Textile wastewater heavy metal pollution has become a severe environmental problem worldwide. Metal ion inclusion in a dye molecule exhibits a bathochromic shift producing deeper but duller shades, which provides excellent colouration. The ejection of a massive volume of wastewater containing heavy metal ions such as Cr (VI), Pb (II), Cd (II) and Zn (II) and metal‐containing dyes are an unavoidable consequence because the textile industry consumes large quantities of water and all these chemicals cannot be combined entirely with fibres during the dyeing process. These high concentrations of chemicals in effluents interfere with the natural water resources, cause severe toxicological implications on the environment with a dramatic impact on human health. This article reviewed the various metal‐containing dye types and their heavy metal ions pollution from entryway to the wastewater, which then briefly explored the effects on human health and the environment. Graphene‐based absorbers, specially graphene oxide (GO) benefits from an ordered structured, high specific surface area, and flexible surface functionalization options, which are indispensable to realize a high performance of heavy metal ion removal. These exceptional adsorption properties of graphene‐based materials support a position of ubiquity in our everyday lives. The collective representation of the textile wastewater‘s effective remediation methods is discussed and focused on the GO‐based adsorption methods. Understanding the critical impact regarding the GO‐based materials established adsorption portfolio for heavy metal ions removal are also discussed. Various heavy‐metal ions and their pollutant effect, ways to remove such heavy metal ions and role of graphene‐based adsorbent including their demand, perspective, limitation, and relative scopes are discussed elaborately in the review.

The accumulation of soiling on photovoltaic (PV) modules affects PV systems worldwide. Soiling consists of mineral dust, soot particles, aerosols, pollen, fungi and/or other contaminants that deposit on the surface of PV modules. Soiling absorbs, scatters, and reflects a fraction of the incoming sunlight, reducing the intensity that reaches the active part of the solar cell. Here, we report on the comparison of naturally accumulated soiling on coupons of PV glass soiled at seven locations worldwide. The spectral hemispherical transmittance was measured. It was found that natural soiling disproportionately impacts the blue and ultraviolet (UV) portions of the spectrum compared to the visible and infrared (iR). Also, the general shape of the transmittance spectra was similar at all the studied sites and could adequately be described by a modified form of the Ångström turbidity equation. In addition, the distribution of particles sizes was found to follow the IEST-STD-CC 1246E cleanliness standard. The fractional coverage of the glass surface by particles could be determined directly or indirectly and, as expected, has a linear correlation with the transmittance. It thus becomes feasible to estimate the optical consequences of the soiling of pV modules from the particle size distribution and the cleanliness value. Soiling has a negative impact on the economic revenues of PV installations, not only because it reduces the amount of energy converted by the PV modules, but also because it introduces additional operating and maintenance costs and, at the same time, increases the uncertainty on the estimation of PV performance, leading to both higher financial risks and interest rates charged to plant developers. Power reductions greater than 50% have been reported in the literature because of soiling 1,2 ; it has been estimated that an average loss of 4% on the global annual energy yield of PV could cause losses in revenue on the order of 2 × 10 9 US$ annually 3. A careful monitoring of soiling is required to mitigate its effect 4. Soiling losses are generally quantified by using soiling stations. These systems are made of at least two PV devices, one of which is regularly cleaned while the other is left to soil naturally. By comparing the ratio of the electrical outputs of the two devices, it is possible to estimate the impact of soiling on the PV performance 5,6. The International Electrotechnical Commission's (IEC) metric to monitor and quantify the impact of soiling on PV modules is the soiling ratio, r s , which expresses the ratio of the electrical output of a soiled PV device to the output of the same device under clean conditions 7. Like the transmittance, a higher soiling ratio translates to less soiling deposited on the modules. A value of 1 indicates clean conditions, with no soiling. For a more detailed definition of r s , please refer to the Methodology section. The fractional loss of solar-generated power due to soiling is 1 − r s .

Here, we report the synthesis of phase pure perforated porous BaSnO 3 (BSO) nanorods and their application as an alternative photoanode in dye sensitized solar cells (DSSCs). BaSnO 3, synthesized using different amounts of dextran, has been characterized through various physicochemical techniques to understand the effect of dextran in controlling its morphology. The porous morphology of the rod facilitated enhanced N719 dye loading capability within a very short duration of 20 min. The dye adsorption behavior of the nanorod has been monitored through UV−vis absorption spectroscopy and contact angle measurements. Further, as an alternative photoanode, a DSSC of active area 0.2826 cm 2 fabricated with the porous BaSnO 3 exhibited a maximum efficiency of 4.31% with a significantly high V OC of 0.82 V whereas, after TiCl 4 treatment, the same cell exhibited an enhanced efficiency of 6.86% under 1 sun AM 1.5. On the basis of our results, we are able to establish porosity as an important factor in reducing the time required for effective dye adsorption which will be highly beneficial for technology development.

The rapid efficiency enhancement of perovskite solar cells (PSCs) make it a promising photovoltaic (PV) research, which has now drawn attention from industries and government organizations to invest for further development of PSC technology. PSC technology continuously develops into new and improved results. However, stability, toxicity, cost, material production and fabrication become the significant factors, which limits the expansion of PSCs. PSCs integration into a building in the form of building-integrated photovoltaic (BIPV) is one of the most holistic approaches to exploit it as a next-generation PV technology. Integration of high efficiency and semi-transparent PSC in BIPV is still not a well-established area. The purpose of this review is to get an overview of the relative scope of PSCs integration in the BIPV sector. This review demonstrates the benevolence of PSCs by stimulating energy conversion and its perspective and gradual evolution in terms of photovoltaic applications to address the challenge of increasing energy demand and their environmental impacts for BIPV adaptation. Understanding the critical impact regarding the materials and devices established portfolio for PSC integration BIPV are also discussed. In addition to highlighting the apparent advantages of using PSCs in terms of their demand, perspective and the limitations, challenges, new strategies of modification and relative scopes are also addressed in this review.

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perovskite solar cells (pScs) composed of organic polymer-based hole-transporting materials (HtMs) are considered to be an important strategy in improving the device performance, to compete with conventional solar cells. Yet the use of such expensive and unstable HTMs, together with hygroscopic perovskite structure remains a concern -an arguable aspect for the prospect of onsite photovoltaic (PV) application. Herein, we have demonstrated the sustainable fabrication of efficient and air-stable PSCs composed of an invasive plant (Eichhornia crassipes) extracted porous graphitic carbon (ec-Gc) which plays a dual role as HTM/counter electrode. The changes in annealing temperature (~450 °C, ~850 °C and ~1000 °C) while extracting the EC-GC, made a significant impact on the degree of graphitization -a remarkable criterion in determining the device performance. Hence, the fabricated champion device-1 c : Glass/fto/c-tio 2 /mp-tio 2 /cH 3 nH 3 pbi 3−x cl x /EC-GC10@CH 3 nH 3 pbi 3−x cl x /EC-GC10) exhibited a PCE of 8.52%. Surprisingly, the introduced EC-GC10 encapsulated perovskite interfacial layer at the perovskite/HtM interface helps in overcoming the moisture degradation of the hygroscopic perovskite layer in which the same champion device-1 c evinced better air stability retaining its efficiency ~94.40% for 1000 hours. We believe that this present work on invasive plant extracted carbon playing a dual role, together as an interfacial layer may pave the way towards a reliable perovskite photovoltaic device at low-cost.Lower cost, shorter payback time and an unprecedented rise in power conversion efficiency (PCE) escalating from 3.8% in 2009 to 24.2% (2019) have turned the attention of researchers and industrial community towards perovskite solar cells (PSCs) within a decade 1-5 . Outstanding photovoltaic properties such as high charge carrier mobility, long electron-hole diffusion length, high absorption coefficient with tuneable bandgap property, low-exciton binding energy, and easy solution preparation techniques make it to compete with traditional commercial silicon solar cells 6,7 . In general, a typical PSC is composed of an electron transport layer (ETL), an active absorbing layer, a HTL, and a counter electrode. Nevertheless, the use of expensive and unstable conducting polymers based hole transporting materials (HTMs) such as (2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenylamine)-9

Graphene (GR) and its derivatives are promising materials on the horizon of nanotechnology and material science and have attracted a tremendous amount of research interest in recent years. The unique atom-thick 2D structure with sp(2) hybridization and large specific surface area, high thermal conductivity, superior electron mobility, and chemical stability have made GR and its derivatives extremely attractive components for composite materials for solar energy conversion, energy storage, environmental purification, and biosensor applications. This review gives a brief introduction of GR's unique structure, band structure engineering, physical and chemical properties, and recent energy-related progress of GR-based materials in the fields of energy conversion (e.g., photocatalysis, photoelectrochemical water splitting, CO2 reduction, dye-sensitized and organic solar cells, and photosensitizers in photovoltaic devices) and energy storage (batteries, fuel cells, and supercapacitors). The vast coverage of advancements in environmental applications of GR-based materials for photocatalytic degradation of organic pollutants, gas sensing, and removal of heavy-metal ions is presented. Additionally, the use of graphene composites in the biosensing field is discussed. We conclude the review with remarks on the challenges, prospects, and further development of GR-based materials in the exciting fields of energy, environment, and bioscience.

Temperature-dependent studies on carbon-based perovskite solar cells (c-PSCs) manifest a less explored area of research compared with the numerous studies on improving the power conversion efficiency (PCE) and stability of...