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Flexible graphene‐based paper electrodes (FGPEs) are a new class of study and the research on this electrode material has been carried out for approximately ten years. FGPEs have many advantages compared to classical solid electrodes such as being flexible, foldable, adaptable to flexible electronics, being cut, easily shaped, and effective and adjustable modification. In this work, the applicability of FGPEs modified with polyindole (PIN) thin films and zinc oxide nanoparticles (ZnO‐NPs) to energy‐storage systems as a supercapattery design is presented, and especially the limitations of ZnO‐NPs for energy‐storage applications are revealed to inform researchers working for a similar purpose. Capacitance calculations have been performed using both cyclic voltammetry (CV) and galvanostatic charge‐discharge (GCD) experiments. It was observed that the rGO/PIN paper demonstrated almost 30 times more energy‐storage capacity than that of the rGO/PIN/ZnO paper due to the electrochemical instability of ZnO‐NPs on the flexible electrode platform at the applied potential region in 1.0 M HClO4 solution. The rGO/PIN paper with a highly flexible property exhibited an energy density of 74.5 W h cm−2 and a power density of 2258 W cm−2 at a current density of 2.2 mA cm−2, revealing hopeful results for future modular and flexible approaches. [ABSTRACT FROM AUTHOR]

Food is necessary for survival, and contamination can shorten humans' lives on Earth in all dimensions. Real‐time screening of food pollutants, such as toxins, infectious agents, and chemical contaminants, is in high demand today. Thus, a cost‐effective and ecologically benign technology must be developed to detect food contamination in a rapid fashion. Nanoparticle (NP)‐based paper sensors are one of the most important alternatives to traditional methods because these are simple, inexpensive, highly selective, and sensitive tools. This article provides an overview of NP‐based paper sensor techniques for detecting toxic food contaminants. [ABSTRACT FROM AUTHOR]

TiO2 nanoparticles can improve the electrical performance of oil paper insulation. In this study, 10 nm TiO2 nanoparticles were prepared and dispersed into transformer oil, and then immerse pressboards in it to obtain nanofluid impregnated pressboards (NP). Its thermal aging was accelerated together with the reference sample at 130°C for 36 days. Analyzing the acid value in the oil, polymerization degree, surface topography, AC breakdown strength, surface flashover characteristics and surface potential decay characteristics. It was observed that TiO2 nanoparticles can reduce the acid value and improve AC breakdown strength of oil. However, the degree of polymerization and surface appearance of NP and oil impregnated pressboards (OP) during thermal aging did not differ significantly. During the aging process, the energy level of pressboard surface traps shifted first towards the shallow and then gradually towards the deep. During all the aging stages, the surface flashover voltage of NP was always higher or close to that of OP. The mechanism of TiO2 nanoparticles improving the breakdown and surface flashover characteristics of oil–paper insulation during thermal aging is discussed from the perspective of water molecules and aging by‐products adsorption and introduction of shallow traps by nanoparticles. [ABSTRACT FROM AUTHOR]

The present study reports the fabrication of reduced graphene oxide (rGO)/gold nanoparticles (AuNP) nanocomposites modified cellulose fiber paper‐based electrochemical biosensor for procalcitonin (PCT) biomarker detection. PCT is a biomarker specific for bacterial infection (BI) detection and has gained much attention as a potential solution to the problems associated with determining appropriate antibiotic use. In sepsis and other severe infections, serum PCT levels increase to values above 100 ng mL−1 in response to pro‐inflammatory stimulation. The structural and morphological characterization of the rGO‐AuNP composite are investigated using UV‐Vis spectroscopy, FTIR spectroscopy, X‐ray diffraction, and scanning electron microscopy. Monoclonal antibodies specific to PCT were covalently immobilized onto the rGO‐AuNP nanocomposite modified paper to fabricate an electrochemical biosensor. The fabricated biosensor exhibits linearity in the PCT concentration range 10 −15×103 pg mL−1, with a low detection limit 10 pg mL−1. Furthermore, the proposed biosensor also exhibited good selectivity and could detect PCT biomarkers even in the presence of other interfering electroactive species such as glucose, oxalic acid, and urea. The proposed CF‐based biosensor has been proven as an accelerated simple point‐of‐care (POC) exploratory approach for early PCT diagnosis in inadequate areas with limited production facilities, computational techniques, and highly skilled experts. [ABSTRACT FROM AUTHOR]

Herein, we prepared a bisuppport‐based bimetallic nanoparticle composite AuFe/ZIF‐8‐graphene. It exhibited high peroxidase activity compared to those hybrids without graphene support, which demonstrated the regulatory effect of graphene on the catalytic activity. SEM, TEM, EDX, XRD, FT‐IR and XPS characterization showed that Au and Fe3O4 NPs were successfully immobilized on ZIF‐8‐rGO carriers. Kinetic analysis confirmed that the fabricated composites showed better Km and Vmax for H2O2 than HRP and some other reported peroxidase mimics. Under the optimal conditions, a sensing assay for H2O2 determination was constructed with a linear detection range of 0.01–2.5 mM and a detection limit of 0.63 μM. On this basis, a colorimetric test paper with its standard card was prepared for rapid visualization detection. It realized H2O2 detection in the range of 0.01‐500 mM and was further successfully applicated in the semi‐quantitative detection of H2O2 in actual spiked water samples. This achievement was expected to encourage the development of rapid visual detection for other pollutants in environmental and medical field. [ABSTRACT FROM AUTHOR]

The discovery and characterization of nanoparticles represent a multidisciplinary issue. Their properties and applications within many fields depend on their size, shape, aspect ratio, and so on. No single methodology can currently analyze all characteristics and reveal their influence on the specific performance. Here, antibacterial and mechanical properties are investigated of three different ZnO nanoparticles (cubes, rods, and pellets) incorporated in the cellulose matrix in order to examine the correlation between the physical and chemical characteristics and antibacterial/mechanical activities. Therefore, various particles of ZnO with different sizes, shapes, and aspect ratios are synthesized via simple precipitation method in an aqueous solution and evaluated as an antimicrobial agent against Gram‐positive and Gram‐negative model bacteria alongside the commercial ZnO powder. The bactericidal activity is evaluated as prepared cellulose/ZnO nanocomposites in the form of paper sheets. Additionally, the tests of mechanical properties of the fabricated paper sheets are carried out according to ISO 5270 standard. Microscopic and spectroscopic methods are utilized to investigate the psychic‐chemical properties of the products. This study highlights that there is a strong impact of the shape, size, and aspect ratio of ZnO particles on the antibacterial efficacy and mechanical response of the fabricated cellulose‐based paper. [ABSTRACT FROM AUTHOR]

The flexible electrodes are the crucial components for fabricating wearable supercapacitors. In this study, we present a quick and convenient method to prepare graphene paper (GP) as a flexible current collector on a large scale by an easy one‐step method. The composite electrode integrated with GP and MnO2 as a flexible supercapacitor was obtained by an electrochemical deposition method without using binder or conductive agent. The substrate (GP) of electrode not only provides mechanical strength, but also contributes energy storage capacity. The MnO2 nanoparticles deposited on the surface of GP further improved the electrochemical performance of composite. The neat GP can give a specific capacitance of 184 F/g at a current density of 1 A/g. At a current density of 1 A/g, the specific capacitance of the GP/MnO2 composite with a deposition time of 30 s is as high as 410 F/g. The method presented here shows great potential for the development of flexible electrode materials in practical energy storage devices. [ABSTRACT FROM AUTHOR]

The appearance or printing quality of paper surfaces is mostly characterized by their glossiness, measured with a glossmeter as specular reflectance. The gloss properties of a base paper substrate can be improved after application of a poly(styrene-co-maleimide) nanoparticle coating under pure conditions or in the presence of different vegetable oils. The specular gloss properties of 11 different nanoparticle paper coatings have been determined under 75° and 85° incident light angles, with good relation between values along parallel (machine) and perpendicular (transverse) direction. The gloss properties for the different coatings have been further related to the surface topography. Therefore, the statistical and spatial surface roughness parameters have been studied in detail at two length scales including non-contact profilometry (1 × 1 mm2) and atomic force microscopy (2 × 2 μm2). Based on values of the Rayleigh parameter for non-contact profilometry, the surfaces can be considered as optically rough. The gloss values cannot be directly related to statistical surface roughness parameters. Otherwise, an experimental power-law model for gloss has been proposed as a function of (β/Sq) with correlation length β and root-mean-square roughness Sq. A best-fit model illustrates that gloss properties of various nanoparticle paper coatings mainly relate to the spatial surface roughness parameters determined from non-contact profilometry. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 596-610, 2016 [ABSTRACT FROM AUTHOR]

A versatile method for the preparation of efficient and reusable nanocatalysts involving the painting of a commercial filter paper with a Pd@CNT (CNT=carbon nanotubes) ink was herein explored. The resulting paper-based material provided excellent results in the semihydrogenation of alkynes and alkynols and could be recycled at least five times without loss of activity or selectivity. [ABSTRACT FROM AUTHOR]

Paper based microfluidic devices have emerged as a simple and low cost platform for efficient clinical diagnostics. An effort has been made in the present work to develop a microfluidic cholesterol biosensor using paper based platform. Microfluidic channels have been fabricated by patterning filter paper (Whatman 1) using photolithography. SU 8 photoresist formed a hydrophobic barrier on the paper with microchannels of dimensions 1000 μm(w)×100 μm(t). A three electrode system was fabricated by simple mask printing of graphite as the working, as well as the counter electrodes, and silver as the reference electrode. The working electrode was modified using nickel oxide nanoparticles prepared using co-precipitation method. Cholesterol oxidase enzyme is spotted on the test zone and chronoamperometric measurements are taken for different concentrations of cholesterol in the range of 0.12-10.23 mM, giving a quick and sensitive detection with a sensitivity of 24 µA mM−1 cm−2. [ABSTRACT FROM AUTHOR]

Cellulose‐based artefacts are highly prone to degradation, especially in the presence of acidic compounds, which trigger the depolymerization of cellulose chains and lead to a loss in the original mechanical resistance of the material. Calcium hydroxide nanoparticles dispersed in organic solvent have been recently proposed for the deacidification of cellulose‐based artworks. In this work, changes induced on paper by a deacidification treatment, following an acidification bath, were studied by nuclear magnetic resonance (NMR) relaxometry and by the so‐called NMR diffraction of water trapped in the cellulose network. The deacidification treatment modifies intrachain and interchain bonds in hydrolyzed and degraded cellulose, leading to a buffered cellulose network configuration, which is similar to that characterizing the untreated reference sample in terms of relaxation parameters. Overall, calcium hydroxide nanoparticles are demonstrated effective in hindering the degradation of cellulose induced by acids and ageing in strong environmental conditions, even from the standpoint of cellulose network arrangement. It is worth noting, too, that the unilateral NMR device used for the relaxation measurements may represent a powerful tool for the preservation of cellulose‐based artworks because it allows for the monitoring of the conservation status of cellulose in a completely non‐invasive manner. [ABSTRACT FROM AUTHOR]

Nile red has been an alternative reagent for detecting latent fingerprints on wetted substrates. However, the presence of methanol in nile red solution could make injury to handlers and destroy the traces on surfaces, such as texts on thermal papers. A novel small particle reagent formulation constituting of mesoporous silica nanoparticles (MSNs) based on nile red was prepared to overcome the problem. Compared with the conventional reagents Oil Red O or nile red solution, the nile red‐loaded MSNs are highly selective to lipid residues of fingerprints and showed a greater ability to develop clear, sharp, and detailed fingerprints on thermal papers after these were immersed in water. In addition, it can retain texts on the thermal papers well and use only water as a solvent. These suggested that nile red‐loaded MSNs are a safe, efficient, and convenient method to develop latent fingerprints on wide range of substrates of forensic importance. [ABSTRACT FROM AUTHOR]

The commercial demand for carbon nanoparticles and graphene nanoflakes are high due to their diverse usage over the past few years. However, large scale production processes are quite laborious and time consuming relying mainly on high energy and inert atmospheric condition. Herein, the abrasion technique has been utilized to exfoliate carbon nanoparticles and graphene nanoflakes from willow charcoal stick and graphite rod, respectively. The role of sandpaper in polishing is quite immense for the isolation of nanocarbons from willow charcoal and graphite. Transmission electron microscope (TEM) confirmed the formation of carbon nanoparticles whereas, high resolution transmission electron microscope (HRTEM) and atomic force microscope (AFM) topography revealed the formation of few layers of graphene nanoflakes. This entire green process was economically viable for scalable preparation of nanocarbons at room temperature and completely independent of inert conditions, usage of solvents, chemicals and the problem of by‐product formation.)) [ABSTRACT FROM AUTHOR]

The present work reports on the handwriting of electronic circuits on paper based on the deposition of an inorganic oxide semiconductor, exploiting the pen‐on‐paper (PoP) approach. The method relies on the use of a parallel metal plate pen, well known from calligraphy applications, which permits controlled deposition of a continuous zinc oxide (ZnO) dual‐phase layer on conventional printing paper. The hand‐drawn ZnO film exhibits a continuous and uniform surface with a thickness of roughly 1.5 µm, allowing the application as active layer for UV sensors and field effect transistors on paper. Photocurrent generated from the UV radiation reaches values up to 3.4 mA cm−2 with switching times on the order of few seconds. The final written paper transistors, where paper plays simultaneously the role of substrate and dielectric, reaches On/Off current ratios (IOn/IOff) of about two orders of magnitude and field effect mobility close to 5 × 10−3 cm2 V−1 s−1. As a final proof‐of‐concept a common source amplifier showing clear inverting characteristics is fabricated using a PoP written driving ZnO‐based transistor and a pencil‐drawn track as the load resistance. [ABSTRACT FROM AUTHOR]

Abstract: A potentially universal approach is presented for enzyme attachment to cellulose that significantly enhances enzyme stability while retaining high activity, and involves no chemical functionalization of cellulose. Bovine serum albumin (BSA) was interlocked in cellulose to form a protein‐friendly surface (named BSA‐Paper), while also providing COOH and NH2 groups for subsequent attachment of enzymes. The desired enzyme is then mixed with additional BSA and interlocked on BSA‐Paper. The second BSA layer dilutes and crosslinks the enzyme for improved stability. Laccase was tested as a model enzyme for interlocking on BSA‐Paper, and was found to retain over 100 % activity and was 240 times more stable at 25 °C (half life=180 d) than laccase. This new approach was also tested with a few other enzymes with encouraging results, thus providing a potentially universal method for stabilization of enzymes on cellulose with retention of high activities. [ABSTRACT FROM AUTHOR]

Iron hydroxide (Fe(OH)3) nanoparticles have garnered considerable attention for their effectiveness in water treatment. This paper reviews recent studies on the photocatalytic degradation of phenol using Fe(OH)3, detailing the synthesis procedure, photocatalytic reaction conditions under UV‐C and catalyst amount optimization. Iron hydroxide was synthesized using a facile precipitation method, and the produced catalyst was thoroughly characterized using XRD, FTIR, UV‐DRS, DTA/TGA and SEM. Characterization results indicated that the catalyst exhibited very low crystallinity, a 1.84 eV band gap, and very small particle sizes. The study investigated the degradation performance of phenol for different amounts of iron hydroxide, ranging from 0.1 g to 1 g, and determined the optimum catalyst amount to be 0.7 g. The catalyst demonstrated a degradation efficiency for phenol exceeding 90 % at the end of a 180 minute photocatalytic reaction. The paper offers a comprehensive analysis of Fe(OH)3 as a photocatalyst for phenol degradation, highlighting its potential for future applications in water treatment. [ABSTRACT FROM AUTHOR]

Abstract: A novel ultra‐low‐cost biochemical analysis platform to quantify protein dissociation binding constants and kinetics using paper microfluidics is reported. This approach marries video imaging with one of humankind's oldest materials: paper, requiring no large, expensive laboratory equipment, complex microfluidics or external power. Temporal measurements of nanoparticle–antibody conjugates binding on paper is found to follow the Langmuir Adsorption Model. This is exploited to measure a series of antibody–antigen dissociation constants on paper, showing excellent agreement with a gold‐standard benchtop interferometer. The concept is demonstrated with a camera and low‐end smartphone, 500‐fold cheaper than the reference method, and can be multiplexed to measure ten reactions in parallel. These findings will help to widen access to quantitative analytical biochemistry, for diverse applications spanning disease diagnostics, drug discovery, and environmental analysis in resource‐limited settings. [ABSTRACT FROM AUTHOR]

A foldable array of patterned graphene/ZnO nanoparticle UV sensor and asymmetric micro-supercapacitors (AMSCs) integrated on a paper substrate with patterned liquid metal interconnections is reported. The resistor type UV sensor based on graphene/ZnO nanoparticles is patterned to be driven by the stored energy of the integrated AMSCs. The AMSC consists of MnO2 nanoball deposited multiwalled carbon nanotubes (MWNTs) and V2O5 wrapped MWNTs as positive and negative electrodes, respectively. As an electrolyte, propylene carbonate-poly(methyl methacrylate)-LiClO4, an organic solvent-based gel, is used. The UV sensor and AMSCs can be easily integrated on a liquid metal, Galinstan, patterned, waterproof mineral paper and show a mechanically stable UV sensing, regardless of repetitive folding cycles. This work demonstrates a novel foldable nanomaterial based sensor system driven by integrated energy storage devices, applicable to future wearable and portable electronics. [ABSTRACT FROM AUTHOR]

A highly flexible and free-standing paper with high antibacterial activity made from silver nanoparticle (AgNP)-decorated ultralong hydroxyapatite nanowires (HAPNWs) is reported. The HAPNWs@AgNPs nanocomposites were obtained from a facile one-step solvothermal process and utilized for the construction of highly flexible and free-standing inorganic paper through a simple vacuum-filtration procedure. The structure and properties of the HAPNWs@AgNPs paper were characterized in detail. Scanning electron microscope (SEM) and transmission electron microscope (TEM) micrographs show that AgNPs are highly dispersed and stabilized in the nanocomposite and exhibit a narrow particle size distribution. The effects of the concentration of silver nitrate, solvothermal temperature and time on the product were systematically investigated. This method is simple, convenient and reproducible. The as-prepared HAPNWs@AgNPs paper shows long-time sustained silver-ion release, high antibacterial activity against both Gram-negative and Gram-positive bacteria, and good biocompatibility. Overall, this work provides a novel pathway for the preparation of a new type of highly flexible, free-standing and antibacterial inorganic paper made from silver nanoparticle-decorated hydroxyapatite nanowires for various applications, as a promising functional biomaterial. [ABSTRACT FROM AUTHOR]

This paper demonstrates, for the first time, the use of paper-based electrochemical devices coupled to external solid working electrodes. The paper-based electrochemical cells were fabricated using inexpensive and largely available office paper, according to a simple protocol that consists on the creation of hydrophobic barriers using paraffinized paper and preheated metal stamp. The counter and reference electrodes were integrated to the paper platform through the deposition of carbon and silver inks, respectively. The electrochemical paper analytical device (ePAD) was coupled to external glassy carbon rod electrode modified with reduced graphene oxide doped with Cu nanoparticles through meniscus configuration. The analytical usefulness of this electrochemical approach was demonstrated through the simultaneous determination of paracetamol and caffeine in biological samples. The analytes were successfully quantified in real urine samples and limits of detection of 24.6 nM (paracetamol) and 36.1 nM (caffeine) were obtained. The paper platform showed good stability (RSD of 1.07 % for the peak currents and 1.43 % for the peak potentials) and satisfactory performance. The use of solid electrodes coupled to paper electrochemical devices, firstly demonstrated here, opens new possibilities for the utilization of ePADs in electrochemistry and electroanalytical chemistry and offers advantages such as the extremely reduced consumption of reagents and the minimal generation of wastes. [ABSTRACT FROM AUTHOR]

Abstract: A wide band flexible substrate based metamaterial is presented. The metamaterial is fabricated on photo paper using conductive nanoparticle ink targeting flexibility applications. The metamaterial structure shows a wide double negative region of 1.848 GHz (8.298–10.146 GHz). The transmission coefficient of the proposed metamaterial has been measured and verified with simulated one. The perceptible novelties of the proposed work are its simplicity, cost effectiveness, and flexibility with covering wide X‐band microwave spectra. [ABSTRACT FROM AUTHOR]

A single-step laser scribing process is used to pattern nanostructured electrodes on paper-based devices. The facile and low-cost technique eliminates the need for chemical reagents or controlled conditions. This process involves the use of a CO2 laser to pyrolyze the surface of the paperboard, producing a conductive porous non-graphitizing carbon material composed of graphene sheets and composites with aluminosilicate nanoparticles. The new electrode material was extensively characterized, and it exhibits high conductivity and an enhanced active/geometric area ratio; it is thus well-suited for electrochemical purposes. As a proof-of-concept, the devices were successfully employed for different analytical applications in the clinical, pharmaceutical, food, and forensic fields. The scalable and green fabrication method associated with the features of the new material is highly promising for the development of portable electrochemical devices. [ABSTRACT FROM AUTHOR]

A simple and efficient pen-on-paper approach is designed to prepare hydrophilic surface enhanced Raman scattering (SERS)-active lines by directly writing on a piece of hydrophobic poly (L-lactic acid) nanofibrous paper using a pen filled with plasmonic nanoparticle ink. The pen-on-paper-line SERS substrate exhibits hydrophobic-hydrophilic focusing effects together with negligible background interference, high sensitivity, good reproducibility, and long-term stability. Furthermore, just by drawing three different plasmonic nanoparticles, the SERS activity is optimized for different molecules. Considering the complex factors involved in SERS effects of real analytes, our results provide an efficient strategy to produce optimized SERS substrates with multiple plasmonic nanoparticles. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Manganese dioxides (MnO2) are considered one of the most attractive materials as an oxygen evolution reaction (OER) electrode due to its low cost, natural abundance, easy synthesis, and environmental friendliness. Here, metal-ion (Fe, V, Co, and Ni)-doped MnO2 ultrathin nanosheets electrodeposited on carbon fiber paper (CFP) are fabricated using a facile anodic co-electrodeposition method. A high density of nanoclusters is observed on the surface of the carbon fibers consisting of doped MnO2 ultrathin nanosheets with an approximate thickness of 5 nm. It is confirmed that the metal ions (Fe, V, Co, and Ni) are doped into MnO2, improving the conductivity of MnO2. The doped MnO2 ultrathin nanosheet/CFP and the IrO2/CFP composite electrodes for OER achieve a low overpotential of 390 and 245 mV to reach 10 mA cm−2 in 1 m KOH, respectively. The potential of the doped composite electrode for long-term OER at a constant current density of 20 mA cm−2 is much lower than that of the pure MnO2 composite electrode. [ABSTRACT FROM AUTHOR]

A single-step laser scribing process is used to pattern nanostructured electrodes on paper-based devices. The facile and low-cost technique eliminates the need for chemical reagents or controlled conditions. This process involves the use of a CO2 laser to pyrolyze the surface of the paperboard, producing a conductive porous non-graphitizing carbon material composed of graphene sheets and composites with aluminosilicate nanoparticles. The new electrode material was extensively characterized, and it exhibits high conductivity and an enhanced active/geometric area ratio; it is thus well-suited for electrochemical purposes. As a proof-of-concept, the devices were successfully employed for different analytical applications in the clinical, pharmaceutical, food, and forensic fields. The scalable and green fabrication method associated with the features of the new material is highly promising for the development of portable electrochemical devices. [ABSTRACT FROM AUTHOR]

Nanocrystalline mullite has been synthesized by sintering of absorbed monophasic aluminosilicate precursors into cotton wool and filter paper cellulosic structures. Effects of molybdenum and tungsten doping on template mediated mullite at 1200°C and 1400°C have been investigated using differential thermal analysis ( DTA), X-ray diffraction analysis ( XRD), Fourier transform infrared spectroscopy ( FTIR) and field emission scanning electron micrographs ( FESEM). Microstructures of the sintered samples revealed successful replication of cellulosic structure with the formation of dense mullite phases having grain diameter in the range of 50-80 nm. Strong photoluminescence emissions in the UV and visible regions result from the oxygen vacancies and Al-O bonds present in mullite structures. [ABSTRACT FROM AUTHOR]

The modern and rapidly developing paper and board industry requires more efficient agents for the surface of paper in order to improve the mechanical properties. The starch coating used for the reinforcement of schrenz (110 g/m2) contained ultrasonicated nanoparticles of the mineral sepiolite. The viscosity of starch dispersions modified with different concentration of sepiolite was followed at the temperature of the coating on schrenz. The values of the breaking length, bursting strength and CMT-strength of the paper reinforced with modified starch were increased by up to 20%. The viscoelastic properties as storage modulus were increased, too. Scanning electron microscopy of the samples showed deagglomeration and homogeneity of the sepiolite nanoparticles. [ABSTRACT FROM AUTHOR]

We have developed nanoparticle-embedded paper-spray mass spectrometry for studying three types of heterogeneously catalyzed reactions: 1) Palladium-nanoparticle-catalyzed Suzuki cross-coupling reactions, 2) palladium- or silver-nanoparticle-catalyzed 4-nitrophenol reduction, and 3) gold-nanoparticle-catalyzed glucose oxidation. These reactions were almost instantaneous on the nanocatalyst-embedded paper, which subsequently transferred the transient intermediates and products to a mass spectrometer for their detection. This in situ method of capturing transient intermediates and products from heterogeneous catalysis is highly promising for investigating the mechanism of catalysis and rapidly screening catalytic activity under ambient conditions. [ABSTRACT FROM AUTHOR]

Covid‐19 has given us a new way to look at our globe with regards to minimise air and noise pollution and thereby upgrading global environmental conditions. This positive pandemic outcome indicates that green energy is the future of energy, and one new origin of green energy is lithium‐ion batteries (LIBs). Electric vehicles are constructed with LIBs, but they have a number of disadvantages, including poor thermal performance, thermal runaway, fire dangers and a higher discharge rate in low‐ and high‐temperature conditions. The underlying fault of LIBs is their temperature reactivity. Extreme temperatures and challenging working circumstances can cause lithium‐ion cells to malfunction and cause the battery pack (BP) to overheat. For optimal performance in vehicles and long‐term LIB durability, LIBs must be thermally managed within their operating temperature span. This paper presents an overview of several cooling strategies used to maintain the internal BP temperature. This paper discusses cooling techniques using air, liquid and phase change material (PCM), heat pipe. Additionally, various BP configurations and heat generation techniques are explored. This research also discusses the usage of nanomaterials to address the BP's heat‐related problems. This study emphasises the use of nanomaterial to boost the heat conductivity of coolant in order to raise the batteries temperature into their ideal working range (PCM as well as liquid cooling). This article also provides some of the research gaps that have been found and the crucial areas on which attention should be directed in order to build the best lithium‐ion battery thermal management system technology. [ABSTRACT FROM AUTHOR]

The current paper has the objective of exploring the thermophysical properties (TPPs) of single walled carbon nanotube (SWCNT) nanofluids (NFs) for heat transfer applications. The effect of dispersing the nanotubes in conventional heat transfer fluids (HTFs) has been investigated. Carbon nanotubes (CNTs) have exceptionally high thermal conductivities. Using the effective medium theory, density, specific heat, thermal conductivity, and viscosity has been evaluated as functions of volume fractions. The base fluids considered in this work are water, ethylene glycol, engine oil, and kerosene oil as these are the commonly used HTFs for industrial applications. Theoretical predictions from this study show an increase in density, thermal conductivity, and viscosity with volume fraction while there is a decrease in specific heat with volume fraction. The effect of the aspect ratio (AR) of CNTs on the thermal conductivity of NF is also investigated. For low volume fractions of SWCNT, the thermal conductivity has been found to increase with AR. Further, this study has been extended for a real‐world application of heat transfer using SWCNT. In this paper, a numerical investigation of heat transfer in a square enclosure with differentially heated vertical walls, filled with SWCNT‐water NF under natural convection is carried out. Due to low concentrations of SWCNT in water, single phase flow is assumed. Velocity and temperature distributions are obtained as solutions to the energy and Navier–Stoke's equations. A comparison of the temperature and velocity profile has been represented by simulating the system over a range of Rayleigh numbers. [ABSTRACT FROM AUTHOR]

The authors report Myxobacteria virescens (M. virescens) mediated synthesis of silver nanoparticles (AgNPs) and its efficacy against Staphylococcus aureus (ATCC‐33591), Salmonella typhi (ATCC‐51812), Escherichia coli (E. coli) (ATCC‐14948), Klebsiella pneumoniae (MTCC‐4030) and Pseudomonas aeruginosa (MTCC‐4673). The organism exhibiting resistance to various antibiotics showed remarkable sensitivity, when used in combination of antibiotics and AgNPs. Antimicrobial property of AgNPs is playing a significant role in medicine and food storage. In this study, they have used M. virescens for the synthesis of AgNPs, which were characterised by using UV‐Vis spectrophotometer, nano‐particles tracking and analysis, zeta potential, Fourier transform infrared spectroscopy, X‐ray diffraction and transmission electron microscopy. Synthesised AgNPs were impregnated into paper by three different methods, i.e. glass rod method (without binder), glass rod method (with binder) and direct synthesis of AgNPs on paper. Nanoparticles synthesis on paper showed the significant antimicrobial activity against Staphylococcus aureus (ATCC‐33591), Salmonella typhi (ATCC‐51812), E. coli (ATCC‐14948), Klebsiella pneumoniae (MTCC‐4030) and Pseudomonas aeruginosa (MTCC‐4673). Paper impregnated with AgNPs was used for wrapping of fruits (apples) which increases their shelf life up to 15 days. This study demonstrates a new method for wrapping of fruits, which increases the shelf life of apples. [ABSTRACT FROM AUTHOR]

To circumvent the bottlenecks of non-flexibility, low sensitivity, and narrow workable detection range of conventional biosensors for biological molecule detection (e.g., dopamine (DA) secreted by living cells), a new hybrid flexible electrochemical biosensor has been created by decorating closely packed dendritic Pt nanoparticles (NPs) on freestanding graphene paper. This innovative structural integration of ultrathin graphene paper and uniform 2D arrays of dendritic NPs by tailored wet chemical synthesis has been achieved by a modular strategy through a facile and delicately controlled oil-water interfacial assembly method, whereby the uniform distribution of catalytic dendritic NPs on the graphene paper is maximized. In this way, the performance is improved by several orders of magnitude. The developed hybrid electrode shows a high sensitivity of 2 μA cm−2 μ m−1, up to about 33 times higher than those of conventional sensors, a low detection limit of 5 n m, and a wide linear range of 87 n m to 100 μ m. These combined features enable the ultrasensitive detection of DA released from pheochromocytoma (PC 12) cells. The unique features of this flexible sensor can be attributed to the well-tailored uniform 2D array of dendritic Pt NPs and the modular electrode assembly at the oil-water interface. Its excellent performance holds much promise for the future development of optimized flexible electrochemical sensors for a diverse range of electroactive molecules to better serve society. [ABSTRACT FROM AUTHOR]

This paper describes how moiré plasmonic nanoparticle lattices can exhibit lasing action over a broad wavelength and wavevector range. Moiré nanolithography is combined with the PEEL (Photolithography, Etching, Electron‐beam deposition, and Lift‐off) process to fabricate in‐plane incommensurate lattices with optical properties beyond the restricted geometries of Bravais lattices. Because of increased rotational symmetry, moiré lattices support a larger number of transverse electric and transverse magnetic modes relative to their periodic base lattices. It is found that multidirectional lasing characteristics can be predicted by the symmetry of the moiré reciprocal lattice. Incommensurate moiré plasmonic lattices combine advantages of the dense band structures observed in aperiodic lattices with that of predicted modes in Bravais lattices for light‐based technologies in coherent light sources and multiplexed data transfer. [ABSTRACT FROM AUTHOR]

One of the important research components of photocatalytic research is the development of new photocatalysts, and recent studies have shown the rise of borate‐type photocatalysts. This paper focuses on the photoreduction of potassium dichromate and the photodegradation of rhodamine B by two borate composites under simulated sunlight. A coral‐like borate was obtained by sol‐gel preparation and then assembled by photodeposition with Pt nanoparticles dots or CuO particles to obtain the new composites with excellent performance. The kinetic constants of photocatalytic properties of 2 %Pt/Gd0.85Ce0.15B5O9 and 2.5 %CuO/Gd0.90Ce0.10B5O9 samples in the reduction and degradation reactions are 0.0050 min−1 and 0.0150 min−1, which are 25 and 4.2 times of the intrinsic GdB5O9 sample respectively. The results of the study indicate the research promise of developing new visible photocatalysts based on borates, especially for photocatalytic applications for pollutant removal. [ABSTRACT FROM AUTHOR]

Lipid nanoparticles (LNPs) exhibit remarkable mRNA delivery efficiency, yet their majority accumulate in the liver or spleen after injection. Tissue‐specific mRNA delivery can be achieved through modulating LNP properties, such as tuning PEGylation or varying lipid components systematically. In this paper, a streamlined method is used for incorporating tumor‐targeting peptides into the LNPs; the programmed death ligand 1 (PD‐L1) binding peptides are conjugated to PEGylated lipids via a copper‐free click reaction, and directly incorporated into the LNP composition (Pep LNPs). Notably, Pep LNPs display robust interaction with PD‐L1 proteins, which leads to the uptake of LNPs into PD‐L1 overexpressing cancer cells both in vitro and in vivo. To evaluate anticancer immunotherapy mediated by restoring tumor suppressor, mRNA encoding phosphatase and tensin homolog (PTEN) is delivered via Pep LNPs to PTEN‐deficient triple‐negative breast cancers (TNBCs). Pep LNPs loaded with PTEN mRNA specifically promotes autophagy‐mediated immunogenic cell death in 4T1 tumors, resulting in effective anticancer immune responses. This study highlights the potential of tumor‐targeted LNPs for mRNA‐based cancer therapy. [ABSTRACT FROM AUTHOR]

Tumor immunotherapy, represented by immune checkpoint blocking and chimeric antigen receptor (CAR) T cell therapy, has achieved promising results in clinical applications. However, it faces challenges that hinder its further development, such as limited response rates and poor tumor permeability. The efficiency of tumor immunotherapy is also closely linked to the structure and function of the immune microenvironment where the tumor resides. Recently, nanoparticle‐based tumor immune microenvironment (TIME) modulation strategies have attracted a great deal of attention in cancer immunotherapy. This is primarily due to the distinctive physical characteristics of nanoparticles, which enable them to effectively infiltrate the TIME and selectively modulate its key constituents. This paper reviews recent advances in nanoparticle engineering to improve anti‐cancer immunotherapy. Emerging nanoparticle‐based approaches for modulating immune cells, tumor stroma, cytokines and immune checkpoints are discussed, aiming to overcome current challenges in the clinic. In addition, integrating immunotherapy with various treatment modalities such as chemotherapy and photodynamic therapy can be facilitated through the utilization of nanoparticles, thereby enhancing the efficacy of cancer treatment. The future challenges and opportunities of using nanomaterials to reeducate the suppressive immune microenvironment of tumors are also discussed, with the aim of anticipating further advancements in this growing field. [ABSTRACT FROM AUTHOR]

In this paper, a new scheme for generating a wide gamut of structural colors on the thin‐film‐stack‐based (TFSB) substrates is proposed. The TFSB surfaces consist of titanium/random gold nanoparticles (AuNPs) and titanium/ random gold and copper nanoparticles (Au+CuNPs), which can trigger more resonance absorption and widen the color gamut. The electric fields in two designed structures are simulated, and the results showed that the random distribution of AuNPs and Au+CuNPs enhance the uniform local surface plasmon resonance (LSPR) response. This enhancement is crucial in broadening the coverage of the reflection spectrum, which enables the generation of a wide range of colors, including green and red. The influence of laser parameters on the color of TFSB substrates and tested their durability in terms of time is analyzed. Finally, a color palette and made structural color patterns on TFSB by nanosecond pulsed laser are prepared. The proposed new scheme can be easily fabricated by magnetron sputtering without requiring additional procedures, which can open new perspectives in plasmonic colors. This work demonstrates that the promising potential of methods in creating a wide color gamut on metallic surfaces. Additionally, it serves as a means to store information for the preservation and protection of traditional cultures. [ABSTRACT FROM AUTHOR]

A potential anode material for lithium‐ion batteries (LIBs), Co3O4 has been widely considered by many scholars because of its excellent properties in terms of electrochemical characteristics and theoretical specific capacity. However, according to the existing research results, we found that the improvement of the electrochemical performance of Co3O4 has encountered a bottleneck because its intrinsic conductivity is not high enough, and more importantly, the volume expansion is too significant during the charge and discharge process, which leads to the material structure breaking. Therefore, this paper proposes a simple and scalable solvothermal and subsequent calcination method to prepare Co3O4 and reduced graphene oxide (RGO) composite nanoparticles with superior microstructures, and their morphological and electrochemical properties were investigated at different calcination temperatures. As a high‐performance anode material for lithium‐ion batteries, the Co3O4/RGO nanoparticles obtained at 550 °C exhibited terrific initial discharge capacity of 1714.2 mAh g−1, the reversible specific capacity of 1191.9 mAh g−1 with quality coulombic efficiency 98.17 % at 0.5 A g−1 after 100 cycles and extraordinary rate performance (907.6 mAh g−1 with a coulombic efficiency of 99.2 % at 2 A g−1). The facile synthesis method and excellent findings have led to better application prospects for Co3O4/RGO nanoparticles. [ABSTRACT FROM AUTHOR]

The capacity of Ag nanoparticles to destroy various micro‐organisms makes it one of the most powerful antimicrobial agents, an attractive feature against antibiotic resistant bacteria. Here, a simple method to develop coating of colloidal silver on paper using a biological method is presented. The coated paper was studied by scanning electron microscopy, X‐ray diffraction technique and atomic absorption spectroscopy. The antibacterial activity of the coated paper against Escherichia coli and Staphylococcus aureus was measured by agar diffusion method. This study shows the potential use of the coated paper as a food antimicrobial packing material for longer shelf life. [ABSTRACT FROM AUTHOR]

In this work, a mediator-less and compartment-less glucose/air enzymatic biofuel cell (BFC) was introduced into microfluidic paper-based analytical devices (μ-PADs) with gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs)-modified paper electrode as the anodic and cathodic substrate, respectively, to implement self-powered, sensitive, low-cost and simple DNA detection. As a further development of the analytical equipment, an all-solid-state paper supercapacitor (PS) was designed and integrated into the BFC for current amplification, and a terminal digital multi-meter detector (DMM) was introduced for the current detection. A highly sensitive DNA sensor was fabricated by covalently immobilizing the capture DNA in the AuNPs-modified anode. The nanoporous gold conjugated with bienzymes, glucose oxidase and horseradish peroxidase, which were used as electrochemical labels. The electrons generated at the anode flow through an external circuit to the PtNPs-modified cathode that catalyzed the reduction of oxygen with the participation of protons. In addition, the generated current could be collected and stored by the PS. After that, the PS was automatically shorted under the control of a switch to output an instantaneously amplified current, which could be sensitively detected by the terminal DMM. At the optimal conditions, the paper-based analytical platform can detect DNA at the femtomole level. This approach also shows excellent specificity toward single nucleotide mismatches. [ABSTRACT FROM AUTHOR]

The fabrication, characterization, and applications of paper‐based screen‐printed carbon electrodes (SPCE) are discussed. In particular, microscopy images of the working electrode surface show a reproducible 3D pattern that enhances the performance of the device compared to that of a polyester‐based SPCE. Gold nanoparticles and CdSe@ZnS quantum dots are detected using different electrochemical techniques. [ABSTRACT FROM AUTHOR]

A facile photoreduction strategy to attach silver nanoparticles on filter paper (AgNPs@FP) to form surface-enhanced Raman scattering (SERS) substrate array was proposed and examined. As prepared, SERS substrate array was applied to detect low concentration of adenine and other nucleobases in aqueous solutions. In addition, the formed SERS substrate array allows mass analysis of aqueous samples with a requirement of only 10 μL in sample volume. To optimize and understand the parameters in preparations, factors such as the concentrations of citrate and silver nitrate, photoreduction time, and concentration of sodium hydroxide were varied and examined. Para-nitrothiophenol was used as a Raman probe molecule and scanning electron microscope (SEM) images of the substrates were used to explore the influences of experimental factors in the preparation of SERS array. Results indicated that silver ions could be effectively reduced and deposited in/on filter paper with the presence of citrate. The formed AgNPs@FP exhibits a three-dimensional structure as the particles formed on and beneath the surface of the cellulosic fibers could be observed. Deposition of analyte on restricted substrate array rendered reproducible results and the spot-to-spot SERS intensity varied within 8%. At optimal conditions, the substrate enhancement factor approached 107. We demonstrated that the filter paper-based SERS substrates can be used as a suitable tool for biological analysis, and a limit of detection better than 160 nM was obtained in detection of adenine molecules in aqueous solutions with a linear range up to 20 μM. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Palladium nanoparticles dispersed in ammonium salts of hyperbranched polystyrenes are adhesively immobilized on the surface of cotton or filter papers by simply heating with dicarboxylic acids or halide anions. The resulting Pd@cotton and Pd@filter paper behave as reusable catalysts; in particular, Pd@filter paper is useful as catalyst for application to sequential cross-coupling and hydrogenation reactions to produce several different products with just one piece of the paper catalyst. [ABSTRACT FROM AUTHOR]

The novel two–dimensional MXene material Ti3C2Tx has the advantages of a large specific surface area, adjustable band gap, good electrical conductivity, and high stability. However, the precipitation of hydrogen via electrolytic water splitting over Ti3C2Tx has unacceptably slow kinetics. In this paper, Co nanoparticles were incorporated on the Ti3C2TxMXene surface via electrostatic adsorption by utilizing the intrinsic MXene defects generated during the etching process. Next, a Fe−Co alloy structure was also constructed on the Ti3C2TxMXenesurface by wet chemical impregnation method using the principle of galvanic coupling substitution. The prepared catalyst had an overpotential of 118 mV at a current density of 10 mA‐cm−2 and a Tafel slope of 97.56 mV dec−1. The Fe−Co alloy structure accelerated the kinetic hydrogen precipitation step, and Fe−Co/Ti3C2Txshowed excellent stability when used in a water electrolysis process for 11 h. This work offers a promising strategy for the synthesis of intrinsically defective synthetic alloy MXene structures. [ABSTRACT FROM AUTHOR]

Poly(ionic liquid) (PIL)‐based porous membranes are extensively investigated as soft polymer actuators. While PILs have shown significant advancements in membrane fabrication and stabilization of metal nanoparticles (MNPs), research on integrating MNPs into porous membranes to achieve actuation behavior under multiple stimuli is limited. Herein, this work presents a new paradigm for designing a porous PIL‐polyacrylic acid (PAA) membrane with a distinct MNP gradient via a top‐bottom diffusion approach involving a metal salt precursor solution and NaBH4 as a reducing agent. The strong binding sites provided by PILs, combined with the gradient distribution of ‐COO− groups across the membrane cross‐section, play a significant role in controlling the MNPs' gradient distribution. Interestingly, the MNPs within the membrane display excellent catalytic activity in exothermic reactions such as H2O2 decomposition, dissipating uneven heat that quickly permeates the membrane network. This induces asymmetrical swelling of polymer chains, resulting in rapid membrane bending. Furthermore, such MNP‐loaded membrane could serve as a portable test paper for visually monitoring H2O2. This advancement paves the way for the development of intricate smart actuation materials and expands their practical applications in various real‐life scenarios. [ABSTRACT FROM AUTHOR]

The paper reports on the synthesis and evaluation of photochemical properties of gold nanorods (Au−NRs) coated with PEG with a thiol (−SH) group or SiO2 and their physical mixtures with pheophorbide a. Also biological activity of these systems was tested in photodynamic therapy directed towards Staphylococcus aureus. The potential additive effect between differently functionalized Au−NRs and the dye pheophorbide a was also studied. The efficiency of singlet oxygen generation varied considerably depending on the type of PEG polymer used for coating NRs and was the highest, of 65%, for the polymer PEG (10k) and the Au−NRs concentration of (1.33×10−11 M). For the other studied PEGs (2k, 5k) and the same concentration of NRs, a decrease in the singlet oxygen generation efficiency was observed. The most effective against Gram‐positive bacteria were the mixtures of PEG‐coated Au−NRs with pheophorbide a, exposed to irradiation at 405 nm and 660 nm, which provided a >5.8 log reduction in the bacteria growth. However, no strong bactericidal effect was noted in the case of irradiation with 525 nm. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have shown inhibitory capabilities and its use in battling viral infections are strengthened by its potent antibacterial activity. Notably, since it directly affects antiviral efficacy, the proper choice of synthesis process for making silver nanoparticles is a vital element to be taken into consideration. The synthesis of silver nanoparticles for the treatment of viral and bacterial infections involves creating silver particles at the nanoscale with unique antimicrobial properties. Various methods exist for synthesizing silver nanoparticles, including chemical reduction, green synthesis, and physical methods. Chemical reduction involves using reducing agents to convert silver ions into silver nanoparticles. Green synthesis employs reducing agents in an environmentally friendly manner. Physical methods rely on techniques such as laser ablation or thermal evaporation to produce silver nanoparticles. In order to provide technological guidance for choosing antiviral silver nanoparticle manufacturing methods, this paper introduces and explores alternative synthesis methods for creating silver nanoparticles. [ABSTRACT FROM AUTHOR]

Lipid nanoparticles (LNPs) are biocompatible drug delivery systems that have found numerous applications in medicine. Their versatile nature enables the encapsulation and targeting of various types of medically relevant molecular cargo, including oligonucleotides, proteins, and small molecules for the treatment of diseases, such as cancer. Cancers that form solid tumors are particularly relevant for LNP-based therapeutics due to the enhanced permeation and retention effect that allows nanoparticles to accumulate within the tumor tissue. Additionally, LNPs can be formulated for both locoregional and systemic delivery depending on the tumor type and stage. To date, LNPs have been used extensively in the clinic to reduce systemic toxicity and improve outcomes in cancer patients by encapsulating chemotherapeutic drugs. Next-generation lipid nanoparticles are currently being developed to expand their use in gene therapy and immunotherapy, as well as to enable the co-encapsulation of multiple drugs in a single system. Other developments include the design of targeted LNPs to specific cells and tissues, and triggerable release systems to control cargo delivery at the tumor site. This review paper highlights recent developments in LNP drug delivery formulations and focuses on the treatment of solid tumors, while also discussing some of their current translational limitations and potential opportunities in the field. [ABSTRACT FROM AUTHOR]

Gallic acid is a renewable plant phenolic resource, and the polyphenolic bio‐based epoxy resin prepared from it can be used as a substitute for bisphenol A epoxy resin in certain fields. However, bio‐based epoxy resins used in the field of high‐performance composite material matrices often require modification. In this paper, firstly, γ‐(2,3‐epoxypropoxy)propyl trimethoxysilane (KH560) was used as the raw material to prepare epoxy‐based cage silsesquioxanes (E‐POSS). Then, E‐POSS was grafted onto γ‐aminopropyltriethoxysilane (KH550) modified halloysite nanotubes (m‐HNTs) to prepare a novel hybrid nanoparticle HNTs‐e‐POSS. Experimental analysis shows that ring opening reactions of amino and epoxy groups can occur between m‐HNTs and E‐POSS, forming a hybrid nanoparticle system of POSS aggregates on the surface of HNTs. Bio‐based nanocomposites were prepared by adding different mass fractions of hybrid nanoparticles HNTs‐e‐POSS into polyphenol type gallic acid epoxy resin matrix (GAER) and using methyltetrahydrophthalic anhydride as curing agent. The properties and micromorphology of the composite were analyzed and characterized. The research showed that with the addition of HNTs‐e‐POSS nanoparticles, the strength and toughness of the composite resin system show a pattern of first increasing and then decreasing, while the storage modulus(E′), glass transition temperature (Tg), and thermal stability of the composite material increased. Mechanical performance analysis shows that the introduction of 0.5 wt% HNTs‐e‐POSS would increase the tensile strength of the composite by 25.46%, while adding 0.75 wt% HNTs‐e‐POSS can increase the impact strength by 15%. The E′(30°C) increased by 24.2% and Tg increased by 7.7°C when the HNTs‐e‐POSS addition was 0.25 wt%. Highlights: Prepared hybrid nanoparticle HNTs‐e‐POSS by grafting POSS onto the HNTs surface.Application of HNTs‐e‐POSS in modification of bio‐based gallic acid epoxy resin.HNTs‐e‐POSS can co‐cured with epoxy matrix to increase the crosslinking degree.The strength, toughness, and modulus of gallic acid epoxy resin are improved.Tg and thermal stability of gallic acid epoxy resin are enhanced. [ABSTRACT FROM AUTHOR]

This study investigates the unsteady Maxwell nanofluid flow past a stretching surface, embedded in a porous medium, in the presence of magnetic field and thermal radiation effects. Polydimethylsiloxane (PDMS) is considered as a Maxwell base fluid and graphene is taken as nanoparticle to form the nanofluid. It is a well‐reported fact in the literature (Boland et al. Science, 354(2016)1257) that viscous graphene polymers can be used to make sensitive electromechanical sensors, thereby setting the direction and incentive for the study of graphene–PDMS nanofluid. In this paper, we have implemented the Navier's slip boundary condition at the nanofluid‐surface interface. Entropy analysis for the energy efficiency of the system in terms of the Bejan number is carried out extensively. By employing suitable similarity transformations, the set of partial differential equations has been transformed into a set of ordinary differential equations. The transformed equations are solved by the homotopy analysis method (HAM). The nanofluid velocity, temperature, skin‐friction coefficient, and heat transfer rate are analyzed in this paper under several regulatory physical parameters. The findings show that the rise in time relaxation parameter has adverse effects on nanofluid velocity but enhances the entropy generation in the system. The heat transfer rate decreases with an enhancement of the Deborah number but increases with a rise in the nanoparticle volume fraction. The Bejan number shows increasing trend with an enhancement of unsteady parameter, nanoparticle volume fraction, and porous permeability parameter. This study bears the potential application in powder technology, plastic extrusion process, as well as in bio‐engineering. [ABSTRACT FROM AUTHOR]