The exceptional photoelectric performance and high compatibility of perovskite materials render perovskite solar cells highly promising for extensive development, thus garnering significant attention. In perovskite solar cells, the hole transport layer plays a crucial role. For the commonly employed organic small molecule hole transport material Spiro-OMeTAD, a certain period of oxidation treatment is required to achieve complete transport performance. However, this posttreatment oxidation processes typically rely on ambient oxidation, which poses challenges in terms of precise control and leads to degradation of the perovskite light absorption layer. This approach fails to meet the demands for high efficiency and stability in practical application. Herein, the mechanism of ultrafast laser on Spiro-OMeTAD and the reaction process for laser-induced oxidation of it are investigated. PbI₂ at Perovskite/Spiro-OMeTAD interface breaks down to produce I₂ upon ultrafast laser irradiation and I₂ promote the oxidation process. Through the laser irradiation oxidation processing, a higher stability of perovskite solar cells is achieved. This work establishes a new approach toward oxidation treatment of Spiro-OMeTAD.

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal resistance. It is a promising idea to shape inorganic materials in three-dimensional (3D) forms to reduce their weight while maintaining high mechanical properties. A popular strategy for the preparation of 3D inorganic materials is to mold the organic–inorganic hybrid photoresists into 3D micro- and nano-structures and remove the organic components by subsequent sintering. However, due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists, it remains a huge challenge to attain isotropic shrinkage during sintering. Herein, we demonstrate the isotropic sintering shrinkage by forming the consecutive –Si–O–Si–O–Zr–O– inorganic backbone in photoresists and fabricating 3D glass–ceramic nanolattices with enhanced mechanical properties. The femtosecond (fs) laser is used in two-photon polymerization (TPP) to fabricate 3D green body structures. After subsequent sintering at 1000°C, high-quality 3D glass–ceramic microstructures can be obtained with perfectly intact and smooth morphology. In-suit compression experiments and finite-element simulations reveal that octahedral-truss (oct-truss) lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending, indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices. 3D printing of such glasses and ceramics has significant implications in a number of industrial applications, including metamaterials, microelectromechanical systems, photonic crystals, and damage-tolerant lightweight materials.

Because poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is water processable, thermally stable, and highly conductive, PEDOT:PSS and its composites have been considered to be one of the most promising flexible thermoelectric materials. However, the PEDOT:PSS film prepared from its commercial aqueous dispersion usually has very low conductivity, thus cannot be directly utilized for TE applications. Here, a simple environmental friendly strategy via femtosecond laser irradiation without any chemical dopants and treatments was demonstrated. Under optimal conditions, the electrical conductivity of the treated film is increased to 803.1 S cm⁻¹ from 1.2 S cm⁻¹ around three order of magnitude higher, and the power factor is improved to 19.0 μW m⁻¹ K⁻², which is enhanced more than 200 times. The mechanism for such remarkable enhancement was attributed to the transition of the PEDOT chains from a coil to a linear or expanded coil conformation, reduction of the interplanar stacking distance, and the removal of insulating PSS with increasing the oxidation level of PEDOT, facilitating the charge transportation. This work presents an effective route for fabricating high-performance flexible conductive polymer films and wearable thermoelectric devices.