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In this article, the impact of the loading of CdS between Pt and 3D graphene was investigated determining enhanced visible light absorption and efficient charge separation at the interfaces that have improved methanol oxidation reaction activities. The structural, morphological, optical and electrochemical properties of photoanodes were investigated. The highest current density reached 264 mA cm−2 at 0.28 V vs. Ag/AgCl under one sun illumination for Pt/10-CdS/3D-Gr@Ni-Foam as compared to 116 mA cm−2 at 0.26 V for Ag/AgCl in the dark at a scan rate of 10 mV s−1. The diffusion coefficient of electron transfer is also enhanced to 3.99 × 10−3 cm2 s−1 under illumination as compared to 2.971 × 10−3 cm2 s−1 under dark conditions for the Pt/10-CdS/3D-Gr@Ni-Foam heterostructure. The decrease in the charge transfer resistance (Rct) from 34.31 Ω to 2.38 Ω indicated that the introduction of CdS enhanced the separation and transportation of photoexcited charges and also improved the kinetics of the electron transfer reaction. The Pt/10-CdS/3D-Gr@Ni-Foam exhibited a significantly enhanced net donor density (ND) of 2.5 × 1020, surpassing the donor density of 1.5 × 1020 of the Pt/3D-Gr@Ni-Foam. Both Pt and 3D-graphene are being utilized as a well, for efficient charge separation and transportation at either side of the CdS sandwich, resulting in effective transfer of charges at the corresponding Pt/CdS/3D-Gr@Ni-Foam heterostructure interfaces and increased electron density on Pt showed its unprecedented potential to be utilized for electrocatalytic and photo-electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Induced heavy metals (HMs) phytoextraction from heavily contaminated soils is challenging, as high HM bioavailability causes phytotoxicity and leaching. This study introduces a novel approach for HM immobilization with biochar (BC) and lignin (LN), and later their controlled mobilization with citric acid (CA) in soil. Conocarpus erectus was grown for 120 days in shooting-range soil (SS) polluted with Pb, Cr, Cd, Ni, and Cu. HM concentrations in parts of the plants, their percentage removal, and leaching from SS were measured. Moreover, plant biochemical parameters such as the contents of chlorophyll a (Chl-a), chlorophyll b (Chl-b), protein, ascorbic acid (AsA), amino acids, and total phenolics, along with biophysical parameters such as relative water content (RWC) and water uptake capacity (WUC), were also inspected. Adding BC, LN, and BC+LN to SS improved biomass, as well as the biophysical and biochemical parameters of plants, while efficiently reducing HM concentrations in plant parts, DTPA extract, and leachates compared to the control (CK). However, the greatest amplifications in plant height (82%), dry weight of root (RDW) (109%), and dry weight of shoot (SDW) (87%), plant health, and soil enzymes were noted with the BC+LN+CA treatment, compared with the CK. Moreover, this treatment resulted in Pb, Cr, Cd, Ni, and Cu removal by 68, 30, 69, 59, and 76% from the SS compared to the CK. Surprisingly, each HM concentration in the leachates with BC+LN+CA was below the critical limits for safer water reuse and agricultural purposes. Initial HM immobilization in HM-polluted soils, followed by their secured mobilization during enhanced phytoextraction, can enhance HM removal and reduce their leaching without compromising plant and soil health. [ABSTRACT FROM AUTHOR]

The synergistic combination of 1D TiO2 nanorods and BiVO4 results in compatible electronic band structure alignment at their interfaces to ensure enhanced photoactivated charge separation and transportation under visible light irradiation. Herein, the plasmonic effect of platinum on 1D BiVO4/TiO2 nanorods was explored to establish charge transfer at the heterojunctions and improve the activities of methanol oxidation. Structural, compositional, morphological and electrochemical performance was explored. Noticeably, 10-Pt/BiVO4/TiO2 showed an excellent current density of 64.6 mA cm−2 under 100 mW cm−2 illumination as compared to 12.5 mA cm−2 under dark conditions. Moreover, the highest lifetime of 227.3 ms under light was observed as compared to 63.6 ms under dark conditions. Moreover, electrochemical impedance spectroscopy (EIS) studies of 10-Pt/BiVO4/TiO2 showed the least charge transfer resistance (Rct) of 161 Ω under one sun light in comparison to 385 Ω under dark conditions. Moreover, the methanol oxidation reaction (MOR) efficiency for 5, 10 and 15 cycles of Pt over BiVO4/TiO2 was found to be 335%, 417% and 78%, respectively. The surface plasmon resonance (SPR) property of Pt was enhanced with the substrate of the 1D BiVO4/TiO2 heterojunction, and this strategy showed its unprecedented potential to be utilized for electrocatalytic and photo-electrocatalytic applications. [ABSTRACT FROM AUTHOR]