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Interfacial ionic defects in perovskite solar cells (PSCs) significantly influence the efficiency and long‐term stability. In this study, primarily simulation‐assisted analyses are conducted to explore the capacitive effect of these defects on the performance of PSCs through impedance analysis. Simulated data indicate a decrease in capacitance with increasing frequency, leading to a higher built‐in potential (ΔVbi = 150 mV). Moreover, an increase in capacitance with increasing light intensity is observed. Additionally, reducing the ionic defect concentration at the interfaces (from 1019 to 1016 cm−3) results in more significant band bending and a higher Vbi. Potential solutions to mitigate interfacial ionic defects, including doping at transport layer interfaces are proposed. Doping at both interfaces introduces an energy spike (valence band offset) of 0.21 eV and a cliff (conduction band offset) of 0.16 eV, respectively, for holes and electrons, leading to an improvement in the open circuit voltage (VOC). Finally, experimental results demonstrate a notable enhancement in VOC of 0.04 V with the introduction of Li+ doping at the electron transport layer/perovskite interface. These findings provide essential perceptions for effectively mitigating the effect of interfacial ionic defects on the performance of PSCs and enhance their overall performance. [ABSTRACT FROM AUTHOR]

In this paper, some properties of finitely generated two-periodic modules over commutative Noetherian local rings have been studied. We show that under certain assumptions on a pair of modules (M,N) with M being two-periodic, the natural map M ⊗RN →HomR(M∗,N) is an isomorphism. As a consequence, we prove that Auslander’s depth formula holds for such a Tor-independent pair. Tor-independence plays a crucial role for the depth formula to hold. Under certain assumptions on the modules, we show that a pair of modules, over a one-dimensional local ring, is Tor-independent if and only if their tensor product is torsion-free. Celikbas et al. recently showed the Huneke–Wiegand conjecture holds for two-periodic modules over one-dimensional domains. We generalize their result to the case of two-periodic modules with rank over one-dimensional local rings. [ABSTRACT FROM AUTHOR]

Designing a photocatalyst material with reduced recombination of photogenerated charges is one of the most important aspects of hydrogen generation through solar water splitting. Here, we report hydrogen generation using the TiO2/ultrathin g-C3N4 (U-g-CN) heterostructure fabricated using a unique in situ thermal exfoliation process. Multilayer g-CN is converted into U-g-CN having a high surface (∼190 m2/g) area by calcination at ∼550 °C through oxygen-induced exfoliation, which also forms a robust heterostructure with TiO2. In addition, the presence of g-CN also inhibits further growth of TiO2 nanoparticles, thereby retaining a high specific surface area. The presence of U-g-CN causes a redshift (∼0.13 eV) in the absorption edge of heterostructure compared to that of bare TiO2, which extends the light absorption capability. Addition of 40 wt. % of multilayer g-CN to TiO2 shows an enhanced H2 evolution rate, which is ∼15 times and ∼4 times higher compared to that of bare TiO2 and U-g-CN, respectively. Photoluminescence (PL) and time-resolved PL (TRPL) studies indicate a reduced recombination rate of photogenerated charge carriers with an increase in the average lifetime from 10.53 (TiO2) to 13.32 ns (TiO2/U-g-CN40). The interfacial charge transport characteristics studied through impedance spectroscopy reveal a reduced charge transfer resistance at the semiconductor–electrolyte interface, which facilitates faster charge separation due to the heterostructure formation. The band edge positions are estimated through flatband potential from the Mott–Schottky measurements and optical absorption data, indicating a type-II heterojunction. More light absorption and enhanced separation of photogenerated charges at the heterojunction interface lead to better photocatalytic H2 generation. [ABSTRACT FROM AUTHOR]

The pursuit of efficient and sustainable energy conversion has driven significant research on the development of advanced electrode materials for photoelectrochemical (PEC) water splitting. In this study, we present a novel composite material composed of Z-type multifaceted CuSe and FeSe 2 binary metal selenide nanoparticles (NPs) decorated on a graphene oxide (GO) matrix as an active electrode material for high-performance PEC water splitting applications. The catalytic activity of copper-based catalysts is enhanced by the inclusion of iron (Fe) and selenium (Se), as these elements facilitate the creation of more robust covalent connections between the metal and anion. Further, the presence of an amalgamation of GO, which possesses a substantial surface area and excellent electrical conductivity, enhances oxygen evolution reaction (OER) efficiency. The electrode (i.e., CuSe–FeSe 2 @GO) demonstrated an exceptionally low overpotential of 16.3 mV at a current density of 10 mmA cm−2, a modest Tafel slope of 58.3 mV dec−1, and a current density of 26.04 mA cm−2 in an alkaline aqueous solution under 1 Sun. The detection of superoxide radicals (O2−•) suggests the potential formation of Z-type heterojunctions between CuSe and FeSe 2 NPs. Thus, this research offers a novel approach for the fabrication of resource-rich, economical, and highly active Cu-based catalysts for the OER. [Display omitted] • CuSe and FeSe 2 on GO matrix create novel material for efficient EC & PEC water splitting. • The synergy of CuSe, FeSe 2 , and GO enhances catalysis, forming covalent connections, improving OER efficiency. • CuSe–FeSe 2 @GO electrode exhibits high performance in alkaline solutions under 1 Sun. • The composite provides Cu-based catalysts for sustainable OER, achieving a current density of 26.04 mA cm−2. • The CuSe–FeSe 2 @GO composite shows a remarkable 42.14% improvement in OER efficiency over FeSe 2 @GO. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the response of microbes and bioregulators on yield growth and productivity of chickpea (Cicer arietinum L.) under rainfed condition during 2010-11 and 2011-2012 on sandy loam soils with factorial randomized block design consisting of four levels of biofertilizers inoculation viz., no inoculation, phosphate solubilizing bacteria (PSB), vesicular arbuscular mycorrhizae (VAM) and PSB+VAM with two bio-regulators viz., homo-brassinolide @ 1 ppm and gibberelic acid @ 1000 ppm at pre-flowering and pod-filling stage. Result showed that the yield attributes like number of grains plant-1 and test weight were highest in treatment receiving homo-brassinolide and dual inoculation of PSB+VAM. Grain yield was highest (2139 and 2211 kg ha-1) in treatment receiving PSB+VAM application over no inoculation (957 and 1072 kg ha-1). The grain yield was highest (1705 and 1797 kg ha-1) in treatment receiving homo-brassnolide and lowest grain yield (1481 and 1569 kg ha-1) at gibberelic acid during 2010-11 and 2011-12, respectively. [ABSTRACT FROM AUTHOR]

Irradiation of materials by high energy (∼MeV) ions causes intense electronic excitations through inelastic transfer of energy that significantly modifies physicochemical properties. We report the effect of 100 MeV Ag ion irradiation and resultant localized (∼few nm) thermal spike on vertically oriented TiO 2 nanorods (∼100 nm width) towards tailoring their structural and electronic properties. Rapid quenching of the thermal spike induced molten state within ∼0.5 picosecond results in a distortion in the crystalline structure that increases with increasing fluences (ions per cm 2 ). Microstructural investigations reveal ion track formation along with a corrugated surface of the nanorods. The thermal spike simulation validates the experimental observation of the ion track dimension (∼10 nm diameter) and melting of the nanorods. The optical absorption study shows direct bandgap values of 3.11 eV (pristine) and 3.23 eV (5 × 10 12 ions per cm 2 ) and an indirect bandgap value of 3.10 eV for the highest fluence (5 × 10 13 ions per cm 2 ). First principles electronic structure calculations corroborate the direct-to-indirect transition that is attributed to the structural distortion at the highest fluence. This work presents a unique technique to selectively tune the properties of nanorods for versatile applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)