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The performance of perovskite solar cells (PSCs) is often constrained by significant open‐circuit voltage (VOC) losses attributed to non‐radiative recombination processes induced by detrimental trap states. Surface treatments using passivating ligands typically involve single active binding sites on perovskite, posing challenges for effective passivation. Here, an aromatic donor‐acceptor (D‐A) configured phthalocyanine treatment is proposed to aim at dual‐site passivation of uncoordinated lead ions and effective mitigation of shallow and deep‐level defects on the perovskite surface. The resulting benign p‐type surface facilitates a more favorable energy level alignment and reduces energetic mismatches at the perovskite/Spiro‐OMeTAD interface. Pc‐BTBC, with its aromatic D‐A configuration, demonstrated compatibility with various perovskite compositions. Optimized PSCs achieves a power conversion efficiency (PCE) of 25.15% and reduces the VOC deficit to 0.379 V. Furthermore, encapsulated devices exhibited enhanced stability under damp‐heat conditions (ISOS‐D‐2, 50% RH, 65°C) with a T92 of 1000 h and maintained maximum power point tracking under continuous light in ambient air at 65°C (ISOS‐L‐2). Notably, fabricated wide‐bandgap semitransparent PSCs (ST‐PSCs) achieved a PCE of 20.29%, while four‐terminal perovskite/silicon tandem solar cells (4T‐P/STSCs) demonstrated an efficiency of 29.38%. This study provides insights into minimizing VOC losses and represents significant progress toward commercializing perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

While colloidal quantum dot photovoltaic devices (CQDPVs) can achieve a power conversion efficiency (PCE) of ≈12%, their insufficient optical absorption in the near‐infrared (NIR) regime impairs efficient utilization of the full spectrum of visible light. Here, high‐efficiency, solution‐processed, hybrid series, tandem photovoltaic devices are developed featuring CQDs and organic bulk heterojunction (BHJ) photoactive materials for front‐ and back‐cells, respectively. The organic BHJ back‐cell efficiently harvests the transmitted NIR photons from the CQD front‐cell, which reinforces the photon‐to‐current conversion at 350–1000 nm wavelengths. Optimizing the short‐circuit current density balance of each sub‐cell and creating a near ideal series connection using an intermediate layer achieve a PCE (12.82%) that is superior to that of each single‐junction device (11.17% and 11.02% for the CQD and organic BHJ device, respectively). Notably, the PCE of the hybrid tandem device is the highest among the reported CQDPVs, including single‐junction devices and tandem devices. The hybrid tandem device also exhibits almost negligible degradation after air storage for 3 months. This study suggests a potential route to improve the performance of CQDPVs by proper hybridization with NIR‐absorbing photoactive materials. [ABSTRACT FROM AUTHOR]

Owing to their high efficiency, low-cost solution-processability, and tunable bandgap, perovskite solar cells (PSCs) made of hybrid organic-inorganic perovskite (HOIP) thin films are promising top-cell candidates for integration with bottom-cells based on Si or other low-bandgap solar-cell materials to boost the power conversion efficiency (PCE) beyond the Shockley-Quiesser (S-Q) limit. In this review, recent progress in such tandem solar cells based on the emerging PSCs is summarized and reviewed critically. Notable achievements for different tandem solar cell configurations including mechanically-stacked, optical coupling, and monolithically-integrated with PSCs as top-cells are described in detail. Highly-efficient semitransparent PSC top-cells with high transmittance in near-infrared (NIR) region are critical for tandem solar cells. Different types of transparent electrodes with high transmittance and low sheet-resistance for PSCs are reviewed, which presents a grand challenge for PSCs. The strategies to obtain wide-bandgap PSCs with good photo-stability are discussed. The PCE reduction due to reflection loss, parasitic absorption, electrical loss, and current mismatch are analyzed to provide better understanding of the performance of PSC-based tandem solar cells. [ABSTRACT FROM AUTHOR]

A new metal-oxide-based interconnecting layer (ICL) structure of all-solution processed metal oxide/dipole layer/metal oxide for efficient tandem organic solar cell (OSC) is demonstrated. The dipole layer modifies the work function (WF) of molybdenum oxide (MoO x ) to eliminate preexisted counter diode between MoO x and TiO2. Three different amino functionalized water/alcohol soluble conjugated polymers (WSCPs) are studied to show that the WF tuning of MoO x is controllable. Importantly, the results show that S-shape current density versus voltage ( J- V) characteristics form when operation temperature decreases. This implies that thermionic emission within the dipole layer plays critical role for helping recombination of electrons and holes. Meanwhile, the insignificant homotandem open-circuit voltage ( Voc) loss dependence on dipole layer thickness shows that the quantum tunneling effect is weak for efficient electron and hole recombination. Based on this ICL, poly(3-hexylthiophene) (P3HT)-based homotandem OSC with 1.20 V Voc and 3.29% power conversion efficiency (PCE) is achieved. Furthermore, high efficiency poly(4,8-bis(5-(2-ethylhexyl)-thiophene-2-yl)-benzo[1,2-b54,5-b9]dithiophene-alt alkylcarbonylthieno[3,4-b]thiophene) (PBDTTT-C-T)-based homotandem OSC with 1.54 V Voc and 8.11% PCE is achieved, with almost 15.53% enhancement compared to its single cell. This metal oxide/dipole layer/metal oxide ICL provides a new strategy to develop other qualified ICL with different hole transporting layer and electron transporting layer in tandem OSCs. [ABSTRACT FROM AUTHOR]

In article number 1500631, Fei Huang, Wallace C. H. Choy, and co‐workers address one of the main electrical issues of the interconnecting layer (ICL) in tandem organic solar cells by introducing a dipole material to modify the counter‐diode barrier between the hole transport layer (HTL) and the electron transport layer (ETL). This strategy contributes towards a general method to combine other HTL and ETL as the effective ICL. [ABSTRACT FROM AUTHOR]