Although the efficiencies of all-perovskite tandem solar cells have surpassed 26%, further advancement of device performance is constrained by the large photovoltage deficit in wide-band-gap perovskite subcells. Meanwhile, state-of-the-art charge recombination layers incorporate an additional thin metal film (Au or Ag), which not only complexes device fabrication but induces parasitic optical losses. Here, we first fabricate efficient wide-band-gap perovskite solar cells (PSCs) with by suppressing nonradiative losses both in bulk material and at interface. The prepared PSCs with a band gap of 1.71 eV yield an impressive open-circuit voltage (V OC) of 1.27 V, giving a small V OC deficit of 0.44 V and an efficiency of 20.8%. We then fabricate monolithic all-printed perovskite tandem devices by constructing a metal-free recombination layer, which yields an efficiency of 23.65% and a high V OC of 2.05 V. This work offers a simple yet effective charge recombination architecture for advancing the performance of all-perovskite tandem devices.

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Thin films of tin–lead alloyed perovskites are drawing growing attention, mainly owing to their tunable bandgaps in delivering efficient single‐ and multi‐junction photovoltaic devices. The rapid efficiency advancement of Sn–Pb perovskite devices has been dependent primarily on improving the crystal quality of perovskite films via retarding oxidation of Sn2+. Herein, it is demonstrated that in addition to obtaining high‐quality Sn–Pb perovskite thin films, reducing nonradiative recombination losses at interfaces is equally important for realizing efficient solar cells. An aromatic amine is first introduced to passivate the grain boundary in printed Sn–Pb perovskite films, which boosts the open‐circuit voltage (V OC) of the solar devices from 700 to 766 mV. Further enhancement of the V OC to 814 mV and finally to 837 mV is realized by forming a 2D/3D‐layered heterojunction and doping the hole extraction layer with a polyelectrolyte, respectively, benefiting from the largely suppressed nonradiative recombination losses at interfaces. Eventually, the mixed Sn–Pb perovskite devices with a bandgap of ≈1.27 eV yield a high efficiency of 19.06% and in parallel show improved shelf and light‐soaking stability.