Core Insights - China's next-generation photovoltaic technology has made significant progress with the development of a perovskite tandem solar cell achieving a power conversion efficiency of over 30%, as published in the prestigious journal Nature on October 28 [1][2] Group 1: Technological Advancements - The research teams from Nanjing University and the National Defense Science and Technology Innovation Research Institute utilized terahertz technology for precise, non-destructive detection of carrier transport behavior in perovskite solar cells [1] - The newly developed perovskite tandem solar cell has achieved a power conversion efficiency of 30.1%, marking the first time this efficiency threshold has been surpassed for such cells [2] Group 2: Research Findings - The study identified that the interface between the perovskite light-absorbing layer and the hole transport layer is a significant area for carrier loss [1] - A dipole passivation layer was designed to facilitate carrier movement from the perovskite layer to the hole transport layer, effectively reducing losses [1] Group 3: Performance Metrics - Experimental data showed that the carrier mobility of the passivated perovskite films increased by over 68%, and the carrier diffusion length extended by nearly 30% [2] - The new perovskite tandem solar cell has been certified by an international third-party organization and is now included in the International Solar Cell Efficiency Table [2]

Core Viewpoint - The development of all-perovskite tandem solar cells, which combine wide and narrow bandgap perovskite sub-cells, represents a significant advancement in next-generation photovoltaic technology, offering high efficiency and low cost [1]. Group 1: Nanjing University Research - A team from Nanjing University has developed an all-perovskite tandem solar cell with a power conversion efficiency of 30.1%, marking the first time that the efficiency of polycrystalline thin-film solar cells has exceeded 30% [3]. - The research utilized a dipole passivation strategy to enhance charge transport and reduce losses at the interface between the perovskite light-absorbing layer and the hole transport layer [3]. - Experimental data showed that the mobility of total carriers increased by over 68%, and the carrier diffusion length extended by nearly 30% after passivation treatment [3]. Group 2: Shanghai Jiao Tong University Research - A research team from Shanghai Jiao Tong University introduced a novel "matrix-confined molecular layer" for the hole transport layer, overcoming intrinsic limitations of traditional self-assembled monolayer systems [4]. - This new technology path addresses issues of film uniformity and interface stability in the preparation of perovskite photovoltaic modules [4]. - The collaboration with CATL's 21C Innovation Laboratory resulted in a large-size perovskite photovoltaic module (1m×2m) achieving a power conversion efficiency exceeding 20%, setting a world record in the field [4].

Core Viewpoint - The research presents a breakthrough in all-perovskite tandem solar cells with a record power conversion efficiency (PCE) of 30.6% through the implementation of a dipolar passivation strategy [3][6]. Group 1: Research Findings - The study developed all-perovskite tandem solar cells utilizing dipolar passivation, achieving a record PCE of 30.6% [3]. - The dipolar passivation strategy effectively reduced the trap density at the buried interface of mixed Pb-Sn perovskite, allowing for precise energy level alignment at the HTL/perovskite interface [5]. - This strategy enhanced Ohmic contact, facilitating efficient hole injection into the HTL while repelling electrons at the HTL/Pb-Sn perovskite interface [5]. Group 2: Performance Metrics - The carrier diffusion length was increased to 6.2 μm, resulting in a significant PCE improvement of the Pb-Sn perovskite solar cell to 24.9%, with an open-circuit voltage (Voc) of 0.911 V, a short-circuit current density (Jsc) of 33.1 mA cm⁻², and a fill factor (FF) of 82.6% [5]. - The dipolar passivation also alleviated contact losses caused by the interconnection layer of the tandem device, pushing the PCE of the all-perovskite tandem solar cell to 30.6%, with a certified steady-state efficiency of 30.1% [6].