Department Of Physics

Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/57

Browse

Subject: search.filters.subject.Conversion efficiency

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Janus ?-Te2X (X = S, Se) monolayers for efficient excitonic solar cells and photocatalytic water splitting
    (Royal Society of Chemistry, 2023-01-04T00:00:00) Singh, Jaspreet; Kumar, Ashok
    Highly efficient, environmentally friendly and renewable sources of energy are of great need today to combat increasing energy demands and environmental pollution. In this work, we have investigated the novel 2D allotropes, i.e., ?-Te2X (X = S, Se), using first-principles calculations and study their potential applications in light harvesting devices. Both the monolayers possess high stability and semiconducting nature with an indirect band gap. The high carrier mobilities and excellent optical absorption of these monolayers make them potential candidates for solar conversion applications. We have proposed the type-II heterojunction solar cells and calculated their power conversion efficiencies (PCEs). The small conduction band offset and appropriate band gap of donor material in the case of ?-Te2S(S-Side)/?-Te2S(Te-Side) heterojunction results in a PCE of ?21%. In addition, the band alignments of these monolayers properly engulf the redox potentials of water. The overpotentials required to trigger hydrogen reduction (HER) and water oxidation (OER) half reactions reveal that HER and OER preferred acidic and neutral media, respectively. The calculated solar-to-hydrogen (STH) efficiencies of ?-Te2S (?-Te2Se) monolayers turn out to be ?13% (?12%), respectively, which implies their practical applications in water splitting. Thus, our work provides strong evidence regarding the potential applications of these materials in the field of light harvesting devices. � 2023 The Royal Society of Chemistry.
  • No Thumbnail Available
    Item
    Synergistic Effect of Crystallization Control and Defect Passivation Induced by a Multifunctional Primidone Additive for High-Performance Perovskite Solar Cells
    (American Chemical Society, 2022-12-22T00:00:00) Saykar, Nilesh G.; Iqbal, Muzahir; Ray, Asim K.; Mahapatra, Santosh K.
    The ionic nature of organic-inorganic metal halide perovskites endows intrinsic defects at the surface of the polycrystalline films. Simultaneous defect passivation during the growth of perovskite films could inhibit defect formation to a great extent. Herein, the anticonvulsant drug primidone (PRM) is demonstrated as a novel additive to control the crystallization and defect passivation of perovskites. The spectroscopic measurements support theoretical predictions showing the strong interaction between active functional groups and PbI2. An amount of PRM is tuned to obtain the perfect perovskite films with improved grain size and crystallinity than their control counterparts. Efficient PbI antisite defect passivation suppresses the non-radiative recombinations, resulting in higher luminance intensity and significantly longer charge carrier lifetimes. The PRM-modified perovskite solar cells (PSCs) show a power conversion efficiency (PCE) of 18.73%, much higher than that of control PSCs (16.62%). The ambient stability of PRM-modified PSCs is meritoriously increased compared to control PSCs. The PRM-modified PSCs show stability retention of up to 85% of the initial PCE after 1000 h, while control PSCs retain only 25% of the initial PCE after 550 h. The multifunctional defect passivation approach with the PRM additive shows the effective way for the efficiency and stability improvement of PSCs. � 2022 American Chemical Society.