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Agricultural and livestock waste poses a serious concern regarding its management and disposal, as a large sum ends up as solid waste or gets burnt in the field. Therefore, it contributes to air pollution and global warming; thus, different methodologies have been investigated to convert waste into wealth in the form of chemicals, biogas, and raw materials for different industries. In this regard, the electro-methanogenic reactor has shown tremendous enhancement in converting this waste into biogas and bio-fertilizer compared to anaerobic digestion. The improvement is primarily associated with increased hydrogenotrophic methanogens and enriched direct electron transfer in the microorganism matrix. The mini-review aims to provide an overview of existing literature on anaerobic digestion microbial electrolysis cells (AD-MEC) for treating agricultural and livestock waste, offering a promising solution for energy production. It covers technical aspects like pre-treatment methodologies, reactor configuration, and operational procedures. In addition, the economic evaluation of the AD-MEC compared to the AD reactor has been presented to assess the technology's superiority. Furthermore, it identifies potential avenues for future investigations and aims to develop AD-MEC as an efficient and sustainable technology. [Display omitted] • Agricultural and livestock wastes are the most abundant sources of biomass. • Volatile fatty acid buildup limits CH 4 production in anaerobic digestion (AD). • Electromethanogenic process has an advantage over AD for CH 4 production. • Hydrogenotrophic methanogens are prominent in the Electromethanogenic reactors. [ABSTRACT FROM AUTHOR]

In this work, the bandgap of CuO (p-type semiconductor) has been engineered from an indirect bandgap of ∼1 eV to a direct bandgap of 4 eV just by tuning the nanostructure morphology and midgap defect states. The absorption in near-infrared (NIR) and visible regions is ordinarily suppressed by controlling the growth parameters. Considering the increasing scope and demand of varying spectral range (UV-C to NIR) photodetectors, the systematic variation of the available density of states (DOS) at a particular energy level in CuO nanostructures has been utilized to fabricate dual-band (250 nm and 900 nm), broadband (250 nm–900 nm), and UV-C (250 nm) photodetectors. The sensitivity and detectivity of the photodetector for broadband detectors were ∼103 and 2.24 × 1011 Jones for the wavelengths of 900 nm and 122 and 2.74 × 1010 Jones for 250 nm wavelength light, respectively. The UV-C detector showed a sensitivity of 1.8 and a detectivity of 4 × 109 Jones for 250 nm wavelength light. A plausible mechanism for the photoconduction has been proposed for explaining the device operation and the effect of variation in available DOS. The obtained photodetectors are the potential candidates for future optoelectronic applications. [ABSTRACT FROM AUTHOR]

A microbial fuel cell (MFC) is a cutting-edge bioelectrochemical technology, which demonstrates power and other valuables recovery while treating wastewater by cultivating electroactive microbes. However, rampant biofilm growth over the cathode surface of air cathode MFC exacerbates the oxidation-reduction reaction rate, triggering a dip in the overall performance of MFC. In this sense, biosynthesized silver nanoparticles (AgNPs) have garnered a plethora of potential applications as cathode catalysts as well as anti-biofouling agent for MFCs without harming nature. The MFC equipped with the mixture of aloe vera and algae (@5 mg/cm2) synthesized AgNPs on cathode generated a maximum power density of 66.5 mW/m2 and chemical oxygen demand removal efficiency of 85.2%, which was ca. 5.6 times and 1.2 times higher compared to control MFC operated without any catalyst on cathode. Thus, this investigation paves the way for using eco-amiable, low-cost bioderived organic compounds to assist MFC in achieving high power output and other valuables with minimal reliance on chemicals. [Display omitted] • Algae-derived silver nanoparticles (AgNP) showed high anti-biofouling activity. • 5 mg/L dosage of aloe vera and algae-derived AgNP (1:1) silenced fungal cell signal. • Alo-Alg-AgNP coated microbial fuel cell (MFC) achieved 66.5 mW/m2 of power density. • Maximum 85.2% COD was removed from the Alo-Alg-AgNPs catalyst coated MFC (MFC-T3). • Coulombic efficiency was 66.5% higher for MFC-T3 in comparison to control MFC. [ABSTRACT FROM AUTHOR]

Optically induced meta-stable states in the semiconductor lattice temporarily change the conductivity which leads to a phenomenon called persistent photo-conductivity (PPC). We report a PPC effect with long retention time of more than 90 h in solution-processed highly transparent CuO thin film. A 254 nm wavelength light source was used to ‘set’ and thermal annealing at 50°C for 10 minutes and NIR illumination was used to reset PPC effect. Activated trap states without any stimulus which are responsible for PPC effect in CuO thin film has, been investigated by performing temperature-dependent I-V characterization. These trapped charges are released either on heating or illumination with NIR light source. Such a long-enduring PPC achieved in low-cost transparent CuO thin film could pave the way for further study of the feasibility of optically defined, transparent electronics. [ABSTRACT FROM AUTHOR]

Discharge of endocrine-disrupting compounds such as methylparaben (MePa) into natural water bodies deteriorates the aquatic ecosystem. In this regard, electrochemical oxidation (EO) and electro-Fenton (EF) processes are acknowledged as effective methods to eliminate biorecalcitrant compounds from different wastewater matrices. In these systems, the H 2 O 2 -producing ability of carbon-based cathodes is put to advantage for producing homogenous hydroxyl radicals by simulating Fenton's reaction, which dramatically augments the contaminant removal efficiency. However, commercial carbon based cathodes are not economically affordable, especially for voluminous treatment. Hence in the present work, waste-derived carbonised coconut shell (CCS) monolith was employed as a cathode in EO and EF treatment of MePa. Almost the entire MePa with initial concentration of 10 mg/L was removed in 60 min by EO and 45 min by EF process at neutral pH, applied current density of 7.5 mA/cm2, NaCl concentration of 1.0 g/L and 10 mg/L of Fe 2 O 3 dosing. The MePa removal efficiency of the CCS cathode-fitted system after 60 min was better than the commercial graphite plate and Ti-based mixed metal oxide employing system due to higher H 2 O 2 electrosynthesis (H 2 O 2 = 9.0 ± 0.6 mg/L after 60 min). Moreover, the same setup was used for treating 10 mg/L of MePa-spiked real sewage and demonstrated MePa and total organic carbon removal efficiency of 80.16 ± 2.31% and 37.42 ± 3.50%, respectively, in 45 min. Further, the CCS-mediated EF treatment achieved >90% removal of MePa for eight continuous batch cycles and recorded a current density drop of just 0.23% per cycle. The degradation pathway and toxicity assessment of the intermediates using the Ecological Structure Activity Relationships (ECOSAR) tool supported the eco-friendliness of the current treatment scheme. [Display omitted] • Coconut shell-derived carbonised carbon monolith utilised as a binder-free cathode. • Carbon monolith facilitated electrochemical advanced oxidation of methylparaben. • Carbonised coconut shell (CCS) cathode outperformed graphite plate and Ti-cathodes. • CCS cathode was effective in degrading 10 mg/L of methylparaben from wastewater. • Methylparaben degraded to non-toxic intermediates and ultimately mineralised. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbial electrochemical technologies (METs) for carbon capture have been reviewed. • Engineered nanomaterials (ENMs) boost the performance of METs. • The ENM increases algal growth by accelerating the rate of carbon capture. • The ENMs improve electroactive biofilm growth and electron transfer. • The ENMs have anti-biofouling and augmenting proton conductivity properties. The mounting threat of global warming, fuelled by industrialization and anthropogenic activities, is undeniable. In 2017, atmospheric carbon dioxide (CO 2), the primary greenhouse gas, exceeded 410 ppm for the first time. Shockingly, on April 28, 2023, this figure surged even higher, reaching an alarming 425 ppm. Even though extensive research has been conducted on developing efficient carbon capture and storage technologies, most suffer from high costs, short lifespans, and significant environmental impacts. Recently, the use of engineered nanomaterials (ENM), particularly in microbial electrochemical technologies (METs), has gained momentum owing to their appropriate physicochemical properties and catalytic activity. By implementing ENM, the MET variants like microbial electrosynthesis (MES) and photosynthetic microbial fuel cells (pMFC) can enhance carbon capture efficiency with simultaneous bioenergy production and wastewater treatment. This review provides an overview of ENMs' role in carbon capture within MES and pMFC, highlighting advancements and charting future research directions. [ABSTRACT FROM AUTHOR]

Indoor photovoltaics (IPVs) using low‐toxicity bismuth‐based perovskite‐inspired materials (PIMs) can potentially power the growing number of Internet of Things devices sustainably. However, modest indoor power conversion efficiency (PCE) values are reported due to intrinsic limitations of PIMs, particularly regarding charge carrier separation and transport. Herein, polycrystalline Cs₂AgBi₂I₉ thin films are developed with high phase purity and study their fundamental structural and photophysical properties. The comprehensive experimental and computational study reveals unique optoelectronic properties of Cs₂AgBi₂I₉ compared to other bismuth‐containing PIMs, including weak electron‐phonon coupling and low exciton binding energy (40 meV). This study also demonstrates the feasibility of large and highly mobile polaron formation in Cs₂AgBi₂I₉, supported by the observation of a phonon bottleneck and a delayed hot carrier lifetime of over 200 ps, which suggests enhanced defect tolerance and transport properties. Motivated by the suitable bandgap of this absorber (1.78 eV), the first Cs₂AgBi₂I₉‐based IPVs are developed, achieving a PCE of ≈8% at 1000 lux. Notably, the devices maintain high performance across various indoor environments with white LED color temperatures ranging from 2700 to 6500 K. The calculated theoretical PCE limit of >40% and the promising operational stability position Cs₂AgBi₂I₉ as one of the most intriguing candidates for sustainable IPVs. [ABSTRACT FROM AUTHOR]

Background: Acute appendicitis is one of the most commonly abdominal emergencies in surgery. Several scoring systems developed on the basis of clinical history and physical examination and ultrasound imaging to arrive at a diagnosis but still acute appendicitis or appendicular perforation cannot be predicted by any specific markers. This study was to establish correlation between raise of serum bilirubin and severity of appendicitis and its specificity in diagnosing it. Materials & Methods: This was a prospective observational study carried out in the Department of General Surgery, Kalinga Institute of Medical Sciences. Total 90 patients were selected for the study with thorough clinical assessment, laboratory investigations, ultrasound findings. After confirming the diagnosis of Acute Appendicitis, the patients had undergone operative intervention. In all patient's liver function, serum bilirubin along with liver enzyme assay was done and the findings were correlated with severity of appendicitis and its complications. Results: Out of total 90 patients 58 were male and 32 were female with mean age of the patients participated is 32.34 years. Mean total serum bilirubin of the patients with diagnosis of acute appendicitis is 0.61mg/dl with a standard deviation of 0.34 and those with diagnosis of Appendicular perforation is 1.41 mg/dl with a standard deviation of 0.90. Mean SGOT and SGPT have mildly raised with perforated appendicitis. Conclusion: Study conducted suggested that there is a significant raise of serum bilirubin levels in the cases of severe acute appendicitis. Along with clinical and radio imaging, study of serum bilirubin levels pre-operatively will be an effective indicator in cases of acute appendicitis in grading the severity of appendicitis [ABSTRACT FROM AUTHOR]