1T-Rich 2D-WS₂ as an interfacial agent to escalate photo-induced charge transfer dynamics in dopant-free perovskite solar cells

Abstract

The rapid scientific surge in halide perovskite solar cells (PSCs) is owing to their solution processability and high power conversion efficiency, however, the deficiency in the photo-induced charge transfer dynamics...

Molecular Interface Engineering via Triazatruxene‐Based Moieties/NiOx as Hole‐Selective Bilayers in Perovskite Solar Cells for Reliability

“…J ph and V eff follow the relationships of J ph = J L − J D and V eff = V 0 − V , respectively, where J L is current density under illumination, J D is current density in the dark, V 0 is the compensation voltage defined at J ph = 0, and V is the external bias voltage. [ 6 ] Notably, the PSC based on DTT‐EHDI 2 displays a rapid saturation of photocurrent at a relatively low V eff of 0.207 V when compared with that of the control device (0.376 V), which we attribute to the effective charge separation and extraction behavior in the PSC on interfacial layer placement. The maximum exciton generation rate ( G max ) is a crucial factor in PSCs, which governs the charge dissociation and collection and thus the saturation current density ( J sat ), following the relation of J sat = eLG max (where, e and L are elementary charges and the thickness of the perovskite layer, respectively).…”

“…Figure a shows the Nyquist plot at 950 mV applied bias voltage in the dark which is fitted with the equivalent circuit model of R s + R ctr /CPE1 + R rec /CPE2 (Figure S13, Supporting Information), where R s , R ctr , and R rec represent single‐series resistance, charge transfer resistance, and charge recombination resistance at the interface between perovskite/HTL, respectively. [ 6,47 ] R ctr was extracted from the high‐frequency region, while R rec was determined in the low‐frequency region ( Table 2 ). Two constant phase elements related to carrier diffusion in perovskite and selective layers were assigned as CPE1 and CPE2.…”

“…The leakage current represented by the semilogarithmic curve at the negative bias potential of the DTT‐EHDI 2 ‐based PSCs is much lower than that of the control PSC, signaling that the higher J SC obtained is through suppressing recombination. By fitting the linear part of the curve with the Shockley equation that is given by [ 6,49 ] where J D is the dark current density, J 0 is the saturation current density, V is the applied voltage, q is the electron charge, K B is the Boltzmann constant, and T is the temperature, we extracted the ideality factor ( n id ) of the PSCs. The estimated J 0 and n id for the PSCs without DTT‐EHDI 2 were 9.35 × 10 −6 mA cm −2 and 3.17, respectively, whereas those for the PSCs with the DTT‐EHDI 2 interface layer were 5.07 × 10 −7 mA cm −2 and 2.58, respectively.…”

“…[ 4,5 ] The notable strategies have been devoted including new device architectures, perovskite compositional and interfacial engineering, and used of rational materials derived from inorganic oxides, organic molecules, and 2D materials to tune PSCs’ electro‐optical properties and subsequently boost PV performance and stability. [ 5–11 ] Typically, PSCs are composed of a light‐harvesting perovskite as an active layer sandwiched between two selective charge‐transporting layers, namely the hole‐transporting layer (HTL) and the electron‐transporting layer (ETL) for positive and negative charge extraction, respectively. These charge‐transporting layers are rationally selected by taking into consideration the charge mobility, energy‐level alignment, and compatibility with the perovskite absorber.…”

Advanced Ru/Ni/WC@NPC Multi‐Interfacial Electrocatalyst for Efficient Sustainable Hydrogen and Chlor‐Alkali Co‐Production

“…The second pair of peaks at high binding energies of 36.97 and 34.79 eV arising from the unavoidable surface oxidation of Ru/Ni/WC@NPC and attributed to W +6 4f 5/2 and 4f 7/2 . [ 18 ] The XPS spectrum of N 1s (Figure 3g) unearths three typical N fitted peaks at 401.02, 399.47, and 397.01 eV correspond to the nitrogen sources of graphitic N, pyrrolic N, and pyridinic N, respectively. [ 19 ] Similarly, in the high‐resolution P 2p XPS spectrum (Figure 3h), three peaks at 129.44, 132.13, and 134.81 eV can be assigned to P–C bonds (P 2p 3/2 , P 2p 1/2 ) and P–O bond (O–P), respectively, [ 20 ] suggesting the success of N and P dopants into the carbon nanosheets.…”