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• An ultrathin thermally oxidized metal film is used as a hole transporting layer in p-i-n perovskite solar cells. • A PCE of 6.7% for the HTL thickness as low as 1 nm has been obtained and that for 5 nm HTL is 11.44%. • The best performing device shows over 80% of its initial performance even after 1000 h in an ambient environment without any encapsulation. • Transmittance, surface roughness, grain size, crystal structure, and composition were studied and implemented in device optimization. The use of inorganic materials is generally considered a prerequisite for the realization of inexpensive and long-lasting perovskite solar cells (PvSCs). Herein, we have demonstrated a low-cost, inorganic, ultrathin thermally oxidized copper film (Cu_Oxd) as a hole transport layer (HTL) in PvSC in p-i-n geometry with MAPbI 3 as the photoactive layer. A highly reproducible technique of vapor deposition (magnetron sputtering) followed by thermal annealing has been used to deposit the Cu_Oxd layer over an ITO-coated glass substrate. The material properties of the Cu_Oxd film have been thoroughly investigated and their effect on photovoltaic properties and the photoactive absorbing layer has been studied in detail and correlated. Photovoltaic performance of the devices fabricated with different Cu_Oxd thicknesses has been measured and a maximum PCE of 11.44% has been obtained with a 5 nm thickness of Cu_Oxd layer as HTL with a pixel area of 0.25 cm2. The devices showed higher stability with T80 lifetime >1000 h without any encapsulation. With the ease of fabrication and compatibility with large-area devices, Cu_Oxd as HTL can be scaled up and also, help in the progress towards large-scale fabrication and commercialization. [ABSTRACT FROM AUTHOR]

Herein, a polyhydroxy containing metallo porphyrin linked through amide functional group with Anderson polyoxometalate (POM) was used to form TPMnA-COF. Structure and applications have been unlocked thoroughly by means of FT-IR, UV–visible, 1HNMR, PXRD, SEM and cyclic voltammetric (CV) spectral analysis. The TPMnA-COF was tested as catalyst to explore the photocurrent and photodegradation properties. ITO electrode was fabricated to study optical activity, absorption study and photocurrent generation. The adsorption study of TPMnA-COF has been studied using Langmuir and Freundlich model with calculated Langmuir constants q m , K L , R L and R2 values of about 12.42 mg/g, 0.33 M-1, 0.30 and 0.98 respectively. The 1/n, K f and R2 values obtained from Freundlich adsorption isotherm were 0.70, 3.16 M-1 and 0.96 respectively. The band gap value evaluated via absorption edge of UV–visible spectra in DMSO solution was 2.75 eV while the band gap value calculated for ultra-thin film was 1.95 eV. The calculated real, imaginary dielectric constants, Urbach edge, refractive index and the electrical conductivity values for ultra-thin film of TPMnA-COF were 518.8, 2.9 × 10−11-8.1 × 10−11, −3.802 meV, 22.8–22.6 and 8.3 × 104−3.4 × 104 S/m), respectively. Responsivity for film was also tested using purple, blue, green, yellow, orange and red colourlights and the observed responsivity for different lower light intensities were 3.05, 2.9, 1.6, 1.55, 1.5 and 1.4 mA/W respectively. Furthermore, photodegradation activity of TPMnA-COF in Methylene-Blue (MB) and Rhodamine B(Rh–B) dyes under 3 W light. The results showed higher photocatalytic efficiency for Rh–B than that for MB with obtained degradation efficiency of 81 % and 60.4 %, respectively after 660 min. The scavengers such as ammonium oxalate (AO, h+), isopropanol (ISOP, •OH), catalase (CAT, H 2 O 2) and superoxide dismutase (SODM, O 2 −●) were used to find out the effectiveness of each reactive specie to degrade the dyes solution in the mechanism of degradation. It was observed that AO (h+) and ISOP(•OH) were more active species in the photodegradation mechanism than CAT(H 2 O 2) and SODM(O 2 −●). [Display omitted] • In this article we have reported. • A Covalent Organic Framework (COF) named as TPMnA-COF synthesized from a tetrafucntionalized metallo porphyrin attached via amide functionaity with Anderson polyoxometalate (POM). • Characterization has been thoroughly done by means of FT-IR, UV–visible, 1HNMR, PXRD, SEM and cyclic voltammetric (CV) spectral analysis and tested to uncover the photocurrent generation, optical properties, adsorption study and photodegradation properties. • TPMnA-COF was used to fabricate the ITO electrode to calculate real, imaginary dielectric constants, Urbach edge, refractive index and the electrical conductivity under different intensities of light. • Furthermore, photodegradation activity of TP@MnA-COF in Methylene-Blue (MB) and Rhodamine B(Rh–B) dyes and along with some scavenger's ammonium oxalate (AO, h+), isopropanol (ISOP,.•OH), catalase (CAT, H 2 O 2) and superoxide dismutase (SODM, O 2 −●)under 3 W light was also observed after 660min time interval. [ABSTRACT FROM AUTHOR]

Energy loss straggling of energetic Li, C and O ions in varying thicknesses of self-supporting Titanium foils is measured, in the fractional energy loss limits (ΔE/E) ~ 5–50%. For these measurements, transmission technique is utilized and recorded energy spectra are estimated through Gauss fitting function. The measured straggling values are compared with the prediction of most commonly used collisional (Bohr, Lindhard-Scharff, Bethe-Livingston, Titeica) and collisional plus charge-exchange (Yang et al.) straggling formulations. Titeica theory, which is considering collisional straggling only, shows lesser deviations with the measured values. Based on the present measurements, the fitted relations for charge-exchange straggling is developed. • Energy loss straggling, in self supporting foils, through transmission technique is measured. • Titeica theory based predicted values show better agreement with the measured values. • The fitted relation for charge-exchange straggling is developed. • The linear relation between energy loss straggling and energy loss is observed. [ABSTRACT FROM AUTHOR]

Energy loss and associated parameters (energy loss straggling, skewness and kurtosis), in energy loss spectrum of Li, C and O ions, are measured in varying thicknesses of Ni metallic foils. Energy loss and straggling measured values are compared with the corresponding computed values adopting respective theoretical/semi-empirical formulations, with the motive to identify the best formulation. Further, skewness and kurtosis are measured to confirm the shape of recorded energy spectra. The study of these parameters, for different ion beams in variety of target materials, is important for understanding of basic ion-matter interaction processes as well as these parameters are used as inputs in various computer simulation codes (SIMNRA, RUMP, NDF) for the analysis of energy spectra obtained through different ion beam techniques. • Energy loss, straggling, skewness and kurtosis associated with energy spectra of Li, C and O ions are measured. • The measurements are performed through transmission technique. • Benton and Henke formulation is found to be in excellent agreement with the measured energy loss values. • Titeica straggling theory shows better agreement with the measured straggling values. • Measured skewness and kurtosis ascertain that energy spectra are mesokurtic type Gaussian distribution. [ABSTRACT FROM AUTHOR]

Based on the available measured energy loss data, the fitting coefficients involved in effective charge parameterization of Hubert et al. formulation are re-revised and developed the energy loss formulation for heavy ions with Z 1 = 3–36 in the energy region ~0.2–3.0 MeV/n. The computed values based on the presently developed formulation are compared with the measured values and found good agreement in both elemental and polymeric materials. • Fitted expression for effective charge, of heavy with Z 1 = 3–36, is developed. • The considered ion's energy region ~0.2–3.0 MeV/n covers the Bragg's peak region. • Energy loss values in both elemental and polymeric materials are computed. • The computed values show good agreement with the measured values. [ABSTRACT FROM AUTHOR]

Conventional rice-wheat cropping system (RWCS) in western Indo-Gangetic Plains (IGP) is carbon and energy intensive. A field experiment was conducted to evaluate energy budgeting, carbon footprints (CF) and greenhouse gas (GHG) emissions from RWCS under long-term tillage and residue management practices. Experiment consisted six treatment combination of tillage [conventional tillage (CT), reduced tillage (RT) and zero tillage (ZT)] and residue [with residue (+R) and without residue (–R)] namely (i) CT-R (conventional farmers' practice), (ii) CT + R, (iii) RT-R, (iv) RT + R, (v) ZT-R and (vi) ZT + R. Energy consumption ranged from 51.87 GJ ha−1 (ZT-R) to 64.91 GJ ha−1 (CT + R) and irrigation water was major energy intensive input (41–44%) followed by chemical fertilizer (32–40%). Compared to CT-R, energy use efficiency (EUE) increased by 8.7–22.4%, CF lowered by 77.9–34.3%, and GHG emission lowered by 12.8–16.3% in different treatments. Residue addition enhanced the soil carbon accumulation in ZT + R (1213 kg C ha−1 yr−1) and RT + R (987 kg C ha−1 yr−1). Overall, switching from CT–R to ZT + R lowered energy consumption (19%), GHG emission (16%) and CF (78%), making it best-bet option for climate change mitigation and global warming related environmental protection in western IGP and similar agro–ecologies. [Display omitted] • Energy use efficiency (EUE), Greenhouse gases (GHGs) emission and carbon footprints (CF) were analysed. • Irrigation water contribute maximum (41–44%) share of input energy followed chemical fertilizers (32–40%). • Conservation tillage and residue management enhanced energy productivity (15.8–21.0%) and EUE (17.1–22.4%). • The CF lowered by 77.9% in zero tillage with residue to 45.2% in reduced tillage without residue. • Zero tillage with residue addition is most energy efficient system with lower GHG emission and carbon footprint. [ABSTRACT FROM AUTHOR]