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As a typical kind of high‐efficiency crystalline silicon (c‐Si) solar cell, amorphous/crystalline silicon heterojunction (SHJ) solar cell is stepping into mass production currently. It is of great significance to recover Ag from unqualified, broken, and end‐of‐life (EoL) SHJ solar cells. Herein, a facile method including alkaline chemical immersion and pyrolysis is developed. By immersing the solar cell into a sodium hydroxide (NaOH) aqueous solution for a period of time, Ag electrodes can be peeled off effectively. The increase of the concentration (Cs) and the temperature (Ts) of the NaOH solution shortens the peeling‐off time (tp) of the electrodes. It is deduced that the heated alkaline environment can accelerate the ester hydrolysis of the cured resin at the contact interface between Ag electrode and transparent conductive oxide (TCO) layer, which weakens the bonding strength of the Ag electrode. After cleaning, drying, and milling, the peeled‐off Ag electrodes are pyrolyzed in the air at 500 °C for 60 min to remove the cured resin completely. As a result, Ag powder is obtained with high purity over 99% and almost without mass loss since it is not involved in any chemical reaction during the whole recovery process. [ABSTRACT FROM AUTHOR]

• The effects of TeO 2 on the sintering of c-Si solar cell are systematically studied. • TeO 2 affects the morphology of the grids on the sintering process of Ag pastes. • TeO 2 promotes Ag pastes sintering and improves the conductivity of Ag grids. • TeO 2 promotes the growth of the Ag nanocrystallites in Ag/Si contact interface. • An optimal conversion efficiency of solar cells was acquired at TeO 2 content ∼40%. Glass frits, as a critical ingredient, plays an important role between Ag electrode and crystalline silicon (c-Si) solar cells and determines sintering properties of the silver paste and contact quality with c-Si solar cells. Here glass frits with different contents of TeO 2 are prepared and used to investigate the sintering process and effects of contact quality of Ag pastes on c-Si solar cells. Microstructures and electrical properties of the Ag/Si contact interface and performances of the resultant c-Si solar cells are characterized systematically. The results show that TeO 2 promotes the growth of Ag nanocrystallites in the glass layer between Ag grids and c-Si wafers, thus reduces the contact resistance of the Ag grids and improves the contact quality of the Ag/Si interfaces. Moreover, TeO 2 improves the densification and conductive performances of the Ag grids. However, excessive TeO 2 has a negative effect on the conductivity of the Ag grid due to the increased thickness of the glass layer. Based on the competing factors played by TeO 2 , the conversion efficiency is the highest at an optimized TeO 2 content ∼40%. [ABSTRACT FROM AUTHOR]

The structural, electrical and optical properties of molybdenum oxide (MoO x) thin films prepared by magnetron sputtering are studied with annealing temperature. The interface properties of silicon with the intrinsic amorphous silicon (a-Si:H(i)) and alumina (AlO x) passivation layers are investigated by the minority carrier lifetime and implied-V oc (iV oc). The AlO x shows the better passivation properties and thermal stability for the carrier-selective contact solar cells. The Ce-doped In 2 O 3 (ICO) is deposited on the surface of MoO x thin films. It is found that the optimized annealing temperature is 125 °C for the carrier selective contact solar cells with the a-Si:H(i) passivation layer. It could increase to 175 °C for the AlO x passivation layer. • Properties of MoO x thin films prepared by magnetic sputtering were studied. • Effect of annealing on the interface properties of silicon with different passivation layers is investigated. • AlO x showed the better passivation properties and thermal stability for CSC solar cells. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of H 2 O partial pressure on the chemical characteristic and optoelectrical properties of the indium tin oxide (ITO) films and the performance and stability of heterojunction (HJT) solar cells. The H 2 O with varying partial pressure from 2.72 × 10−5 Pa to 8.38 × 10−5 Pa is obtained from the residual gas in the magnetron sputtering device chamber. With the H 2 O partial pressure raises, the resistivity of ITO films increases from 3.6 × 10−4 Ω·cm to 5.3 × 10−4 Ω·cm, and the effective total transmittance improves slightly in the near-infrared region. The efficiency of HJT solar cells with ITO films deposited at high H 2 O partial pressure is lower due to the deterioration of fill factor (FF), even though the short circuit current (I sc) increased. Thus, the maximum HJT solar cell efficiency of 25.30% is achieved at low H 2 O partial pressure. In addition, the performance of HJT solar cells under a nitrogen environment without illumination was tracked. It is observed that the high cell efficiency obtained with low H 2 O partial pressure has a larger degradation, which is mainly derived from the FF degradation. [Display omitted] • Residual H 2 O partial pressure in chamber during ITO films deposition is monitored. • Properties of ITO films and HJT solar cells are investigated. • 25.30% high-efficiency HJT solar cell is prepared. • Degradation of HJT solar cells is tracked without illumination. [ABSTRACT FROM AUTHOR]

Tin-doped indium oxide (ITO) thin films were prepared at low substrate temperature by direct-current magnetron sputtering technology and applicated as the electrode of silicon heterojunction solar cells (HJT). The chemical, electrical and optical properties of ITO films deposited at different sputtering power are investigated. The optimized ITO films are applied as electrode of HJT solar cells, and the conversion efficiency of more than 25.22% is obtained. In addition, the passivated degradation resulting from ITO deposition is analyzed. The result shows that the degradation is recovered by the annealing process. Finally, the degradation of solar cell efficiency in dark nitrogen environment is tracked. It is found that the solar cells with the highest average conversion efficiency have poor stability, which is mainly attributed to the degradation of the fill factor. • The properties of Tin-doped indium oxide films are investigated. • 25.22% high-efficiency silicon heterojunction solar cell is prepared. • Passivated degradation after Tin-doped indium oxide is recovered by annealing. • Heterojunction solar cell prepared at high sputtering power has poor stability. [ABSTRACT FROM AUTHOR]