Progress in Photovoltaics最新文献

The poor crystal quality inside an absorber layer and the presence of various harmful defects are the main obstacles restricting the properties of Cu₂ZnSn (S, Se)₄ (CZTSSe) thin-film solar cells. Cation doping has attracted considerable research attention as a viable strategy to overcome this challenge. In this paper, based on Sb-substituted CZTSSe system, we prove that Ag partially substituting Cu may be a feasible strategy. After a series of characterization of the films, it was discovered that the crystal quality and crystallinity of the films were further improved by introducing Ag into Cu₂Zn(Sb, Sn) (S, Se)₄ (CZTSSSe), and the concentrations of Cu_Zn accepter defects and 2[Cu_Zn + Sn_Zn] defect clusters were effectively inhibited. At the same time, the carrier concentration is increased. The results show that when the Ag doping ratio is 15%, the photovoltaic conversion efficiency (PCE) reaches 8.34%, compared with the single-doped Sb element, the efficiency is increased by 24%. For the first time, this study investigates the collaborative effect of Sb, Ag dual-cation substitution in CZTSSe. The solar cell performance enhancement mechanism offers new potential for the advancement of CZTSSe thin-film solar cell technology in the future.

Over the past decade, silicon solar cells with carrier-selective passivating contacts based on polysilicon capping an ultra-thin silicon oxide (commonly known as TOPCon or POLO) have demonstrated promising efficiency potentials and are regarded as an evolutionary upgrade to the PERC (passivated emitter and rear contact) cells in manufacturing. The polysilicon-based passivating contacts also exhibit excellent gettering effects that relax the wafer and cleanroom requirements to some extent. In this work, we experimentally explore the impact of bulk iron contamination and polysilicon gettering on the passivation quality of the polysilicon/oxide structure and the resulting solar cells performance. Results show that both n- and p-type polysilicon/oxide passivating contacts are not affected by iron gettering, demonstrating robust and stable passivation quality. However, for a very high bulk iron contamination (1 × 10¹³ cm⁻³), the accumulated iron in the p-type lightly boron-doped emitter in crystalline silicon would degrade the emitter saturation current density. This can cause a reduction in both open-circuit voltage and short-circuit current. Meanwhile, this very high iron content (1 × 10¹³ cm⁻³) can further degrade the fill factor and temperature coefficient of the cells. On the other hand, for an initial iron content of 2 × 10¹² cm⁻³, which should be well above the iron level in the current industrial Czochralski silicon wafers, the resulting cells demonstrate similar performance as the control group with no intentional iron contamination. This work brings attention to both the benefits of polysilicon gettering effects as well as the potential degradation due to the accumulation of metal impurities in the p-type emitter region.

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since July 2024 are reviewed.

This paper presents an outdoor performance monitoring method for degradation studies of perovskite modules, focusing on a large-area perovskite module (81.9 cm²) over a long-term monitoring campaign. The module underwent an industrial lamination process to prevent long-term degradation from environmental factors. The characterization procedure involved degradation correction and determining the temperature coefficients and electrical parameters of the module using initial days of measurements. The results demonstrated temperature coefficients for I_sc, V_oc, and P_m (α′, β′, and γ) of −0.071%·K⁻¹, −0.119%·K⁻¹, and −0.113%·K⁻¹, respectively, indicating a minimal temperature influence on this technology compared with conventional ones. Using this coefficient, the STC electrical parameters were retrieved from 1-min power output data, resolving the uncertainty of the indoor/outdoor IV curve measurements caused by the curve scan direction (JV hysteresis effect). We also highlight the initial remarkable capacity recovery effect of almost 16% during the first 2 days of operation. Additionally, a procedure that includes the IV curves analysis taken every 10 min and their translation to standard conditions has been implemented to evaluate the degradation of the module over the long-term outdoor campaign. The results show three different trends over the period.