single-junction PVSCs and a champion efficiency of 29.5% realized for perovskitebased tandem solar cells. [1][2][3][4][5][6][7] Meanwhile, impressive strides have been made to enhance their stability and scale up, [8][9][10][11][12][13][14][15][16][17][18][19] which improve their feasibility to be used for next-generation photovoltaics (PVs). Nonetheless, the toxicity of lead-containing components in high-performance PVSCs is the main hurdle that impedes their potential deployment. [20][21][22] When damaged by irresistible natural factors or external forces, [23,24] the toxic lead in PVSCs readily leaches into the environment, posing a threat to human health. [25,26] Recently, physical or chemical barrier layers were employed to suppress the potential lead leakage in PVSCs. [27][28][29][30] For instance, a self-healing epoxy resin had been applied as a physical barrier layer to minimize the direct exposure of perovskite to the rain for suppressing the lead leakage. [23] Cation exchange resins had been used as lead-absorbing materials to efficiently trap lead through the strong chemical bonding between lead and sulfonate group. [27,28] Moreover, the phosphoric acid based lead absorbing materials had also been employed to prevent the lead leakage. [29] In all these reports, they focused on PVSCs based on rigid substrates for outdoor applications without mentioning the even more challenging task of preventing lead leakage in flexible devices. To have the capability of effectively trapping Pb 2+ in flexible devices to a safe-to-use level is very critical because most of these devices are used in applications related to our daily life, which poses a direct threat to human health.According to the European Union and United States (US) regulations for restricted toxic substances concentration on the perweight basis, the lead concentration from a flexible perovskite PV device is estimated to be more than 50 times higher than that from the rigid device due to the lighter weight of flexible substrates, making the prevention of lead leakage in flexible PVSCs more challenging. [31] Moreover, the lead trapping materials should not damage the light weight, flexibility, performance, and stability of flexible perovskite solar modules (PVSMs) for commercial deployment. To achieve regulatory compliance for flexible devices, it is imperative to develop effective lead-adsorbing materials with good flexibility, light weight, and high lead adsorption capacity. Graphene aerogels (GA) featured with excellent mechanical strength and flexibility, light weight, large specific area, high adsorption capacity, and low cost are ideal adsorbentsThe potential leakage of lead from degraded perovskite photovoltaics poses a threat to the ecosystem and human health, which is a severe hurdle for their commercialization, especially for flexible modules that are often integrated in applications used in daily living. To trap the lead from degraded flexible perovskite solar modules (PVSMs), sulfonated graphene aerogels mixed with polydimethylsiloxane are ...
