Summary The 2021 Mw7.4 Maduo earthquake occurred on the Jiangcuo fault within the Bayan Har block in eastern Tibet. It is a rather unique event, and attests that large earthquakes can occur in the interior of major tectonic blocks within the Tibetan plateau. By processing GPS data observed in the eastern Tibet region, we produce a dataset documenting three-dimensional coseismic displacements of the Maduo earthquake. Using the dataset to constrain a coseismic slip model, we find that the earthquake ruptured a nearly vertical fault about 170 km in length, with ∼90 per cent of the moment released in the shallow layer above 20 km depth. The maximum slip of ∼3.6 m occurred near the surface around a bend in the east segment of the fault. The overall seismic moment release is 1.82 × 1020 N·m, and equivalent to Mw7.4. Driven by the eastward extrusion of the Tibetan plateau, the deformation field in eastern Tibet is dominated by left-lateral shear, with the strikes of the tectonic faults rotating clockwise from west to east along with the shear stress orientation. This deformation pattern explains the mechanisms of earthquakes along block boundary faults, as well as the ones on faults within the blocks. The Jiangcuo fault is located ∼70 km south of the East Kunlun fault and could be connected to the Kunlun Mountain Pass fault to its WNW which ruptured during the 2001 Kokoxili earthquake, and a seismic gap of ∼240 km long between the two faults is worth special attention for its increased earthquake potential.

The polymerized small-molecule acceptors have attracted great attention for application as polymer acceptor in all-polymer solar cells recently. The modification of small molecule acceptor building block and the π-bridge linker is an effective strategy to improve the photovoltaic performance of the polymer acceptors. In this work, we synthesized a new polymer acceptor PG-IT2F which is a modification of the representative polymer acceptor PY-IT by replacing its upper linear alkyl side chains on the small molecule building block with branched alkyl chains and attaching difluorene substituents on its thiophene π-bridge linker. Through this synergistic optimization, PG-IT2F possesses more suitable phase separation, increased charge transportation, better exciton dissociation, lower bimolecular recombination, and longer charge transfer state lifetime than PY-IT in their polymer solar cells with PM6 as polymer donor. Therefore, the devices based on PM6:PG-IT2F demonstrated a high power conversion efficiency of 17.24%, which is one of the highest efficiency reported for the binary all polymer solar cells to date. This work indicates that the synergistic regulation of small molecule acceptor building block and π-bridge linker plays a key role in designing and developing highly efficient polymer acceptors.

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