of ALD cycles. Finally, an optimized ASD of Ru is demonstrated on TiN/SiO2 3D patterned structures using dimethyl amino trimethyl silane (DMA-TMS) as SMI. [ABSTRACT FROM AUTHOR]

In this study, a thin poly (methyl methacrylate) coating was formed on a self-assembled monolayer formed on a gold plate after chemically binding estrone. Subsequently, the estrone molecules were hydrolyzed and extracted using a solvent to form a molecular-imprinted system. The estrone-imprinted gold plate was then used as a working electrode to measure the estrone recognition ability through electrochemical methods. The recognition ability of this working electrode was evaluated for similar compounds. The selectivity factors for the seven estrone analogs were measured, and these values ranged from 0.19 to 0.67. According to the experimental results, the estrone-imprinted system showed good differentiation of estrone from other estrone analogs. Comparing these selectivity factors with those of a previous study on a cholesterol-imprinted system, the relative molecular size difference between the target molecule and similar molecules had a significant impact on the selectivity factor. [ABSTRACT FROM AUTHOR]

Electronic immunosensors are indispensable tools for diagnostics, particularly in scenarios demanding immediate results. Conventionally, these sensors rely on the chemical immobilization of antibodies onto electrodes. However, globular proteins tend to adsorb and unfold on these surfaces. Therefore, self‐assembled monolayers (SAMs) of thiolated alkyl molecules are commonly used for indirect gold–antibody coupling. Here, a limitation associated with SAMs is revealed, wherein they curtail the longevity of protein sensors, particularly when integrated into the state‐of‐the‐art transducer of organic bioelectronics—the organic electrochemical transistor. The SpyDirect method is introduced, generating an ultrahigh‐density array of oriented nanobody receptors stably linked to the gold electrode without any SAMs. It is accomplished by directly coupling cysteine‐terminated and orientation‐optimized spyTag peptides, onto which nanobody‐spyCatcher fusion proteins are autocatalytically attached, yielding a dense and uniform biorecognition layer. The structure‐guided design optimizes the conformation and packing of flexibly tethered nanobodies. This biolayer enhances shelf‐life and reduces background noise in various complex media. SpyDirect functionalization is faster and easier than SAM‐based methods and does not necessitate organic solvents, rendering the sensors eco‐friendly, accessible, and amenable to scalability. SpyDirect represents a broadly applicable biofunctionalization method for enhancing the cost‐effectiveness, sustainability, and longevity of electronic biosensors, all without compromising sensitivity. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiOX) has a crucial role in enhancing the efficiency and stability of p‐i‐n inverted perovskite solar cells (PSCs), which hold great potential for commercialization. However, improving contact passivation between perovskites and NiOX is a challenge due to a hindered buried interface. In order to address this issue, self‐assembled monolayers (SAMs) are introduced as a buffer layer to prevent direct contact and non‐radiative recombination. While, the large dipole moment of SAMs increases the work function of NiOX, which is crucial for enhancing hole transport performance, given the low interfacial potential barrier for hole transfer. By a combination of the first‐principles calculations, drive‐level capacitance profiling, and transient absorption spectrum characterization, the understanding of the ion‐dipole interactions and interface passivation mechanism of potassium fluoride (KF) ultra‐thin buffer layer between SAMs and perovskites is provided. The efficiency of inverted PSCs as high as 23.25% is obtained, and the unencapsulated devices kept 90% of initial efficiency following 1400 h aging under nitrogen, which demonstrate remarkable long‐term stability as well. This novel strategy highlights the significance of SAMs dipole moment at the NiOX/perovskites interface and provides a new approach to address buried interfaces for high‐efficiency and long‐term stability in inverted PSCs. [ABSTRACT FROM AUTHOR]

A composite film of Ni(II) phthalocyanine bearing four benzothiazole (bs) substituents (2) and carboxylic-functionalised multi-walled carbon nanotubes (2-f-MWCNTs) was drop cast on an Au electrode and heated at 50 °C to form a new Au|2-f-MWCNTs sensor for detection of Hg(II) ions. The redox potentials of 2 were measured by cyclic voltammetry, and the processes were affirmed spectroelectrochemically. The nanocomposite of the 2-f-MWCNTs was characterised by Fourier transform Infrared and Raman spectroscopies, and Scanning electron Microscopy. Its electrocatalysis towards Hg(II) was probed by various voltammetric techniques showing higher Faradaic currents in standard redox solutions than the bare or SAMs of 2. Anodic stripping voltammgrams of Hg2+ ions at the Au|2-f-MWCNTs showed good electrocatalytic activity with a linear range spanning 14.4 μM and 1000 μM, and a precision of ± 4.2%. Electrode selectively detected Hg2+ ions in the presence of Pb2+ and Zn2+ ions, while its SWV scan for a mixture of Hg2+ and Cd2+ showed high background noise. [ABSTRACT FROM AUTHOR]

Hybrid strategies that combine conventional top-down lithography with bottom-up molecular assembly are of interest for a range of applications including nanolithography and sensors. Interest in these strategies stems from the ability to create complex architectures over large areas with molecular-scale control and precision. The molecular-ruler process typifies this approach where the sequential layer-by-layer assembly of mercaptoalkanoic acid molecules and metal ions are combined with conventional top-down lithography to create precise, registered nanogaps. However, the quality of the metal-ligated mercaptoalkanoic acid multilayer is a critical characteristic in generating reproducible and robust nanoscale structures via the molecular-ruler process. Therefore, we explore the assembly of alkanethiolate monolayers, mercaptohexadecanoic acid (MHDA) monolayers, and Cu-ligated MHDA multilayers on Au{111} substrates using atomic force microscopy and in situ dynamic spectroscopic ellipsometry. The chemical film thicknesses in situ dynamic spectroscopic ellipsometry agree with previous ex situ surface analytical methods. Moreover, in situ dynamic spectroscopic ellipsometry provides insight into the assembly process without interrupting the assembly process and potentially altering the characteristics of the resulting chemical film. By following the real-time dynamics of each deposition step, the assembly of the Cu-ligated MHDA multilayers can be optimized to minimize deposition time while having minimal impact to the quality of the chemical film. [ABSTRACT FROM AUTHOR]

Quasi‐2D (q‐2D) perovskites are extensively studied due to their hybrid properties of 3D and 2D phases and have proven to be applied to a wide range of optoelectronics. Multiple device engineering methods for perovskite photodetectors are developed. However, the treatment of self‐assembled monolayer (SAM) is rarely discussed. Herein, a series of silane‐coupling agents of (3‐chloropropyl)trichlorosilane (CPTS), phenyltrichlorosilane, and (3‐aminopropyl)triethoxysilane is adopted as SAM materials and elucidated their influence on q‐2D/3D CsPbBr3 films and their photodetector performance. The optical properties and morphology results reveal that perovskite film on CPTS‐modified surface can prolong excitons' lifetime, produce a larger grain size and better size distribution, while also present better crystallinity and united orientation. As for the fabricated photodetectors, the device on a CPTS‐modified surface has the highest photocurrent of 5.46 × 10−8 A, a responsivity of 0.16 A W−1, and an 18‐times‐higher specific detectivity than the pristine counterpart, which comes from the higher surface energy and favorable energy level alignment. The photodetector on the CPTS‐modified surface also shows better stability than that on the pristine surface. This study pioneers by using SAMs on q‐2D perovskite photodetectors and provides a facile route of device fabrication for perovskite photodetectors. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion batteries (ZIBs) are promising next‐generation energy storage devices, yet suffer from the issues of hydrogen evolution reaction (HER) and intricate side reactions on the Zn anode surface. The hydrogen (H)‐bond networks play a critical role in interfacial proton transport that may closely relate to HER but are rarely investigated. Herein, we report a self‐assembled monolayer (SAM) strategy which is constructed by anchoring ionic liquid cations on Ti3C2Tx substrate for HER‐free Zn anode. Molecule dynamics simulations reveal that the rationally designed SAM with a high coordination number of water molecules (25–27, 4–6 for Zn2+) largely reduces the interfacial densities of H2O molecules, therefore breaking the connectivity of H‐bond networks and blocking proton transport on the interface, by which the HER is suppressed. Then, a series of in situ characterizations demonstrate that negligible amounts of H2 gas are collected from the Zn@SAM‐MXene anode. Consequently, the symmetric cell enables a long‐cycling life of 3000 h at 1 mA cm−2 and 1000 h at 5 mA cm−2. More significantly, the stable Zn@SAM‐MXene films are successfully used for coin full cells showing high‐capacity retention of over 94 % after 1000 cycles and large‐area (10×5 cm2) pouch cells with desired performance. [ABSTRACT FROM AUTHOR]

The self‐assembled monolayer (SAM) is now widely applied at the hole‐selective interface of efficient inverted perovskite solar cells (PSCs). However, voids are unavoidable in SAMs due to the rough substrate and the deposition conditions, which lead to direct contact between the active layer and electrode, undermining the efficiency and stability of PSCs. Here, alkylphosphonic acids with different alkyl chain length are post‐assembled to fill the voids, thereby forming a compact po‐SAM layer. By further modifying the head group of alkylphosphonic acids, the efficiency and stability of PSCs are improved due to wetting and passivation. Finally, the po‐SAM layer formed by (2‐Bromoethyl) phosphonic acid and [4‐(3,6‐dimethyl‐9H‐carbazol‐9‐yl)butyl] phosphonic acid contributes to a champion device with the power conversion efficiency of 25.16% (certified 24.67%) and improved stability under operation or storage. This work demonstrates the advantages of po‐SAM layer in improving the performance of PSCs, offering ideas for SAM modification. [ABSTRACT FROM AUTHOR]

Perfluorododecyl iodide (I-PFC12) is of interest for area-selective deposition (ASD) applications as it exhibits intriguing properties such as ultralow surface energy, the ability to modify silicon's band gap, low surface friction, and suitability for micro-contact patterning. Traditional photolithography is struggling to reach the required critical dimensions. This study investigates the potential of using I-PFC12 as a way to produce contrast between the growth area and non-growth areas of a surface subsequent to extreme ultraviolet (EUV) exposure. Once exposed to EUV, the I-PFC12 molecule should degrade with the help of the photocatalytic substrate, allowing for the subsequent selective deposition of the hard mask. The stability of a vapor-deposited I-PFC12 self-assembled monolayer (SAM) was examined when exposed to ambient light for extended periods of time by using X-ray photoelectron spectroscopy (XPS). Two substrates, SiO2 and TiO2, are investigated to ascertain the suitability of using TiO2 as a photocatalytic active substrate. Following one month of exposure to light, the atomic concentrations showed a more substantial fluorine loss of 10.2% on the TiO2 in comparison to a 6.2% loss on the SiO2 substrate. This more pronounced defluorination seen on the TiO2 is attributed to its photocatalytic nature. Interestingly, different routes to degradation were observed for each substrate. Reference samples preserved in dark conditions with no light exposure for up to three months show little degradation on the SiO2 substrate, while no change is observed on the TiO2 substrate. The results reveal that the I-PFC12 SAM is an ideal candidate for resistless EUV lithography. [ABSTRACT FROM AUTHOR]

In this study, gold-coated quartz tuning forks (QTFs) sensing devices functionalized with self-assembled monolayers (SAM) of a lower-rim functionalized calix[4]arene methoxy ester were used for the detection of divalent Ca2+ and Pb2+ ions in aqueous solutions by utilizing adsorption behavior and the radiative effect. The gold-coated QTF functionalized calix[4]arene methoxy ester sensing device was tested by measuring the respective frequency shifts obtained using small (60 µL) samples of aqueous PbCl2 at two different concentrations (10−6 and 10−4 M). For 10−4 M solutions of PbCl2, results showed that the resonance frequency shift Δf = 317 Hz, from 32,867 Hz (fCalix) to 32,550 Hz (fCalix⊃Pb2+) due to the absorption of lead (Pb2+) ions (10-4 M) by calixl[4]arene methoxy ester receptor molecules on the QTF sensing layer from the aqueous solution to forming the ([Calix ⊃ Pb2+]) complex. The most significant frequency changes were observed at a concentration of 10−6 M CaCl2, where CaCl2 exhibited the biggest change of 356 Hz, from 32,893 Hz (fCalix) to 32,537 Hz (fCalix⊃Ca2+), compared to 317 Hz for PbCl2 (10−4 M). The limit of detection was 100 femtomolar (fM) for CaCl2 and 245 fM for PbCl2. After that, we irradiated the receptor molecules which was holding Pb2+ ions in the complex ([calix ⊃ Pb2+]) on the QTF sensing layer with a radiation dose ranging from 7.5 to 50 µGy of gamma rays from the Cesium-137 source for 30 min. Interestingly, it was observed that the resonance frequency shift (Δf = 54 Hz) back to 32,604 Hz from 32,550 Hz (f(Calix⊃Pb2+)), which strongly suggests that the Pb2+ ion removed from ([calix ⊃ Pb2+]) complex on the QTF sensing layer due to gamma radiation dose. To follow up on the radiation effect of the ([calix ⊃ Pb2+]) on the QTF sensing layer, we stopped the gamma radiation source and kept it for an additional 10 min to see if there was any resonance frequency. It was noticed that an additional resonance frequency shifted (Δf = 33 Hz) back to 32,637 Hz from 32,604 Hz after stopping the gamma radiation source for 10 min. We assume that the complex ([calix ⊃ Pb2+]) absorbs the gamma radiation and continues the removal of Pb2+ ions from the complex on the sensing layer. A similar phenomenon was also observed for the absorption of lead (Pb2+) ions (10-6 M) by calix[4]arene methoxy ester receptor molecules on the QTF sensing layer from the aqueous solution to forming the ([Calix ⊃ Pb2+]) complex. The resonance frequency shift Δf = 142 Hz, from 32,706 Hz (fCalix) to 32,564 Hz (fCalix⊃Pb2+) due to the absorption of lead (Pb2+) ions (10-6 M) by calix[4]arene methoxy ester receptor molecules on the QTF sensing layer from the aqueous solution to forming the ([Calix ⊃ Pb2+]) complex. Subsequent exposure to gamma radiation, with doses ranging from 7.5 to 50 µGy from a Cesium-137 source over 30 min, prompted a resonance frequency shift (Δf = 37 Hz) back to 32,606 Hz from 32,564 Hz (f(Calix⊃Pb2+)). This shift strongly suggests the removal of Pb2+ ions from the ([calix ⊃ Pb2+]) complex on the QTF sensing layer due to gamma radiation dose. X-ray photoelectron spectroscopy (XPS) analysis confirmed the chemical adsorption of Pb2+ ions onto the gold-coated QTFs functionalized calix[4]arene adsorbent sensing layer surface. Therefore, the technology underlying the calix[4]arene-functionalized sensing device holds promise for diverse industrial applications, supporting potential advancements in water pollution mitigation through the proposed adsorption and irradiation mechanism.

Abstract Lately, carbazole‐based self‐assembled monolayers (SAMs) are widely employed as effective hole‐selective layers (HSLs) in inverted perovskite solar cells (PSCs). Nevertheless, these SAMs tend to aggregate in solvents due to their amphiphilic nature, hindering the formation of a monolayer on the ITO substrate and impeding effective passivation of deep defects in the perovskites. In this study, a series of new SAMs including DPA‐B‐PY, CBZ‐B‐PY, POZ‐B‐PY, POZ‐PY, POZ‐T‐PY, and POZ‐BT‐PY are synthesized, which are employed as interfacial repairers and coated atop CNph SAM to form a robust CNph SAM@pseudo‐planar monolayer as HSL in efficient inverted PSCs. The CNph SAM@pseudo‐planar monolayer strategy enables a well‐aligned interface with perovskites, synergistically promoting perovskite crystal growth, improving charge extraction/transport, and minimizing nonradiative interfacial recombination loss. As a result, the POZ‐BT‐PY‐modified PSC realizes an impressively enhanced solar efficiency of up to 24.45% together with a fill factor of 82.63%. Furthermore, a wide bandgap PSC achieving over 19% efficiency. Upon treatment with the CNph SAM@pseudo‐planar monolayer, also demonstrates a non‐fullerene organic photovoltaics (OPVs) based on the PM6:BTP‐eC9 blend, which achieves an efficiency of 17.07%. Importantly, these modified PSCs and OPVs all show remarkably improved stability under various testing conditions compared to their control counterparts.

Immobilization of biomaterials is a very important task in the development of biofuel cells and biosensors. Some semiconducting metal-oxide-based supporting materials can be used in these bioelectronics-based devices. In this article, we are reviewing some functionalization methods that are applied for the immobilization of biomaterials. The most significant attention is paid to the immobilization of biomolecules on the surface of semiconducting metal oxides. The improvement of biomaterials immobilization on metal oxides and analytical performance of biosensors by coatings based on conducting polymers, self-assembled monolayers and lipid membranes is discussed. [ABSTRACT FROM AUTHOR]

Effective passivation of defects at the buried interface between the perovskite absorber and hole‐selective layer (HSL) is crucial for achieving high performance in inverted perovskite solar cells (PSCs). Additionally, the HSL needs to possess compact molecular packing and intrinsic photo‐ and thermo‐stability to ensure long‐term operation of the devices. In this study, a novel MeO‐BTBT‐based self‐assembled monolayer (SAM) is reported to serve as an efficient HSL in inverted PSCs. Compared to the well‐established carbazole‐containing SAM MeO‐2PACz, MeO‐BTBT has flat and more extended conjugation with large atomic radius of the sulfur atom. These induce stronger intermolecular interactions to enable more ordered and compact SAM to be formed on indium–tin oxide (ITO) substrates. Meanwhile, the sulfur atoms in MeO‐BTBT can coordinate with Pb2+ ions to passivate the defects at the buried interface of perovskite absorber. The derived perovskite films show both high photoluminescence (PL) quantum yield (13.2%) and a long lifetime (7.2 µs). The PSCs based on MeO‐BTBT show a PCE of 24.53% with an impressive fill factor of 85.3%. The PCEs of MeO‐BTBT‐based devices can maintain ≈95% of their initial values after being aged at 65 °C for more than 1000 h or continuous operation under 1‐sun illumination. [ABSTRACT FROM AUTHOR]

With the rapid development of emerging technologies such as artificial intelligence and high-frequency communications, advanced subnanometer chips with a high-performance computing ability have received worldwide attention. The success of subnanometer chips relies on ultrafine pitch integrated circuit (IC) manufacturing technology and "more than Moore" three-dimensional (3D) IC packaging technology. Copper (Cu) is a key conducting material used to fabricate planar and through-silicon-via Cu/SiO2/Si heterojunctions in 3D IC packaging architectures. The construction of an ultrathin diffusion barrier with a high film uniformity and adhesion strength at various Cu/SiO2/Si heterojunctions is an imperative and challenging task. In this study, we demonstrate that a molecule-based nanolayer assembled from amine-terminated silatrane is a promising diffusion barrier for blocking active atomic diffusion of Cu to Si. The breakdown temperature at which Cu silicides are formed at heterojunctions is taken as an indicator of the efficacy of the molecule-based diffusion barriers. Due to their superior structural stabilities and intermolecular networking abilities, silatranes can assemble into denser and more organized molecular nanolayers than commercially available amine-terminated silanes. Benefiting from the well-organized network structure, the silatrane-based barrier increased the breakdown temperature to 500 °C, which was greater than those seen without a barrier (400 °C) or with silane-based (450 °C) barriers. [ABSTRACT FROM AUTHOR]

Uric acid (UA) is a relevant biomarker that at abnormal levels could provide information for the timely diagnosis of chronic-degenerative diseases, such as Diabetes mellitus, cardiovascular deficiencies or gut. This work presents a simple surface functionalization of screen-printed carbon electrodes (SPCE) with cysteamine self-assembled monolayers (SAMs) assembled over electrodeposited gold nanoparticles (AuNPs). The modification allowed the immobilization of uricase enzyme, preserving its biocatalytic activity and resulting in sensitive and selective UA detection. The developed biosensor device exhibited a linear detection range from 100 μM – 1000 μM, a sensitivity of 6.622 nA/μM and a limit of detection (LOD) of 4.6 μM with selectivity to UA molecules over common interfering analytes. When evaluated in urine samples, the analytical capabilities of the PTSPCE/AuNPS/SAMs/Uox biosensor remained, achieving an average recovery rate of 126.91%. The obtained analytical parameters proved to be competitive when utilizing non-invasive fluids, suggesting the possibility of conducting detection assays with potential clinical applications using an implemented electrochemical biosensor through a simple, flexible, and reproducible methodology.

Extracellular histone proteins in the blood indicate a heightened risk of morbidity after trauma or in major illnesses such as sepsis. We present the development of an aptasensor for histone detection with an extended gate field-effect transistor (EGFET) configuration, which benefits from low power consumption, rapid response, and compatibility with miniaturized gold electrodes. Histones have a high isoelectric point and charge density, which cause them to physically adsorb to non-specific elements of the sensor that have available electrostatic charges. To combat this, the sensing surface is formed with a thiol-modified, high-affinity and histone-specific RNA aptamer sequence and by co-immobilizing with poly(ethylene glycol) methyl ether thiol (PEG) as a blocking agent. Surface plasmon resonance (SPR) is used to analyze aptamer and PEG immobilization strategies, confirm histone binding, and calculate kinetic binding constants. Through comparison of different blocking agents and time-dependent preparation, the ideal equilibrium dissociation constant (KD) is estimated to be below 200 pM, which is the upper range of extracellular histone concentrations in critically ill patients with high mortality. The EGFET sensitivity of the optimized aptasensor is 6.65 mV/decade concentration change for histone H4 with a physiologically relevant 5 pM limit of detection. Selectivity tests with 100 nM bovine serum albumin (BSA) demonstrate a signal response that is 13-fold smaller than for histones. This EGFET aptasensor platform is suitable for future point-of-care monitoring of histone levels in critically ill patients, thus permitting the early detection of increased risk and the need for more aggressive interventional measures to prevent mortality.

Abstract Electronic immunosensors are indispensable tools for diagnostics, particularly in scenarios demanding immediate results. Conventionally, these sensors rely on the chemical immobilization of antibodies onto electrodes. However, globular proteins tend to adsorb and unfold on these surfaces. Therefore, self‐assembled monolayers (SAMs) of thiolated alkyl molecules are commonly used for indirect gold–antibody coupling. Here, a limitation associated with SAMs is revealed, wherein they curtail the longevity of protein sensors, particularly when integrated into the state‐of‐the‐art transducer of organic bioelectronics—the organic electrochemical transistor. The SpyDirect method is introduced, generating an ultrahigh‐density array of oriented nanobody receptors stably linked to the gold electrode without any SAMs. It is accomplished by directly coupling cysteine‐terminated and orientation‐optimized spyTag peptides, onto which nanobody‐spyCatcher fusion proteins are autocatalytically attached, yielding a dense and uniform biorecognition layer. The structure‐guided design optimizes the conformation and packing of flexibly tethered nanobodies. This biolayer enhances shelf‐life and reduces background noise in various complex media. SpyDirect functionalization is faster and easier than SAM‐based methods and does not necessitate organic solvents, rendering the sensors eco‐friendly, accessible, and amenable to scalability. SpyDirect represents a broadly applicable biofunctionalization method for enhancing the cost‐effectiveness, sustainability, and longevity of electronic biosensors, all without compromising sensitivity.

Self-assembled monolayers (SAMs) with short organic chains terminated with specific functional groups are attractive for modifying surface properties for a variety of applications, including being a copper diffusion barrier layer on Si wafer. However, SAM formation is process-sensitive and ideal SAM is difficult to obtain, both of which need to carefully deal with before practical use. Herein we developed a system to achieve seamless electroless deposited copper (ELD Cu) film on an amino-terminated silane SAM modified Si wafer with the help of a bifunctional polyvinyl alcohol-capped Pd nanocluster (PVA-Pd) catalyst. The PVA-Pd acts as a catalyst for ELD Cu as well as a healing agent to fix defects of the amino silane SAM. The sheet resistance, cross-sectional morphology analysis and adhesion of ELD Cu on the Si wafer are extensively studied. By controlling the abundancy of PVA in PVA-Pd, the diffusion barrier property of a flawed amino-terminated silane SAM remains reliably effective even after a 500 °C rapid thermal annealing (RTA), evidencing the superior healing function of PVA. The whole thickness of the PVA-Pd/amino-terminated silane SAM before and after RTA is 〜6 nm and 〜2 nm, respectively, which is applicable for advanced microelectronic manufacturing.

This paper presents the synthesis, characterization, and electrocatalytic behavior of peripheral thiol-functionalized nickel(II) phthalocyanine (4β-NiIITTPc). The complex was synthesized and characterized using MALDI-TOF mass spectra, UV–visible, and FT-IR spectroscopies. Upon self-assembly on the Au surface from dimethylformamide solution, 4β-NiIITTPc forms via the formation of an Au-S bond. The attachment onto the Au surface was verified through Raman spectroscopy and cyclic voltammetry, with characteristic bands at 2572 and 250 cm−1 corresponding to -SH and Au-S stretching vibrations, respectively. Notably, the -SH stretching indicates that not all four -SH groups of 4β-NiIITTPc are involved in chemisorption. The resulting self-assembled film on the Au electrode exhibits well-defined oxidation peaks at +0.34 V and +0.56 V, corresponding to NiIII/NiII and NiIIPc−1/NiIIPc−2, respectively. The surface coverage was estimated from the charge associated with NiII/NiIII oxidation, yielding 1.01 × 10−10 mol cm−2. Finally, the electrocatalytic activity of the self-assembled monolayer (SAM) of 4β-NiIITTPc on Au electrodes was assessed by studying the oxidation of 3,4-dihydroxy-1-phenylalanine (L-dopa) as a probe. The SAM-modified electrode not only shifts the oxidation potential of L-dopa to a less positive potential but also enhances the oxidation current and mitigates electrode surface fouling compared to the bare Au electrode.

Prostate cancer (PCa) is the second most common cancer. In this paper, the isolation and properties of exosomes as potential novel liquid biopsy markers for early PCa liquid biopsy diagnosis are investigated using two prostate human cell lines, i.e., benign (control) cell line RWPE1 and carcinoma cell line 22Rv1. Exosomes produced by both cell lines are characterised by various methods including nanoparticle-tracking analysis, dynamic light scattering, scanning electron microscopy and atomic force microscopy. In addition, surface plasmon resonance (SPR) is used to study three different receptors on the exosomal surface (CD63, CD81 and prostate-specific membrane antigen-PMSA), implementing monoclonal antibodies and identifying the type of glycans present on the surface of exosomes using lectins (glycan-recognising proteins). Electrochemical analysis is used to understand the interfacial properties of exosomes. The results indicate that cancerous exosomes are smaller, are produced at higher concentrations, and exhibit more nega tive zeta potential than the control exosomes. The SPR experiments confirm that negatively charged α-2,3- and α-2,6-sialic acid-containing glycans are found in greater abundance on carcinoma exosomes, whereas bisecting and branched glycans are more abundant in the control exosomes. The SPR results also show that a sandwich antibody/exosomes/lectins configuration could be constructed for effective glycoprofiling of exosomes as a novel liquid biopsy marker. [ABSTRACT FROM AUTHOR]

Photodetectors are one of the most essential optoelectronics nowadays. Perovskites have emerged as one of the potential materials for photodetectors due to their high absorption efficiency over a wide range of wavelengths, high charge mobility, strong mechanical deformability, and solution processability. In this study, interfacial engineering using self‐assembled monolayers (SAMs) is explored to improve the performance of perovskite photodetectors. SAMs with different terminal groups exhibit distinct surface energy, and they all result in a reduced exciton lifetime of the perovskite due to charge transfer between polycrystalline perovskite and the SAMs. In particular, the photodetector modified with (4‐hydroxyphenyl)phosphonic acid (OH) exhibits the highest electron mobility of 0.8 cm2 V−1 s−1 under 450‐nm light illumination. In addition, it shows excellent detector performance with an ultrafast photoresponse of < 14 ms, a high photoresponsivity of 5600 AW−1, and a high specific detectivity of 5.9 × 1010 Jones at a low light intensity of 18 µW cm−2. The excellent photoresponse and device switchability are attributed to the high surface energy of OH, the resulting homogeneous perovskite film morphology, the high charge transfer efficiency, and the favorable energy level alignment. The studies provide new prospects for the development of emerging perovskite photodetectors. [ABSTRACT FROM AUTHOR]

By combining the switching ability of redox molecules with the unique fluorescence properties of quantum dots (QDs), a robust electrochemical fluorescence switch is developed here. This is realized by grafting CdSe/ZnS QDs on transparent indium tin oxide (ITO) substrates and, subsequently, modifying them with a Ferrocene (Fc) molecular monolayer. The application of oxidation/reduction voltage pulses to tune the Fc redox state leads to the tuning of the surface fluorescence output. Interestingly, the ON/OF ratio can be enhanced by reducing the distance between the redox active unit and the QD due to a more efficient electronic coupling. Remarkably, by defining a mixed‐valence state, a ternary switch has also been achieved. It is highlighted that the QD surface immobilization is key to realize this switch to avoid aggregation and fluorescence quenching in suspension. Hence, an efficient and versatile novel route to fabricate robust fluorescent redox switches is demonstrated, opening a wide avenue of possibilities to be explored in the field of sensing and information storage. [ABSTRACT FROM AUTHOR]

Organic photovoltaics (OPVs) have recently achieved efficiencies of over 19% and are well underway toward practical applications. However, issues concerning operational stability remain a major challenge ahead of OPV commercialization. Here, when replacing the conventional hole‐transporting layer PEDOT:PSS with a self‐assembled monolayer of [2‐(3,6‐dichloro‐9H‐carbazol‐9‐yl)ethyl]phosphonic acid (3,6‐Cl‐2PACz) or [2‐(4,5‐dichloro‐9H‐carbazol‐9‐yl)ethyl]phosphonic acid (4,5‐Cl‐2PACz) it is found that the T80 lifetime of PM6:BTP‐eC9‐based devices can be improved from ~100 to ~470 and over 800 h, respectively. The power conversion efficiency is also improved from 17.29% to 18.17% and 18.67%, respectively. The improved performance and prolonged photostability in 4,5‐Cl‐2PACz‐based devices stem from the stabilized vertical distribution of donor and acceptor components, reducing the energetic disorder and thus alleviating non‐radiative recombination losses. It is further found that the surface energy of 4,5‐Cl‐2PACz‐modified substrates stays constant under prolonged illumination due to the improved intrinsic photostability of 4,5‐Cl‐2PACz, supporting the robust active layer morphology. Applying 4,5‐Cl‐2PACz in a ternary device of PM6:BTP‐eC9:L8‐BO‐F delivered an efficiency of 19.05% and a T80 lifetime over 1140 h. [ABSTRACT FROM AUTHOR]

In this work, we present a multiphysics modeling approach capable of simulating electrochemical impedance spectroscopy (EIS) responses of screen-printed electrodes (SPEs) modified with self-assembled monolayers of 11-Mercaptoundecanoic acid (MUA). Commercially available gold SPEs are electrochemically characterized through experimental cyclic voltammetry and EIS measurements with 10 mM [Fe(CN)6]3−/4− redox couple in phosphate buffered saline before and after the surface immobilization of MUA at different concentrations. We design the multiphysics model through COMSOL Multiphysics® based on the 3D geometry of the devices under test. The model includes four different physics considering the metal/solution interface electrochemical phenomena, the ion and electron potentials and currents, and the measurement set-up. The model is calibrated through a set of experimental measurements, allowing the tuning of the parameters used by the model. We use the calibrated model to simulate the EIS response of MUA-modified SPEs, comparing the results with experimental data. The simulations fit the experimental curves well, following the variation of MUA concentration on the surface from 1 µM to 100 µM. The EIS parameters, retrieved through a CPE-modified Randles' circuit, confirm the consistency with the experimental data. Notably, the simulated surface coverage estimates and the variation of charge transfer resistance due to MUA-immobilization are well matched with their experimental counterparts, reporting only a 2% difference and being consistent with the experimental electrochemical behavior of the SPEs. [ABSTRACT FROM AUTHOR]

The application of self‐assembled molecules (SAM) allows inverted‐structural perovskite solar cells to accomplish high efficiencies, by virtue of their high hole conductivity and negligible parasitic absorption. However, amphiphilic SAM tend to form spherical micelles in commonly used alcoholic solvents, leading to aggregation in the resulting film. In addition, hydrophobic groups of SAM are exposed to the surroundings after being deposited on transparent substrates, responsible for the poor crystallinity of perovskite and interface quality. Therefore, it is important to study the treatment of SAM layers or SAM/perovskite interfaces for better device performance. Herein, dual regulation of SAM and perovskite is achieved via a facile posttreatment by formamidinium chloride (FACl) solution in N,N‐Dimethylformamide. First, by taking advantage of solvent rinsing, aggregations at the surface of SAM layer are alleviated. Second, FACl on the top of the SAM layer assists the crystallization of perovskite through interaction with PbI2 and reduces the defect concentration via passivating the halide vacancies at the buried interface of the device. With a more uniform SAM layer, better‐crystallized perovskite, and suppressed nonradiative recombination between them, the power conversion efficiency of the target device is improved by 20%. [ABSTRACT FROM AUTHOR]

Ultraviolet‐induced degradation has emerged as a critical stability concern impeding the widespread adoption of perovskite solar cells (PSCs), particularly in the context of phase‐unstable wide‐band gap perovskite films. This study introduces a novel approach by employing a fully aromatic carbazole‐based self‐assembled monolayer, denoted as (4‐(3,6‐dimethoxy‐9H‐carbazol‐9‐yl)phenyl)phosphonic acid (MeO‐PhPACz), as a hole‐selective layer (HSL) in inverted wide‐band gap PSCs. Incorporating a conjugated linker plays a pivotal role in promoting the formation of a dense and highly ordered HSL on substrates, facilitating subsequent perovskite interfacial interactions, and fostering the growth of uniform perovskite films. The high‐quality film could effectively suppress interfacial non‐radiative recombination, improving hole extraction/transport efficiency. Through these advancements, the optimized wide‐band gap PSCs, featuring a band gap of 1.68 eV, attain an impressive power conversion efficiency (PCE) of 21.10 %. Remarkably, MeO‐PhPACz demonstrates inherent UV resistance and heightened UV absorption capabilities, substantially improving UV resistance for the targeted PSCs. This characteristic holds significance for the feasibility of large‐scale outdoor applications. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) has garnered substantial attention due to its ability to achieve single-molecule sensitivity by utilizing metallic nanostructures to amplify the exceedingly weak Raman scattering process. However, the introduction of metal nanostructures can induce a background continuum which can reduce the ultimate sensitivity of SERS in ways that are not yet well understood. Here, we investigate the impact of laser irradiation on both Raman scattering and backgrounds from self-assembled monolayers within nanoparticle-on-mirror plasmonic nanocavities with variable geometry. We find that laser irradiation can reduce the height of the monolayer by inducing an irreversible change in molecular conformation. The resulting increased plasmon confinement in the nanocavities not only enhances the SERS signal, but also provides momentum conservation in the inelastic light scattering of electrons, contributing to the enhancement of the background continuum. The plasmon confinement can be modified by changing the size and the geometry of nanoparticles, resulting in a nanoparticle geometry-dependent background continuum in SERS. Our work provides new routes for further modifying the geometry of plasmonic nanostructures to improve SERS sensitivity. [ABSTRACT FROM AUTHOR]

The surface functionality leading to a high reversibility adsorption of melamine was determined. Four different silane coupling agents, namely, 3‐(tri‐methoxysilyl) propyl methacrylate (TMSPMA), n‐propyl tri‐methoxy‐silane (PTMS), 3‐(tri‐ethoxysilyl) propionitrile (TESPN), and tri‐methoxy‐(octadecyl) silane (OTMS) were taken for making chemical functionality methacrylate, short methyl, nitrile, and extended methyl group respectively. The adsorption behavior of melamine over the substrates with four functionalities was determined using quartz crystal microbalance (QCM). The adsorption kinetics and adsorption isotherms of the adsorption studies were analyzed. The initial adsorption rate depends on the hydrophobicity and roughness of the surfaces. However, the subsequent adsorption rate depends on the specific interaction. The data of equilibrium adsorbed mass at various equilibrium concentrations were fitted with the modified Brunauer–Emmett–Teller (BET) and Freundlich adsorption isotherms. The estimated model parameters were analyzed and compared with the reported parameters of the relevant systems. There is good agreement between our results and the reported results. In addition, very high adsorption with a very high binding constant was observed for the adsorption of melamine OTMS surface. On the other hand, high adsorption with an intermediate layer binding constant for the adsorption of melamine on the methacrylate surface was observed. Based on this, we propose using acrylate chemical functionality to develop molecularly imprinted polymer‐based melamine sensors. [ABSTRACT FROM AUTHOR]

Many charged organic molecules behave as persistent and hazardous pollutants with harmful effects on human health and ecosystems. They are widely distributed related to their charged molecular structure that provides water solubility. In order to track the fate and behavior of such pollutants, charged dyes with specific absorption in the visible spectra serve as convenient model compounds. We provide a platform of smart adsorbers that efficiently remediate positively and negatively charged dyes (crystal violet and Amaranth) from water. Metal oxide nanoparticles serve as a core with an intrinsically large surface area. The surface potential was tuned towards positive or negative by decorating the cores with self‐assembled monolayers of dedicated long‐chained phosphonic acid derivatives. Selective remediation of the dyes was obtained with corresponding oppositely charged core‐shell nanoparticles. Mixed dye solution can be cleaned by a cascade approach or by applying both particle systems simultaneously. The removal efficiency was determined as a function of particle concentration via UV‐spectroscopy. The results of remediation experiments at different pH values and using superparamagnetic iron oxide nanoparticle cores lead to a simple process with recycling capability. [ABSTRACT FROM AUTHOR]

Hybrid lipid bilayers (HLBs) are rugged biomimetic cell membrane interfaces that can form on inorganic surfaces and be designed to contain biologically important components like cholesterol. In general, HLBs are formed by depositing phospholipids on top of a hydrophobic self-assembled monolayer (SAM) composed of one-tail amphiphiles, while recent findings have shown that two-tail amphiphiles such as inverse phosphocholine (CP) lipids can have advantageous properties to promote zwitterionic HLB formation. Herein, we explored the feasibility of fabricating cholesterol-enriched HLBs on CP SAM-functionalized TiO2 surfaces with the solvent exchange and vesicle fusion methods. All stages of the HLB fabrication process were tracked by quartz crystal microbalance-dissipation (QCM-D) measurements and revealed important differences in fabrication outcome depending on the chosen method. With the solvent exchange method, it was possible to fabricate HLBs with well-controlled cholesterol fractions up to ~65 mol% in the upper leaflet as confirmed by a methyl-β-cyclodextrin (MβCD) extraction assay. In marked contrast, the vesicle fusion method was only effective at forming HLBs from precursor vesicles containing up to ~35 mol% cholesterol, but this performance was still superior to past results on hydrophilic SiO2. We discuss the contributing factors to the different efficiencies of the two methods as well as the general utility of two-tail CP SAMs as favorable interfaces to incorporate cholesterol into HLBs. Accordingly, our findings support that the solvent exchange method is a versatile tool to fabricate cholesterol-enriched HLBs on CP SAM-functionalized TiO2 surfaces. [ABSTRACT FROM AUTHOR]

Fluorescence probe technology holds great promise in the application of trace explosive detection due to its high sensitivity, fast response speed, good selectivity, and low cost. In this work, a designed approach has been employed to prepare the TPE-PA-8 molecule, utilizing the classic aggregation-induced emission (AIE) property of 1,1,2,2-tetraphenylethene (TPE), for the development of self-assembled monolayers (SAMs) targeting the detection of trace nitroaromatic compound (NAC) explosives. The phosphoric acid acts as an anchoring unit, connecting to TPE through an alkyl chain of eight molecules, which has been found to play a crucial role in promoting the aggregation of TPE luminogens, leading to the enhanced light-emission property and sensing performance of SAMs. The SAMs assembled on Al2O3-deposited fiber film exhibit remarkable detection performances, with detection limits of 0.68 ppm, 1.68 ppm, and 2.5 ppm for trinitrotoluene, dinitrotoluene, and nitrobenzene, respectively. This work provides a candidate for the design and fabrication of flexible sensors possessing the high-performance and user-friendly detection of trace NACs. [ABSTRACT FROM AUTHOR]