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The metaplastic breast carcinoma is a rare malignancy with an incidence of 5% of all breast tumors. Metaplastic carcinoma of the breast with mesenchymal differentiation (MCMD), previously known as carcinosarcoma, is a very rare and aggressive tumor that has been recently classified as a subtype of metaplastic breast carcinoma. It accounts for 0.08%–0.2% of all breast cancers, with only a few cases reported in the literature. Metaplastic breast carcinoma most often affects women over 50 years of age, with an average age between 55 and 60 years. We report three cases of metaplastic breast carcinoma with mesenchymal differentiation presented at our hospital. Patients were in their 4th decade. All patients presented with a fast-growing large mass and were treated surgically (mastectomy), with the final histopathological diagnosis of MCMD. [ABSTRACT FROM AUTHOR]

Introduction: In India, prostate carcinoma is the fifth most common cause of carcinoma in men, and the fourth in cancer mortality. Incidence of prostate malignancy is increasing in India by one percent every year. Prostate carcinoma is graded using the Gleason scoring system. The Gleason score is very useful for predicting the prognosis of prostate carcinoma. The collaborative use of clinical features, combined with the size of the prostate, prostate-specific antigen levels, and histopathological features helps in making an accurate and early diagnosis of the patients. Material and Method: This present prospective study included all histologically proven cases of prostate carcinoma in the Department of Pathology, Guru Gobind Singh Medical Hospital over a period of one year. A detailed histopathological examination of the H and E stained sections is carried out under light microscope including histological typing, Gleason scoring and grading. The Gleason grade was correlated with serum PSA levels. Results: Out of 80 cases, 28 (35%) were reported as Gleason grade group 3 with a Gleason score of 7 (4 + 3). 12 cases (15%) showed a Gleason grade group 2 with a Gleason score of 7 (3 + 4). Grade group 4 (Gleason score 8) and grade group 5 were observed in 22 cases (27.5%) and 18 cases (22.5%), respectively. Whereas, no case of Gleason grade group 1 with Gleason score of 6 (3 + 3) was seen. Conclusion: Gleason's Group Grade 3 outnumbered all the group grades, contributing 35% (28 cases) of the total cases of prostatic adenocarcinoma. Serum PSA levels were raised (>10 ng/ml) in 100% of cases. Henceforth, it signifies the importance of serum PSA levels in prostate carcinoma. Lymphovascular invasion was associated with higher group grade of prostatic adenocarcinoma. [ABSTRACT FROM AUTHOR]

Using heterogeneous photocatalysts for harvesting sunlight and converting it for water remediation and splitting are promising to mitigate the possible crisis of environment and energy. Among various composites, the MoS2‐based heterostructures and Ni‐based systems exhibit unique electronic, optical properties and redox capabilities, enabling their roles as photocatalysts. Herein, the impacts of chemical environments on the Ni electronic structures within the MoS2‐Ag‐Ni ternary systems are studied via X‐ray photoemission electron spectroscopy (X‐PEEM). Ni nanoparticles with two different sizes of 70 and 200 nm were loaded to MoS2 flakes with silver buffers as bridges. Heterostructures with a nominal mol percentage of (MoS2)77Ag3.7Ni19.3 were synthesized through an ultrasound‐assisted wet method. The oxidation states and various interfacial interactions of Ni with MoS2 in MoS2‐Ag‐Ni ternary composite are spectromicroscopically determined, combining the X‐ray absorption spectroscopy near Ni L‐edges and the imaging capability of the X‐PEEM. Results showed that Ni mainly retrains its chemical states of metal and native oxidizations without observable electronic features subjected to bonding with the sulfur from the MoS2 flakes. The charge migration channel set up by the Ag buffer thus contributes to electron–hole migrations that facilitate the photocatalytic performance of the ternary system eventually. [ABSTRACT FROM AUTHOR]

[Display omitted] • X-PEEM and Raman mapping are used to probe interfaces in Ni-Ag-MoS 2 heterostructure. • Higher H 2 yield of Ni-Ag-MoS 2 evidence successful bonding of Ni, Ag and MoS 2. • Downshift due to charge injection and upshift due to strain is noted in phonons. • Ag intercalated MoS 2 , its non-uniform growth, and intimate contact with MoS 2 is noted. • Electronic coupling and strain can tune the electromechanical properties of MoS 2. Despite the boom in catalytic response via constructing interfaces, understanding interfaces' interaction in heterostructures is still a paradox. In this work, the interaction of Ni with MoS 2 in Ni-Ag-MoS 2 heterostructure are unveiled through synchrotron X-PEEM and what's more, the missing interaction mechanism at the Ag-MoS 2 interface is probed via Raman mapping. The observed competition between the downshift of the E 2g 1 and A 1g modes due to charge carrier injection and the upshift of the E 2g 1 and A 1g modes due to compressive strain during reverse laser power experiment is assigned to the non-uniform growth of Ag nanoparticles, their intimate contact with MoS 2 , and Ag intercalated layered MoS 2. The substantial improvement of the H 2 yield of the Ni-Ag-MoS 2 (∼55 μmol h−1 g−1) over the pristine MoS 2 and the binary Ag-MoS 2 evidence successful bonding of Ni, Ag and MoS 2. This study highlights the importance of considering both electronic coupling and strain to optically tune electromechanical properties of MoS 2. [ABSTRACT FROM AUTHOR]

Intriguing spherical conformation of polyvinyl pyrrolidone (PVP) embedded with CdS nanocrystals in CdS-PVP nanocomposites grown via facile chemical bath deposition is probed using simultaneous Raman and AFM mapping. Observance of isolated or coagulated PVP spheres embedded with CdS nanocrystals at room temperature (RT) due to polymer collapse or clouding, respectively, is attributed to relative variation in Cd+/PVP concentration in the bath. With an additional external stimulus of temperature (70 °C) and subsequent growth at RT in the same chemical bath, observed only isolated and dimer PVP spheres are ascribed to opening (high temperature) and reformation (RT) of PVP spheres with dominating collapse mechanism of polymer. Formation of dimer PVP sphere due to lock and key binding mechanism is facilitated by the temperature. Transformation of RT grown mixed-phase structure to purely hexagonal phase further confirming the change in conformation of CdS-PVP nanocomposites on the application of an external stimulus. Stronger resonance Raman scattering for CdS nanocrystals embedded in the isolated PVP spheres is attributed to strain-related band gap tuning. The understanding developed of the application of the external stimulus leading to change in polymer conformation can be gainfully used in macromolecular actuators and biomedical field as delivery systems. Application of an external stimulus of temperature and subsequent growth at room temperature led to formation of only isolated and dimer PVP spheres embedded with CdS nanocrystals, wherein formation of dimer PVP spheres happen due to lock and key binding mechanism between two isolated PVP spheres. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chemically and Green synthesized Fe 3 O 4 NPs obtained by a facile hydrothermal method. • Lattice Parameter observed via HR-TEM & XRD (3 1 1) peak matches well with standard one. • Comparative Antimicrobial studies of chemically & green synthesized Fe 3 O 4 NPs explored. • Antibacterial studies of Green synthesized NPs showed effectiveness against Xcc. • Antifungal studies shows potential of synthesized Fe 3 O 4 NPs even at 0.125 mg/ml conc. The present study explores the antimicrobial properties of Fe 3 O 4 nanoparticles synthesized by chemical and green routes using hydrothermal methods. In this respect, the neem tree (Azadirachta indica) bark extract was used as a green source to utilize the advantage of the phytochemicals present in it. The synthesized nanoparticles (NPs) were characterized by UV–visible spectroscopy, HR-TEM, DLS, XRD and FTIR. The average particle size of chemically synthesized and phytofabricated NPs was ∼ 23 nm and ∼ 6 nm, respectively. FTIR spectra confirmed the presence of different phytochemicals like phenols, amines, aromatic, amides and carboxylic groups in the phytofabricated Fe 3 O 4 NPs. Further, its antibacterial activity was evaluated using the agar well diffusion method against phytopathogens: Xanthomonas campestris pv. campestris Xcc –C7, Bacillus subtilis DTBS-5 and Pseudomonas fluorescens DTPF-3 (PSfl) under in vitro conditions. The antifungal property of NPs was studied by poison food agar assay against mycopathogens, i.e., Fusarium graminearum and Phytophthora spp. The phytofabricated Fe 3 O 4 NPs showed bactericidal action against Xcc and inhibited the fungal growth as well. The outcome of this study will be beneficial for its potential application in the management of bacterial and fungal plant pathogens during crop cultivation in agriculture. [ABSTRACT FROM AUTHOR]

A colourimetric assay for the detection of DNA fragments associated with the oil palm pathogen Ganoderma boninense and other fungi DNA is reported. The assay is based on the aggregation of DNA-nanoparticle conjugates in the presence of complementary DNA from the target organism. Here, various designs of DNA-nanoparticle conjugates were evaluated, and it was found that the best design gave a visually observable colour change with as little as 2 pmol of double-stranded DNA analyte even in the presence of a large excess of a mixture of non-complementary DNA. Overall, this label-free system is rapid, sensitive, selective, simple in design, and easy to carry out. It does not require specialist equipment or specialist training for the interpretation of the results, and therefore has the potential to be deployed for agricultural diagnostics in the field. Development of a colourimetric assay based on DNA-nanoparticle conjugates for the oil palm pathogen Ganoderma boninense. [ABSTRACT FROM AUTHOR]

CdS-PVP nanocomposites grown with various concentrations of Cd + /S − and PVP are studied using Raman and atomic force microscopy mapping on same selected areas. The study shows that CdS nanocrystals are embedded in either a thin-film or spheres of PVP, formation of which depends on relative ratio of Cd + /S − concentration (density of nanocrystals) to PVP. Collapse of PVP from planer matrix to the sphere morphology is correlated with high density of CdS nanocrystals and the attractive interaction between CdS nanocrystals and PVP polymer leading to a co-operative growth mechanism. The understanding developed can be used to control the growth of CdS-PVP nanocomposites with desired properties for optoelectronic device applications. [ABSTRACT FROM AUTHOR]

Correlation between size, bonding of Si and O at the surface/interface of Si nanocrystals and frequency of Si phonons in Si-SiO 2 nanocomposites is established using Raman mapping and X-ray photoelectron spectroscopy. Corroboration of these results with absorption spectroscopy shows that lowering of direct transition of light electron conduction band to heavy hole valence band ∼2.8 and 2.95 eV is a result of the interplay between effect of electron confinement (increases band gap) and oxidation bonding environment at the surface/interface (decreases band gap) of a nanocrystal in Si-SiO 2 nanocomposites. These studies have generated deeper insight into the fundamental understanding of the nanocomposite, which can allow easy optical microscopy monitoring of Si-SiO 2 based device fabrication. [ABSTRACT FROM AUTHOR]

Plexiform Fibrohistiocytic Tumour (PFHT) is an intermediate malignant tumour of soft tissue. It is a rarely metastasising dermal subcutaneous neoplasm. It affects children and young adults. The age range of presentation is from birth to age 77 years. The tumour is most commonly located on the upper extremities, whereas the involvement of the frontal region is rare. The differential diagnosis includes benign fibrous histiocytoma, fibromatosis, giant cell tumour and neurofibroma. Plexiform fibrohistiocytic tumour is a slow-growing mass and which is considered a low grade malignant tumour. Treatment is simple excision. It can exhibit aggressive behaviour and rate of local recurrence is 12-38%. A 45-year-old female was presented with a solid mass on the frontal region of the head which was diagnosed as a plexiform fibrohistiocytic tumour with underlying frontal bone invasion on histopathological examination of an excised mass in the Pathology Department. Plexiform Fibrohistiocytic Tumour (PFHT) is a mesenchymal neoplasm that shows a multinodular growth pattern and which is composed of fibroblasts, histiocyte-like cells and multinucleated osteoclast like giant cells. Clinically, it is usually a slow-growing mass with frequent local recurrence and rare regional lymphatic and systemic metastasis. [ABSTRACT FROM AUTHOR]

Raman and atomic force microscopy (AFM) mapping on the same selected area are used to get unique information about the morphology of Si nanocrystals (NCs) embedded in SiO 2 , which is difficult to obtain by any other conventional technique. The sensitivity of Raman spectroscopy to surface/interface and confinement effects in NCs is effectively used to correlate the Raman intensity profile in Raman mapping with the topography obtained from AFM to understand that Si NCs are clustered in i) smaller clusters (∼100 nm) organized closely in two dimensions (2D) and ii) big (∼2 μm) three dimensional (3D) isolated clusters, although the growth is carried out to be multilayer (Si/SiO 2 ). Raman mapping performed by varying the focal spot along the depth shows stacking of larger (>∼60 Å) to smaller sizes (<∼40 Å) Si NCs from bottom to top for some clusters. To understand the observed morphologies, further study of specially grown Si–SiO 2 nanocomposites is performed, which suggest formation of smaller Si NCs at the top due to annealing at 800 °C in Si rich SiO 2 and possible existence of thermal gradient in an insulating matrix of SiO 2. Larger Si NCs are formed in the laser induced plume (plasma) itself. [ABSTRACT FROM AUTHOR]

Raman spectroscopy/mapping is used to investigate the variation of Si phonon wavenumbers, i.e., lower wavenumber (LW ~ 495-510 cm−1) and higher wavenumber (HW ~ 515-519 cm−1) phonons, observed in Si-SiO2 multilayer nanocomposite (NCp) grown using pulsed laser deposition. Sensitivity of Raman spectroscopy as a local probe to surface/interface is effectively used to show that LW and HW phonons originate at surface (Si-SiO2 interface) and core of Si nanocrystals, respectively. The consistent picture of this understanding is developed using Raman spectroscopy monitored laser heating/annealing and cooling experiment at the site of the desired wavenumber, chosen with the help of Raman mapping. Raman spectra calculations for Si41 cluster with oxygen and hydrogen termination show strong mode at 512 cm−1 for oxygen terminated cluster corresponding to the vibration of surface Si atoms. This supports our attribution of LW phonons to be originating at the Si-SiO2 surface/interface. These results along with XPS show that nature of interface (oxygen bonding) in turn depends on the size of nanocrystals and LW phonons originate at the surface of smaller Si nanocrystals. The understanding developed can conclude the ongoing debate on large variation in Si phonon wavenumbers of Si-SiO2 NCps in the literature. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Nanocomposites of CdS nanocrystals (NCs) embedded in a polyvinyl pyrrolidone are grown using one-step chemical bath deposition technique. While this method eliminates an additional step for the growth of NCs, it also leads to the formation of nearly monodispersive CdS NCs as indicated by absorption, reflection, and photoluminescence spectroscopy. Further, scanning electron microscopy, energy-dispersive spectroscopy, and transmission electron microscopic investigations reveal the formation of nearly monodispersive CdS NCs (~6 to 10 nm) embedded in PVP spheres of sizes ~100 to 600 nm. Systematic study of variation in Cadmium acetate (Cd ion source), Thiourea (S ion source), PVP concentration, deposition time, and heating/cooling cycles elucidates the co-operative growth mechanism for CdS-PVP nanocomposite. The experimental observations of this study are corroborated with existing theoretical simulations for nanocomposite growth, which explicates that collapse of PVP into a sphere is crucial to inclusion of only nearly monodispersive CdS NCs. Important insights obtained from this work give control on the growth of nearly monodispersive CdS NCs embedded in PVP, using a simple and inexpensive growth technique. [ABSTRACT FROM AUTHOR]

Specially designed laser heating experiment along with Raman mapping on Si-SiO2 nanocomposites elucidates the contribution of core and surface/interface in the intermediate frequency range (511-514 cm-1) Si phonons. The contribution of core to surface/interface increases with the size of Si nanocrystal, which itself increases on laser irradiation. Further, it is found that resonance Raman is crucial to the observance of surface/interface phonons and wavelength dependent Raman mapping can be corroborated with band edges observed in absorption spectra. This understanding can be gainfully used to manipulate and characterize Si-SiO2 nanocomposite, simultaneously for photovoltaic device applications. [ABSTRACT FROM AUTHOR]

In this work, the unique plastic deformation behavior of T2 rolled copper foils under ultrasonic impact (UI) and ultrasonic rolling (UR) has been studied systematically. The numerical simulation and test results show that with the decrease of the thickness of copper sheet, the equivalent plastic strain (PEEQ) value and plastic strain εp formed by UI or UR increase exponentially, and its distribution changes from gradient to uniform on the cross section, which is distinctive from the commonly observed gradient structure in ultrasonically treated bulk materials. Correspondingly, characterized by EBSD and TEM, the 100-μm-thick copper foil treated by UR shows the overall strengthening and forming a sub-micron grain structure with significant refinement and uniform distribution on the cross section. The microstructure homogenization of copper foil is attributed to the rigid wall effect facilitating the elastic-plastic stress wave bounce. The exponential increase of PEEQ and εp is explained as that with the decrease of the thickness of ultrasonic object, on the one hand, the acoustic softening and size effect which can reduce the elastic limit of copper foil are enhanced; on the other hand, the plastic deformation mode changes from stress superposition to dynamic impact. Through the establishment of a new theoretical model, the criterion of ultrasonic dynamic impact effect is deduced and verified by experiments. [ABSTRACT FROM AUTHOR]

2D materials have attracted tremendous research interest since the isolation of graphene. Their remarkable optical, electronic, and mechanical properties show that they hold great potential across a range of technological applications. As a result, there is a growing demand for low‐cost, low‐energy, and high‐resolution lithography methods that will enable the integration of 2D materials into complex integrated circuitry, biomedical devices, and in the generation of quantum‐confined nanostructures. Recent advances in scanning probe nanolithography (SPL) techniques for the lithography of 2D materials such as graphene, black phosphorus, molybdenum disulfide, and tungsten diselenide are discussed, including the various physiochemical aspects of subtractive and additive lithography of these materials. Examples of 2D‐material‐based devices fabricated by SPL and their properties are also described. The comparative advantages of the individual SPL techniques are discussed along with the future outlook of SPL for 2D materials. [ABSTRACT FROM AUTHOR]

There is an increasing demand for lithography methods to enable the fabrication of diagnostic devices for the biomedical and agri-food sectors. In this regard, scanning probe lithography methods have emerged as a possible approach for this purpose, as they are not only convenient, robust and accessible, but also enable the deposition of "soft" materials such as complex organic molecules and biomolecules. In this report, the use of polymer pen lithography for the fabrication of DNA oligonucleotide arrays is described, together with the application of the arrays for the sensitive and selective detection of Ganoderma boninense, a fungal pathogen of the oil palm. When used in a sandwich assay format with DNA-conjugated gold nanoparticles, this system is able to generate a visually observable result in the presence of the target DNA. This assay is able to detect as little as 30 ng of Ganoderma-derived DNA without any pre-amplification and without the need for specialist laboratory equipment or training. [ABSTRACT FROM AUTHOR]

Background: This study compared rapid and slow intrathecal fentanyl injection followed by a slow injection of bupivacaine to estimate the duration of postoperative analgesia in lower-segment caesarean sections (LSCS). Methods: The study was performed on 60 parturient aged 18-35 years undergoing LSCS and was divided equally into two groups. Group A (Normal Sequential) received slow sequential intrathecal injections of fentanyl and hyperbaric bupivacaine and Group B (Rapid Sequential) received a rapid intrathecal injection of fentanyl followed by a slow injection of hyperbaric bupivacaine. We compared the duration of postoperative analgesia, time of onset of sensory and motor block attained, the highest level of sensory block attained, duration of motor block, Visual Analogue Scale (VAS) scores, spinal anaesthesia-related complications and haemodynamic parameters between both the groups. Results: The duration of postoperative analgesia was longer (P < 0.001) in group B (3.22 ± 0.66 hrs) as compared to group A (2.53 ± 0.41 hrs.) The onset of sensory block was faster (P < 0.001) in group B (1.01 ± 0.29 min) as compared to group A (1.32 ± 0.08 min). More patients in group B achieved higher levels of sensory blockade as compared to group A (5 patients in group A and 12 patients ofgroup B achieved a sensory block up to the T2 dermatome). VAS scores and the requirement of rescue analgesia were significantly lower (10 in group B and 19 in group A). Conclusion: Rapid sequential intrathecal injection of fentanyl and hyperbaric bupivacaine provided better anaesthesia and postoperative analgesia than the normal group. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalysts were utilized widely for degrading organic pollutants in water using the advanced, environment-friendly, low-cost, and highly efficient photocatalysis technique. There are various complex energy-consuming techniques used for the refinement of wastewater. However, the photocatalysis process is the cleanest technique used for degrading organic pollutants in wastewater into the water; carbon dioxide, other small molecules, and inorganic pollutants were reduced or oxidized into harmless substances. SrTiO 3 nanoparticles (NPs) synthesized by the chemical method are the topic of attention among researchers because of their physical, chemical & photocatalytic properties under sunlight for water purification applications. This paper dealt with the study of The photocatalytic properties of SrTiO 3 and its composites under sunlight irradiation. Here, we evaluated the photodegradation of methyl orange (MO) and methylene blue (MB) pollutants using SrTiO 3 as a photocatalyst for de-ionized (DI) water and hard water, respectively. Later on, the ex-situ decoration of Ag and Au nanoparticles (NPs) on SrTiO 3 NPs results in enhancing the photocatalytic activity of SrTiO 3. This article shows the abnormal behaviour of MO degradation compared to MB dye because there was no degradation of methyl orange for both bare SrTiO 3 and Ag, Au@SrTiO 3 nanocomposites. However, for bare-SrTiO 3 , the photocatalytic degradation of MB dye for de-ionized and hard water was accomplished in 210 min and 300 min, respectively. Here, SrTiO 3 with MB dye shows enhanced photocatalytic activity for de-ionized water than hard water, and thus we determined the degradation of SrTiO 3 nanocomposites with DI water only. While in the case of SrTiO 3 nanocomposites, degradation occurred in 210min for Ag and 180 min for Au in DI water which signifies that Au a better co-catalyst for photodegradation. Although, degradation of MO in both DI water and hard water does not show any photocatalytic activity even in 6 and 7 h, respectively, for bare SrTiO 3 and its nanocomposites. Therefore, it gives an idea about the different behaviour of dyes in photocatalytic degradation of DI and hard water using bare SrTiO 3 and noble metal doped SrTiO 3 as photocatalysts for water remediation applications. At a glimpse, this work focus on the photocatalytic removal of various water pollutants using the efficient noble metal (Au & Ag) doped SrTiO 3 as a photocatalyst and discusses the properties of those materials and also discuss the prospects for the utilization of those photocatalysts in complex form for the wastewater treatment. [Display omitted] • Photocatalytic degradation of MB & MO with SrTiO 3 in DI & hard water under sunlight. • Reported anomalous behaviour of MO dye with SrTiO 3 in DI & hard water. • Degradation of MB with Au & Ag as co-catalyst and SrTiO 3 as photocatalyst. • Reported degradation of MB with SrTiO 3 –Au & SrTiO 3 –Ag in 180 & 210 min. • First reported water pollutant removal with >99% efficiency using SrTiO 3 and Au, Ag. [ABSTRACT FROM AUTHOR]

• Unveiling the role of carbonate in Ni-based core/shell plasmonic photocatalyst. • Revealing amorphous NiCO 3 as an active side for H 2 reduction via DFT calculations. • Enhancing photocatalytic activity by the incorporation of NiO as a middle layer. • Optimizing the photocatalytic performance by post-vacuum annealing thermal treatment. Though carbonates are known for several decades, their role in sun-light driven photocatalysis is still hidden. Herein, carbonate boosted solar water splitting in nickel-based plasmonic hybrid nanostructures is disclosed for the first time via in-situ experiments and density-functional theory (DFT)-based calculations. Ni@NiO/NiCO 3 core@shell (shell consisting of crystalline NiO and amorphous NiCO 3) nanostructure with varying size and compositions are studied for hydrogen production. The visible light absorption at ∼470 nm excludes the possibility of NiO as an active photocatalyst, emphasizing plasmon driven H 2 evolution. Under white light irradiation, higher hydrogen yield of ∼80 µmol/g/h for vacuum annealed sample over pristine (∼50 µmol/g/h) complements the spectroscopic data and DFT results, uncovering amorphous NiCO 3 as an active site for H 2 absorption due to its unique electronic structure. This conclusion also supports the time-resolved photoluminescence results, indicating that the plasmonic electrons originating from Ni are transferred to NiCO 3 via NiO. The H 2 evolution rate can further be enhanced and tuned by the incorporation of NiO between Ni and NiCO 3. [ABSTRACT FROM AUTHOR]

Ensembles of silicon nanoparticles (Si-nps) embedded in SiO2 matrix were grown by alternate ablation of Si and SiO2 targets using KrF excimer laser based pulsed laser deposition (PLD). The sizes of Si-nps (mean size ranging from 1-5 nm) were controlled by varying the ablation time of silicon target. Transmission electron microscopy (TEM) along with selected area electron diffraction (SAED) and Raman spectroscopy were used to confirm the growth of silicon nanoparticles, its size variation with growth time and the crystalline quality of the grown nanoparticles. TEM analysis showed that mean size and size distribution of Si-nps increased with increase in the ablation time of Si target. Intense peaks ~521 cm-1 in Raman analysis showed reasonably good crystalline quality of grown Si-nps. We observed asymmetric broadening of phonon line shapes which also redshift with decreasing size of Si-nps. Photoluminescence (PL) from these samples, obtained at room temperature, was broad band and consisted of three bands in UV and visible range. The intensity of PL band in UV spectral range (peak ~3.2 eV) was strong compared to visible range bands (peaks ~2.95 eV and ~2.55 eV). We observed a small red-shift (~0.07 eV) of peak position of UV range PL with the decrease in the mean sizes of Si-nps, while there was no appreciable size dependent shift of PL peak positions for other bands in the visible range. The width of UV PL band was also found to increase with decrease of Si-nps mean sizes. Based on the above observations of size dependent redshift of UV range PL band together with the PL lifetimes and PL excitation spectroscopy, the origin of UV PL band is attributed to the direct band transition at the Г point of Si band structure. Visible range bands were ascribed as defect related transitions. The weak intensities of PL bands ~2.95 eV and ~2.55 eV suggested that Si nanoparticles grown by PLD were efficiently capped or passivated by SiO2 with low density of surface/interface related defects. [ABSTRACT FROM AUTHOR]

[Display omitted] • The advantages of BMOFs and their composites are summarized and discussed. • BMOFs and their composites exhibit high electro/photoelectrocatalytic properties. • We investigated the current problems and future solutions of BMOFs. • The challenges of BMOFs for electro/photoelectrocatalysts are summarized. • This is the first review dedicated to BMOFs for electro/photoelectrocatalysts. Owing to the growing demand in areas such as energy, environmental science, electro- and photoelectrocatalysis, different reactions such as HER (hydrogen evolution), OER (oxygen evolution), ORR (oxygen reduction), and CO 2 RR (CO 2 reduction) represent attractive strategies to overcome the challenges in sustainable energy conversion and usage. The competition for introducing catalysts with higher performance and cost-efficiency in comparison to the previous systems based on noble metals is one of the most interesting directions in this field. By merging the advantages of inorganic and organic materials, MOFs (metal–organic frameworks) have gained an ample attention as highly versatile electro- and photoelectrocatalytic platforms. This is governed by the intricate features of MOFs including extraordinary surface area, exceptional porosity, tailorable pore size, vast structural and chemical tunability, and pre- and post-synthesis structural modifiability. In contrast to monometallic compounds, bimetallic MOFs (BMOFs) and their composites offer many advantages, including improved electrical conductivity, extended active sites, high charge capacity, and adjustable electrochemical activity. Metal-organic frameworks can also be combined with other electrochemically active materials, resulting in advanced composites with large specific area, increased electrical conductivity, and superiour dispersion. Besides, some BMOFs show an enhanced electrocatalytic activity under light irradiation, thus permitting their application as photoelectrocatalysts. The present review summarizes the state-of-the-art on bimetallic MOFs and derived composites for the main current types of electro- and photoelectrocatalytic applications. The study also aims to highlight the challenges and opportunities in this area, with a focus on future perspectives of such multimetallic compounds and materials, with a particular emphasis in the field of energy and electrophotocatalysis. [ABSTRACT FROM AUTHOR]