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Silicon heterojunction (SHJ) solar cells have garnered significant attention recently due to their excellent performance, benefiting from the outstanding passivation quality of intrinsic/doped hydrogenated amorphous silicon (a‐Si:H) bilayers. Herein, it is found that current injection at elevated temperatures can enhance the electrical performance of SHJ solar cells. The kinetics study clarifies that activation energy of 0.5 eV is obtained for this enhancement phenomenon. By using photoluminescence (PL) images, it is demonstrated that the performance enhancement can be mainly attributed to the reduction of electrically active defects. The underlying mechanism is focused on the diffusion and passivation effect of hydrogen, which could be valuable for understanding the kinetics of the current injection‐induced enhancement phenomenon in the SHJ cells. This approach serves as an alternative method of light soaking to reach the effect of performance enhancement of SHJ cells, making it more competitive in the photovoltaics industry. [ABSTRACT FROM AUTHOR]

Herein, it is demonstrated that low temperature current injection and annealing (CIA) treatment can cause evident improvements in open circuit voltage, short‐circuit current, and fill factor of tunnel oxide‐passivated contact (TOPCon) silicon solar cells, leading to a notable conversion efficiency gain (over 0.4% absolute at the best condition). The effects of injected current and annealing temperatures toward the improvement of electrical performance of the TOPCon solar cells are compared. The more evident increase in the electrical performance after the CIA treatment may come from the higher fill factor improvements, which can be induced by the change of contact resistance after the CIA treatment, the potential involvement of hydrogen is discussed. The CIA treatment can be a reliable approach to further enhance the conversion efficiency of TOPCon solar cells, which is of great significance for the global PV industry. [ABSTRACT FROM AUTHOR]

Herein, the degradation and regeneration processes of p‐type cast‐monosilicon passivated emitter rear contact solar cells are investigated, by taking open‐circuit voltage as a measure for the light‐ and elevated‐temperature‐induced degradation (LeTID) and regeneration extent. Degradation and regeneration are triggered by current injection and light soaking at the same temperatures. Then, an Arrhenius plot, derived from the proposed model, is used to extract the degradation and regeneration rate constants of LeTID during both current injection and light‐soaking processes. The activation energies of degradation processes are calculated to be (0.790 ± 0.064) and (0.828 ± 0.013) eV for current injection and light soaking, respectively. The corresponding activation energies for regeneration processes are (1.059 ± 0.112) and (1.179 ± 0.070) eV, respectively. Notably, the similar activation energies indicate that the root cause of the LeTID induced by current injection or light soaking is the same. In addition, an exponential dependence of the rate constants upon the injection current values during the whole degradation and regeneration cycle induced by current injection is observed. These results are not only significant for understanding the kinetics of LeTID but also can shed light on effective LeTID suppression method in the photovoltaic industry. [ABSTRACT FROM AUTHOR]

Graphene has attracted increasing attention due to its unique electrical, optical, optoelectronic, and mechanical properties, which have opened up huge numbers of opportunities for applications. An overview of the recent research on graphene and its derivatives is presented, with a particular focus on synthesis, properties, and applications in solar cells. [ABSTRACT FROM AUTHOR]

The ultraviolet-induced degradation (UVID), with losses of up to 11 % after 2000 h-exposure (Sinha et al., 2023) [1], impairs long-term stability of silicon heterojunction (SHJ) solar cells at present. However, the mechanism of UVID has remained only roughly understood till now. Herein, we shed light on the electrical properties of defects in SHJ solar cells to elucidate the underlying mechanism. Defect generation in SHJ solar cells after ultraviolet (UV) irradiation can be observed from photoluminescence (PL) images. Furthermore, we extract the density of states near Fermi level in hydrogenated amorphous silicon (a -Si:H) through analyzing carrier transport mechanism, and find the increment of state density induced by the UV irradiation. In conjunction with Fourier-transform infrared (FTIR) spectra, we ascribe the UV-induced defects to the rupture of Si–H and Si–H 2 bonds. Besides, the intersection point between Fermi levels of the c -Si and a -Si:H/ c -Si interface can be found shift toward valence band from admittance spectrum analysis, which is the cause of the higher interface state density based on the theory of Fermi energy dependent hydrogen diffusion energy. As a result, a potential mechanism of generation of recombination centers responsible for UVID in SHJ solar cells is proposed, which could provide insights into the possible solutions for UVID and enhance the long-term stability of SHJ solar cells. • We have qualitatively and quantitatively investigated the generation of induced defects during ultraviolet-induced degradation (UVID) process in silicon heterojunction (SHJ) solar cells. • The UV irradiation induce bond rupture of Si–H and Si–H 2 in hydrogenated amorphous silicon (a -Si:H) film, which brings about higher density of states near Fermi level. • The UV irradiation induce the shift of Fermi level position at the interface of a -Si:H/ c -Si, which decreases the formation enthalpy of H-related defects and leads to higher interface state density. [ABSTRACT FROM AUTHOR]