Environmental Friendly Technique Research Articles

COMPARATIVE STUDY ON THE USE OF TRADITIONAL, CONVENTIONAL AND ADVANCED METHODOLOGIES FOR SUSTAINABLE AGRICULTURE – A REVIEW

Environmental friendly techniques for elevating soil health includes the use of various organic amendments such as in the form of organic manures, green manures, organic matter in form of leftover straws, bio-fertilizers, composts, and many more. Traditionally the farmers usually preferred to make use of organic manures as they received a by-product from cattle farming. This helped them to maintain soil health sufficiently. However, now with the increase in population and decrease in crop yield, it has been the time to make some efforts to produce as much as sufficient as the food demand. Therefore, the conventional trend developed towards the use of artificial amendments in the form of chemical fertilizers. This improved the crop yield and proved effective to nourish demand. However, this also turned a curse with time by lowering bio geological cycles of soil and so lowering the fertility which indeed made overuse of chemical fertilizers. This has been continued for decades. Momentarily focusing more on crop productivity by supplying nutrients without harming the rhizosphere has been made possible with the help of nano fertilizers. Nanotechnology is the most advanced technology in current research trends. The current review focuses on how effective these methodologies are.

A comprehensive GEP and MEP analysis of a cement-based concrete containing metakaolin

Due to the detrimental environmental consequence of cement formation, studies has concentrated on decreasing the environmental influence and expense of cement containing products. It is crucial to conduct research on the mechanical characteristics of cement additive/replacement products such as metakaolin (MK). To serve the said purpose, the importance of developing predictive machine learning (ML) models is growing as ecological concerns intensify. Since there are few ML approaches for them, it is imperative to develop techniques to improve the mechanical properties of such products. In order to overcome these issues, this research examines ML methods for forecasting the compressive strength (fc') of concrete containing MK. Gene expression programming (GEP) and multigene expression programming (MEP), two distinct ML predictive models, are provided in detail along with the most useful variables, enabling effective analysis and forecasting of the fc' of concrete containing MK. An important component of any prediction or simulation endeavor is model generalization, and the researchers of this study used a data set of MK concrete mechanical properties for this purpose. The database has 405 data points with pertinent model parameters to calculate the fc' of concrete containing MK. Cement, percentage of metakaolin by binder, coarse and fine aggregate by binder, water by binder, coarse aggregates by fine aggregates, percentage of superplasticizer by binder, and age are among the factors in the database that influence concrete's fc' yet still previously infrequently regarded as crucial input attributes. The effectiveness of the models is then examined in order to choose and implement the best predicted model for the mechanical properties of MK-based concrete. According to the findings of this research, the optimal ML algorithms for forecasting MK-based concrete fc' is MEP with R2 value of 0.96. Additionally, the sensitivity analysis shows that water-by-binder, percentage of superplasticizer-by-binder and age have the significant effect on the development of compressive strength of metakaolin based concrete. GEP and MEP models develop empirical expression for the outcome to forecast future databases' features to promote the usage of sustainable MK concrete. Moreover, detrimental effects caused by intensive and costly labor work can be overcome by utilizing these environmental-friendly techniques.

Phytoremediation as an Effective Remedy for Removing Trace Elements from Ecosystems.

The pollution of soil by trace elements is a global problem. Conventional methods of soil remediation are often inapplicable, so it is necessary to search intensively for innovative and environment-friendly techniques for cleaning up ecosystems, such as phytoremediation. Basic research methods, their strengths and weaknesses, and the effects of microorganisms on metallophytes and plant endophytes resistant to trace elements (TEs) were summarised and described in this manuscript. Prospectively, bio-combined phytoremediation with microorganisms appears to be an ideal, economically viable and environmentally sound solution. The novelty of the work is the description of the potential of "green roofs" to contribute to the capture and accumulation of many metal-bearing and suspended dust and other toxic compounds resulting from anthropopressure. Attention was drawn to the great potential of using phytoremediation on less contaminated soils located along traffic routes and urban parks and green spaces. It also focused on the supportive treatments for phytoremediation using genetic engineering, sorbents, phytohormones, microbiota, microalgae or nanoparticles and highlighted the important role of energy crops in phytoremediation. Perceptions of phytoremediation on different continents are also presented, and new international perspectives are presented. Further development of phytoremediation requires much more funding and increased interdisciplinary research in this direction.

Different strategies and bio-removal mechanisms of petroleum hydrocarbons from contaminated sites

PurposePetroleum hydrocarbons are naturally occurring flammable fossil fuels used as conventional energy sources. It has carcinogenic, mutagenic properties and is considered a hazardous pollutant. Soil contaminated with petroleum hydrocarbons adversely affects the properties of soil. This paper aim to remove pollutants from the environment is an urgent need of the hour to maintain the proper functioning of soil ecosystems.Design/methodology/approachThe ability of micro-organisms to degrade petroleum hydrocarbons makes it possible to use these microorganisms to clean the environment from petroleum pollution. For preparing this review, research papers and review articles related to petroleum hydrocarbons degradation by micro-organisms were collected from journals and various search engines.FindingsVarious physical and chemical methods are used for remediation of petroleum hydrocarbons contaminants. However, these methods have several disadvantages. This paper will discuss a novel understanding of petroleum hydrocarbons degradation and how micro-organisms help in petroleum-contaminated soil restoration. Bioremediation is recognized as the most environment-friendly technique for remediation. The research studies demonstrated that bacterial consortium have high biodegradation rate of petroleum hydrocarbons ranging from 83% to 89%.Social implicationsProper management of petroleum hydrocarbons pollutants from the environment is necessary because of their toxicity effects on human and environmental health.Originality/valueThis paper discussed novel mechanisms adopted by bacteria for biodegradation of petroleum hydrocarbons, aerobic and anaerobic biodegradation pathways, genes and enzymes involved in petroleum hydrocarbons biodegradation.

Enrichment, sources, and distributions of toxic elements in the farming land's topsoil near a heavily industrialized area of central Bangladesh, and associated risks assessment

Toxic element accumulation in the surrounding soils of the advanced industry- and agriculture-oriented areas may lead to severe environmental degradation and harmful impact on inhabitants. This work examined the concentration of some concerned toxic elements (Cr, Pb, Cd, Cu, As, and Ni) in the representative topsoil from 10 industrially contaminated sites in central Bangladesh (Narayanganj district) using an Inductively Coupled Plasma Mass Spectrometer concerning the probable ecological and human health risks. The mean concentrations (mg/kg) of the elements were found in the order of Ni (58.1 ± 11.8) > Pb (34.1 ± 14.3) > Cr (32.1 ± 6.77) > Cu (14.5 ± 3.30) > Cd (2.74 ± 1.08) > As (1.49 ± 0.43). The findings pointed out that diversified manmade events enhanced the intensities of elemental contamination through the studied sites. Source analysis showed that Cr, Pb, As, and Cd may originate from industrial wastewater and agricultural activities, whereas Cu and Ni came from natural sources. The geo-accumulation index level for Cd (1.70–3.39) was determined as grade 3 (moderately to strongly polluted), the enrichment factor score for Cd (13.9) fell in the very severe enhanced category (cluster 5), and the highest contamination factor value was found for Cd (15.7). The contamination degree values for all the tested elements signify a moderate to severe contamination grade; conversely, pollution load index levels depicted the nonexistence of elemental pollution. The assessment revealed serious Cd pollution in agricultural soils and moderate to significant potential ecological risk for the rest of the examined toxic elements. Furthermore, hazard index values exceeded the safe exposure levels, indicating that there was potential non-carcinogenic risk in the soils for children and adults. Ingestion exposure had much higher carcinogenic risk values than inhalation and cutaneous exposure, and children are exposed to considerable carcinogenic hazards. Therefore, it is suggested that the harmful practices that expose this farming soil to contaminants should be stopped immediately and effective environment-friendly techniques of waste management and effluent treatment should be employed in the study area.

Xylitol Production by Candida tropicalis from Areca Nut Husk Enzymatic Hydrolysate and Crystallization.

Lignocellulosic biomasses are extensively used by researchers to produce a variety of renewable bioproducts. This research described an environment-friendly technique of xylitol production by an adapted strain of Candida tropicalis from areca nut hemicellulosic hydrolysate, produced through enzymatic hydrolysis. To enhance the activity of xylanase enzymes, lime and acid pretreatment was conducted to make biomass more amenable for saccharification. To improve the efficiency of enzymatic hydrolysis, saccharification parameters like xylanase enzyme loading were varied. Results exposed that the highest yield (g/g) of reducing sugar, about 90%, 83%, and 15%, were achieved for acid-treated husk (ATH), lime-treated husk (LTH), and raw husk (RH) at an enzyme loading of 15.0IU/g. Hydrolysis was conducted at a substrate loading of 2% (w/V) at 30°C, 100rpm agitation, for 12h hydrolysis time at pH 4.5 to 5.0. Subsequently, fermentation of xylose-rich hemicellulose hydrolysate was conducted with pentose utilizing the yeast Candida tropicalis to produce xylitol. The optimum concentration of xylitol was obtained at about 2.47g/L, 3.83g/L, and 5.88g/L, with yields of approximately 71.02%, 76.78%, and 79.68% for raw fermentative hydrolysate (RFH), acid-treated fermentative hydrolysate (ATFH), and lime-treated fermentative gydrolysate (LTFH), respectively. Purification and crystallization were also conducted to separate xylitol crystals, followed by characterization like X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. Results obtained from crystallization were auspicious, and about 85% pure xylitol crystal was obtained.

Trends in digital detection for the quality and safety of herbs using infrared and Raman spectroscopy.

Herbs have been used as natural remedies for disease treatment, prevention, and health care. Some herbs with functional properties are also used as food or food additives for culinary purposes. The quality and safety inspection of herbs are influenced by various factors, which need to be assessed in each operation across the whole process of herb production. Traditional analysis methods are time-consuming and laborious, without quick response, which limits industry development and digital detection. Considering the efficiency and accuracy, faster, cheaper, and more environment-friendly techniques are highly needed to complement or replace the conventional chemical analysis methods. Infrared (IR) and Raman spectroscopy techniques have been applied to the quality control and safety inspection of herbs during the last several decades. In this paper, we generalize the current application using IR and Raman spectroscopy techniques across the whole process, from raw materials to patent herbal products. The challenges and remarks were proposed in the end, which serve as references for improving herb detection based on IR and Raman spectroscopy techniques. Meanwhile, make a path to driving intelligence and automation of herb products factories.

Photocatalytic, antioxidant and antibacterial potential of bio-synthesized ZnO nanoparticles derived from espresso spent coffee grounds: optimization by central composite design

This article presents a rapid, costless, and environment-friendly technique for the biosynthesis of ultra-small ZnO nanoparticles (NPs), which were synthesized using espresso spent coffee grounds (SCG). The synthesized ZnO NPs were determined by Field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR). The photocatalytic activity of the ZnO NPs was evaluated for photodegradation of tartrazine (Tz) dye under UV light. The response surface method (RSM) in a central composite rotatable design (CCRD) was used to design the experiments. The parameters affecting the efficiency of the degradation were evaluated and optimized. The ZnO NPs were assessed for antimicrobial and antioxidant activities. The results showed that XRD, FESEM, and FT-IR confirmed the formation of ZnO NPs. At optimized values, high removal efficiencies (92.5%) were found. Significant antioxidant activity of the NPs was demonstrated using a DPPH (2, 2-diphenyl-1-picrylhydrazyl) free radical assay with the IC50 value of 0.9586 mg/mL.

Dealing With Security Issues In IoT

IoT (Internet of Things) is related to design of a lot of iinter-related “contrived" gadgets having finite capacities with regard to memory and processing power and design is like an Internet. These are frequently battery-driven, raises requirement for adopting environment-friendly techniques. Between the noteworthy ultimatum that establishing interrelated smart objects accompanies are uniformity and coordination. Many smart objects are presumed to develop and addresses of IPv4 are normally utilized. IPv6 is recognized as a possibility for smartobject transmission. Internet of Things (IoT) is a global network of physical and virtual ‘things’ connected to the internet. All objects have unique IDs that are utilized for identification. IoT is the emerging technology which can change the way we communicate with devices. Hereafter almost every electronic device will be a smart device that will be able to compute and communicate with handheld and other infrastructure gadgets. The Internet of Things utilization builds a lot of security problems, which arises from • Smart objects essence: utilization of cryptographic algorithms which are delicate, with regard to requirements of processing and memory. • Quality protocols utilization and the requirement to reduce the data quantity swapped among nodes. An IoT usage which accumulates or handles consumer distinctive data like bank particulars require a foremost rank of security, while a sensor linked to a station area will have a low rank. It need not be costly to carry out fundamental security steps; but it is significant to determine a security strategy and incorporate recuperation measures in the security problems incidents. The main aim of this topic is to describe mechanisms which can help to deal with IoT security issues.

Synthesis of ZnO nanoparticles from zinc acetate dihydrate – An environmental friendly technique

The present work describes a plant-mediated method for the synthesis of Zinc Oxide (ZnO) nanoparticles. The native medicinal herb Pistia Stratiotes plant extract and the Zinc Acetate derivative were used to successfully produce the ZnO nanoparticles (NPs). Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy were used to analyze the ZnO nanoparticles that were produced. The morphology and shape of the NPs were examined using SEM. The functional group present in the leaf extract was determined by FTIR spectroscopy and the CH stretching and NH bonding of ZnO were also observed. The antibacterial activity of ZnO NPs was examined against gram-negative and gram-positive bacterial strains such as Klebsiella Pneumoniae and Bacillus Subtilis in different solvent extracts. The synthesized ZnO NPs exhibited significant inhibitory activity against the pathogenic bacterial strains.

In-situ growth of Cs2AgBiBr6 perovskite nanocrystals on Ti3C2Tx MXene nanosheets for enhanced photocatalytic activity

Photocatalytic degradation of organic dyes is an efficient, safe and environmentally-friendly technique for improving environmental purification. Exploring high-quality and low-cost photocatalysts for photocatalytic degradation with enhanced light harvesting capability and efficient charge separation and transport remains a challenge. Herein, we utilize the two-dimensional (2D) MXene, Ti3C2Tx nanosheets as a high efficiency co-catalyst to construct the Cs2AgBiBr6/Ti3C2Tx Schottky heterostructure by in-situ growth of Cs2AgBiBr6 perovskite NCs on Ti3C2Tx nanosheets via thermal injection method. The optimized Cs2AgBiBr6/Ti3C2Tx nanocomposites show a substantially enhanced organic dye degradation rate, which is ∼4.7 times higher than that of the pristine Cs2AgBiBr6 NCs. Such outstanding photocatalytic activity of Cs2AgBiBr6/Ti3C2Tx nanocomposites stems from the strong interaction between Cs2AgBiBr6 NCs and highly conductive 2D Ti3C2Tx nanosheets, a large interface contact area, and the favorable Fermi level alignment, which significantly promote the charge transfer and separation efficiency while suppressing the electron-hole recombination. More importantly, the Cs2AgBiBr6/MXenes–based photocatalysts exhibit good repeatability and long-term stability. It is demonstrated that this work will guide the construction of high-efficiency and stable photocatalytic materials for environmental purification.

Comparative transcriptome-wide identification and differential expression of genes and lncRNAs in rice near-isogenic line (KW-Bph36-NIL) in response to BPH feeding.

Brown planthopper (BPH) is the most devastating pest of rice in Asia, causing substantial yield losses and has become a challenging task to be controlled under field conditions. Although extensive measures have been taken over the past decades, which resulted in the evolution of new resistant BPH strains. Therefore, besides other possible approaches, equipping host plants with resistant genes is the most effective and environment-friendly technique for BPH control. Here, we systematically analyzed transcriptome changes in the susceptible rice variety Kangwenqingzhan (KW) and the resistant near-isogenic line (NIL) KW-Bph36-NIL, through RNA-seq, depicting the differential expression profiles of mRNAs and long non-coding RNAs (lncRNAs) in rice before and after BPH feeding. We observed a proportion of genes (1.48%) and (2.74%) were altered in KW and NIL, respectively, indicating different responses of rice strains against BPH feeding. Nevertheless, we characterized 384 differentially expressed long non-coding RNAs (DELs) that can be impacted by the two strains by alternatively changing the expression patterns of the respective coding genes, suggesting their certain involvement in response to BPH feeding. In BPH invasion, KW and NIL responded differently by modifying the synthesis, storage, and transformation of intracellular substances, adjusting the nutrient accumulation and utilization inside and outside the cells. In addition, NIL expressed stronger resistance by acutely up-regulating genes and other transcription factors related to stress resistance and plant immunity. Altogether, our study elaborates valuable insights into the genome-wide DEGs and DELs expression profiles of rice under BPH invasion by high throughput sequencing and further suggests that NILs can be utilized in BPH resistance breeding programs in developing high-resistance rice lines.

An experimental and numerical study of pool boiling heat transfer in Cu foam-enhanced cells with interlaced microchannels

Pool boiling heat transfer has an extensive range of applications in energy transfer processes and, as an environmentally-friendly technique, is in line with Chinese “dual carbon” climate goals. In this paper, we looked at how the addition of Cu-interlaced microchannels and Cu foam-interlaced microchannels affected the heat transfer surface of a pool boiling in deionized water. The heat transfer surface was laser-etched with interlaced microchannels of the same width and depth, but different spacing, and the results showed that the critical heat flux (CHF) and heat transfer coefficient (HTC) were strengthened. A Cu foam-interlaced microchannel composite structure with a spacing of 350 µm had the best strengthening effect on the heat transfer surface and, compared with polished copper, △T was reduced by 5.6 °C, the CHF was increased by a maximum factor of 4.41, and the HTC was increased by a factor of 6.98. The results of simulations performed using ANSYS Workbench D matched those of the experimental study.

Analysis of the environmental impacts of the agricultural, industrial, and financial sectors in Malaysia

The mounting level of environmental degradation in Malaysia constitutes a grave issue to analysts and policymakers because it has adverse impact on climate change and human lives. This study is motivated by the dearth of a comprehensive research on the environmental impact of sectoral growth. It focuses on sectoral growth because of the need to strike a balance between the economic and environmental impacts of the agricultural, industrial, and financial sectors in Malaysia. Therefore, this study analyses the environmental impacts of the agricultural, industrial, and financial sectors in Malaysia during 1980–2018. It uses ecological footprint and carbon emissions as indicators of environmental degradation to properly capture various aspects of environmental degradation. It employs the Environmental Kuznets Curve (EKC) model and Autoregressive Distributed Lag (ARDL) procedure. This study contributes to the extant literature by showing that the agricultural, industrial, and market-based financial sectors aggravate carbon emissions while the bank-based financial sector mitigates carbon emissions in Malaysia. However, the impacts of the agricultural, industrial, and financial sectors on ecological footprint are tenuous. Though the EKC hypothesis is verified, energy consumption worsens ecological footprint and carbon emissions. The findings are robust to structural breaks and satisfactory diagnostic tests. This study implies that the agricultural, industrial, and financial sectors are significant determinants of carbon emissions. Since Malaysia cannot afford to sacrifice sectoral development for environmental sustainability, it is necessary for stakeholders to embrace environmental-friendly techniques that can boost sectoral development without compromising environmental quality.

An environment-friendly technique for direct air capture of carbon dioxide via a designed cellulose and calcium system

As a carbon negative emission technique for the ever-increasing demand of sustainable development and climate control, the direct air capture (DAC) has attracted tremendous research attention in recent years. By means of DAC, herein a facile method has been developed to capture CO2 with a designed system of biomass cellulose-added Ca2+ solution. The resultant calcite CaCO3 is found to be uniformly attached to the cellulose fibrils. Compared to a non-cellulose system, cellulose raises the CO2 capture efficiency by 32%. The CO2 capture capacity reaches as high as 7.3 mmol g−1. In the composite cellulose@CaCO3 (CelCa), the chemical interfacial coupling has been revealed by both experimental findings and density functional theory calculations. Two routes have been suggested for the release of CO2. Firstly, CelCa is shaped into a practical filter, which accomplishes an ion exchange with Pb2+ that comes from the discharge effluents of factories. The cellulose@PbCO3 (CelPb) has been accessible, which would significantly lower the calcination temperature for CO2 release and consume much less energy than CaCO3. Secondly, CelPb is treated with acid to release CO2, while cellulose and calcium ion are re-cycled. In short, the whole processing design is cost effective and environment friendly, which suggests its good prospective application in the field of CO2 emission control.

Green in-situ synthesis of silver coated textiles for wide hygiene and healthcare applications

In this study, antibacterial and biocompatible silver-based (Ag0) coatings on cotton fabric were obtained by using atmospheric pressure plasma mediated in situ silver reduction, an effective, facile, and environment-friendly technique. The formation of the thin (nanometers in thickness) Ag0 coating on the fabric fibers was characterized by scanning electron microscopy (SEM) and backscattered electron (BSE) analysis. In particular, the antibacterial activity demonstrated by the silver-fabrics (Ag0-fabrics) against gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria was about 105 times more potent than silver ion or silver nanoparticle fabricated fabrics. The Ag0-fabrics also demonstrated good killing activity to preformed biofilms. Moreover, because of the greatly reduced silver loading, Ag0-fabrics did not pose significant cytotoxicity to human tissue cells exhibiting good biocompatibility. Given the economic and environment-friendly nature of the Ag0-fabrics technology wide applications can be derived in health, hygiene, and medical fields.

High-efficient Photoelectrochemical Reduction of Cr(VI) to Produce Chromium Formate over Pure Bi2S3 Thin Films

As a typical heavy metal ion pollutant in water and soil, Cr(VI) exhibits significant toxicity and carcinogenicity, which urges the development of an effective and environment-friendly technique for Cr(VI) treatment. Herein, bismuth sulfide (Bi2S3) photoanode is fabricated through a chemical bath deposition followed by sulfurization treatments. The structure and physicochemical characteristics of the thin films were analyzed and optimized. The obtained Bi2S3 thin films exhibit the photocurrent of 5.37 mA·cm−2 at 1.22 V vs RHE. It can achieve 100% reduction efficiency of 70 ppm Cr(VI) solution in 1 h, and the reduction rate is 159.47 × 10−3 μmol·min−1·cm−2. Further, the mechanism of the photoelectrochemical reaction was explored, and the reduced Cr(Ⅲ) was converted into industrial raw material chromium formate, which realized the harmless recycling of Cr(VI)-contaminated wastewater.

Tversky Similarity based Deep Neural Learning Classification for Engineering Alloys

Integrated Computational Materials Engineering (ICME) is an environment friendly technique used for performing cloth discovery and design. Computational methods introduced a new deep studying classification approach to display screen the candidate cloth designs. During the product designing stage, the ingredients are customised to meet particular needs. In ICME processes, there is always a degree of uncertainty in the process, structure, and property components. Uncertainties may be quantified, reduced, and propagated via structure–property links using the Tversky Similarity based Deep Neural Learning Classification (TS-DNLC) Method. In TS-DNLC Method, number of compound data are considered as input and given to the input layer. An input compound data is given to hidden layer 1. In that layer, regression is employed for performing the compound data analysis with structure–property linkages. After that, the regression coefficient value is sent to the hidden layer 2. In that layer, Tversky similarity function is used to identify the similarity between the regression coefficient value of training compound data and threshold value. Tversky similarity value varies from 0 to 1 and the results are transmitted to the output layer. By this way, TS-DNLC Method improves the performance of structure–property linkages. The computational cost of proposed TS-DNLC Method is higher than conventional uncertainty quantification.

Selective solar-driven CO2 reduction mediated by 2D/2D Bi2O2SiO3/MXene nanosheets heterojunction

• An ecofriendly 2D/2D heterojunction of Bi 2 O 2 SiO 3 /Ti 3 C 2 was synthesized by a simple wet chemical process. • 2D/2D Bi 2 O 2 SiO 3 /Ti 3 C 2 heterojunction boosts the photo-reactivity of Bi 2 O 2 SiO 3 for CO 2 reduction. • The 2D/2D heterojunction own a short charge transfer distance resulting in effective charge transfer. • The enhanced photocatalytic mechanism of the system was clarified by DFT study. Photocatalytic CO 2 reduction reaction (CO 2 RR) is an environment-friendly technique for clean fuel generation. Developing low-cost and efficient photocatalyst/cocatalyst systems for boosting CO 2 RR is still a challenge. Herein, a novel Bi 2 O 2 SiO 3 /Ti 3 C 2 2D/2D heterojunction photocatalysts are successfully prepared by in situ growth of Bi 2 O 2 SiO 3 on the surface of ultrathin Ti 3 C 2 nanosheets, a kind of MXenes. The observed Bi 2 O 2 SiO 3 /Ti 3 C 2 (BOSO/TC-2) hybrids exhibit a large interface contact area companied with enhanced CO 2 adsorption capability, illustrating excellent 2D/2D interfacial charge transfer behaviors. The total yield of products obtained on the optimized BOSO/TC-2 photocatalyst is 3.8 times that of pristine Bi 2 O 2 SiO 3 nanosheets and achieve near 90% selectivity for CO over CH 3 OH without sacrificial agents, which was higher than most all inorganic Bi-based photocatalysts. Moreover, the mechanism of enhanced photocatalytic activity and reaction pathway was proposed in terms of the DFT study and in situ FTIR analysis. This work might provide new semiconductor/cocatalyst systems for selective CO 2 photoreduction to solar fuels.

Eco-friendly preparation of Bi2O3, Ag-Bi2O3 and Ag-Bi2O3-rGO nanomaterials and their photocatalytic H2 evolution, dye degradation, nitrite sensing and biological applications

The current studies demonstrate the preparation of Bi2O3, Ag-Bi2O3, Ag-Bi2O3-rGO nanocomposite using a clear and concise, environmentally sustainable, low-cost green combustion method employing citrus limon as fuel. The synthesised materials were characterised through XRD, UV-DRS, FT-IR, TGA, TEM, SEM and Raman studies. The synthesised Ag-Bi2O3-rGO composite exhibited much improved photocatalytic H2 evolution activity (432.7 μmolg-1h−1) which is 5.5 times greater than bare-Bi2O3 (78.6 μmolg-1h−1) and 4.2 times greater than Ag-Bi2O3 (101.2 μmolg-1h−1) NPs. Further, Bi2O3, Ag-Bi2O3 and Ag-Bi2O3-rGO composite degraded the MB dye by 63.96, 74.9 and 100 % respectively in 90 min. Ag-Bi2O3-rGO exhibited superior electrochemical nitrite sensing property (with the LOD of 19.792 μM). Ag-Bi2O3-rGO nanocomposite exhibited potential antiradical property with IC50 of 900 μg/mL Ag-Bi2O3-rGO was found to have potent direct haemolytic, anticoagulant, antiplatelet and antibacterial activities. This study illustrates a simple, environmental friendly green synthetic technique for large-scale synthesis of multifunctional Ag-Bi2O3-rGO nanocomposite.