Pd(II)/Pd(IV) redox shuttle to suppress vacancy defects at grain boundaries for efficient kesterite solar cells.

Charge loss at grain boundaries of kesterite CuZnSn(S, Se) polycrystalline absorbers is an important cause limiting the performance of this emerging thin-film solar cell. Herein, we report a Pd element assisted reaction strategy to suppress atomic vacancy defects in GB regions. The Pd, on one hand in the form of PdSe compounds, can heterogeneously cover the GBs of the absorber film, suppressing Sn and Se volatilization loss and the formation of their vacancy defects (i.

Controlling Selenization Equilibrium Enables High-Quality Kesterite Absorbers for Efficient Solar Cells.

Kesterite CuZnSn(S, Se) is considered one of the most competitive photovoltaic materials due to its earth-abundant and nontoxic constituent elements, environmental friendliness, and high stability. However, the preparation of high-quality Kesterite absorbers for photovoltaics is still challenging for the uncontrollability and complexity of selenization reactions between metal element precursors and selenium. In this study, we propose a solid-liquid/solid-gas (solid precursor and liquid/vapor Se) synergistic reaction strategy to precisely control the selenization process.

Toward High Efficient Cu ZnSn(S ,Se ) Solar Cells: Break the Limitations of V and FF.

Increasing the fill factor (FF) and the open-circuit voltage (V ) simultaneously together with non-decreased short-circuit current density (J ) are a challenge for highly efficient Cu ZnSn(S,Se) (CZTSSe) solar cells. Aimed at such target in CZTSSe solar cells, a synergistic strategy to tailor the recombination in the bulk and at the heterojunction interface has been developed, consisting of atomic-layer deposited aluminum oxide (ALD-Al O ) and (NH ) S treatment. With this strategy, deep-level Cu defects are converted into shallower V defects and improved crystallinity, while the surface of the absorber is optimized by removing Zn- and Sn-related impurities and incorporating S.

Accelerating defect analysis of solar cells via machine learning of the modulated transient photovoltage.

Fast and non-destructive analysis of material defect is a crucial demand for semiconductor devices. Herein, we are devoted to exploring a solar-cell defect analysis method based on machine learning of the modulated transient photovoltage (m-TPV) measurement. The perturbation photovoltage generation and decay mechanism of the solar cell is firstly clarified for this study.

Oxygen Content Modulation Toward Highly Efficient SbSe Solar Cells.

Vapor-transport deposition (VTD) method is the main technique for the preparation of SbSe films. However, oxygen is often present in the vacuum tube in such a vacuum deposition process, and SbO is formed on the surface of SbSe because the bonding of Sb-O is formed more easily than that of Sb-Se. In this work, the formation of SbO and thus the carrier transport in the corresponding solar cells were studied by tailoring the deposition microenvironment in the vacuum tube during SbSe film deposition.

Ge Bidirectional Diffusion to Simultaneously Engineer Back Interface and Bulk Defects in the Absorber for Efficient CZTSSe Solar Cells.

Aiming at a large open-circuit voltage (V ) deficit in Cu ZnSn(S,Se) (CZTSSe) solar cells, a new and effective strategy to simultaneously regulate the back interface and restrain bulk defects of CZTSSe absorbers is developed by directly introducing a thin GeO layer on Mo substrates. Power conversion efficiency (power-to-efficiency) as high as 13.14% with a V of 547 mV is achieved for the champion device, which presents a certified efficiency of 12.

Two-Step Annealing CZTSSe/CdS Heterojunction to Improve Interface Properties of Kesterite Solar Cells.

The post-heating treatment of the CZTSSe/CdS heterojunction can enhance the interfacial properties of kesterite CuZnSn(S,Se) (CZTSSe) solar cells. In this regard, a two-step annealing method was developed to enhance the heterojunction quality for the first time. That is, a low-temperature (90 °C) process was introduced before the high-temperature treatment, and 12.