Search

Converting non‐visual light into photocurrent while maintaining high visual transparency is vital for semitransparent organic solar cells (ST‐OSCs) application, yet often challenging over insufficient invisible light‐harvesting. Herein, spectrally selective optical manipulation for ST‐OSCs with high visual light transparency and full‐spectral non‐visual light reflection is proposed by matching the optical admittance of ultrathin Ag films using ZnS and MgF2. The reflection of optically enhanced ST‐OSCs at the spectral region beyond the human eye's response spectrum is improved and the transmission in the visual region is simultaneously enhanced. By further integrating an anti‐reflective structure, the optimal structure boosts the average visible transmittance and power conversion efficiency of ST‐OSCs to 44.3% and 12.6%, respectively, yielding a record light utilization efficiency of 5.6%. Corresponding flexible ST‐OSCs with high mechanical stability implies that this work provides a facile and universal strategy for ST‐OSCs aiming at building integrated photovoltaics. [ABSTRACT FROM AUTHOR]

Photodiode‐type solar‐blind photodetectors (SBPDs) with the self‐powered feature hold great promise for applications in unattended secure communication, flame detection, and missile warning. However, the responsivity of SBPDs is usually limited due to the severe solar‐blind (SB) light extinction in substrates and charge transport layers. Herein, a spectrally selective hole extraction structure (SHE) is proposed for high‐efficiency perovskite SBPDs. The SHE consisting of a tandem Fabry–Perot cavity and energy‐level‐matched hole transport layer endows the device with narrowband absorption in the SB region and optimized charge extraction capability from the CsPbI2Br perovskite. The optimized SHE exhibits a peak transmittance of 27% at 255 nm and a half maximum at full width of 28 nm. Under SB light illumination, the champion device achieves a responsivity of 56.20 mA W−1 and a detectivity (D*) of 2.86 × 1013 Jones, which are the record values among the reported results. The approach demonstrated here paves the way for the optical and electrical design of perovskite photodetectors with spectrally selective detection. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional (quasi‐2D) perovskites are emerging as efficient emitters in blue perovskite light‐emitting diodes (PeLEDs), while the imbalanced crystallization of the halide‐mixed system limits further improvements in device performance. The rapid crystallization caused by Cl doping produces massive defects at the interface, leading to aggravated non‐radiative recombination. Meanwhile, unmanageable perovskite crystallization is prone to facilitate the formation of nonuniform low‐dimensional phases, which results in energy loss during the exciton transfer process. Here, we propose a multifunctional interface engineering for nucleation and phase regulation by incorporating the zwitterionic additive potassium sulfamate into the hole transport layer. By using potassium ions (K+) as heterogeneous nucleation seeds, finely controlled growth of interfacial K+‐guided grains is achieved. The sulfamate ions can simultaneously regulate the phase distribution and passivate defects through coordination interactions with undercoordinated lead atoms. Consequently, such synergistic effect constructs quasi‐2D blue perovskite films with smooth energy landscape and reduced trap states, leading to pure‐blue PeLEDs with a maximum external quantum efficiency (EQE) of 17.32 %, spectrally stable emission at 478 nm and the prolonged operational lifetime. This work provides a unique guide to comprehensively regulate the halide‐mixed blue perovskite crystallization by manipulating the characteristics of grain‐growth substrate. [ABSTRACT FROM AUTHOR]

Heating is a knotty factor contributing to device degradation of flexible organic solar cells (FOSCs), and thermal regulation plays a crucial role in the realization of long operational lifetime. Herein, a passive cooling strategy for stable FOSCs is proposed by boosting the optical‐thermal radiative transfer to reduce the insufficient thermal dissipation and the elevated temperature caused by irradiation‐induced heating, while retaining their flexibility and portability. A spectrally selective coupling structure consisting of subwavelength hemisphere pattern and distributed Bragg reflector is integrated into FOSCs to collectively enhance out‐coupling of infrared radiation and limit near‐infrared absorption‐induced heat generation, leading to a reduced heat power intensity of 292.5 W cm−2 and the decreased working temperature by 9.6 °C under outdoor sunlight irradiation. The D18:Y6:PC71BM‐based FOSCs achieve a power conversion efficiency of over 17% with a prolonged T80 lifetime as long as one year under real outdoor working conditions. These results represent a new opportunity for enhancing the operational stability of FOSCs. [ABSTRACT FROM AUTHOR]

Semitransparent organic solar cells (STOSCs) hold great promise for applications ranging from building‐integrated photovoltaics to portable electronic devices, yet often challenging over the realization of color tunability. The structural colors generated by microcavity, subwavelength grating, or photonic crystals are highly dependent on the viewing angle, which limits the application of STOSCs in real scenarios. Herein, the spectrally selective substrates consisting of silica spheres‐based amorphous photonic crystals (APCs) are proposed to unify the optical spectra of STOSCs at different viewing angles. By optimizing the periodicity of APCs, STOSCs exhibit viewing‐angle‐independent reflection with colors varying from blue to pink. The synergetic interplay between the reflection of APCs and the absorption of active layer results in the Janus optical effect that the transmitted light is fixed at blue regardless of the reflected color. The STOSCs on flexible plastic retain the stable color even at bending state. These results pave the way for the potential application of colorful solar photovoltaic glass curtains. [ABSTRACT FROM AUTHOR]

Using narrow bandgap nonfullerene acceptors (NFAs) can broaden the absorption spectrum of organic solar cells (OSCs) to the near‐infrared region. However, the simultaneously decreased extinction coefficient of the active layer at the blue region results in inevitable light escaping and energy loss. Herein, a blazed grating‐based device configuration consisting of a patterned rear electrode is employed to compensate for the low absorption of nonfullerene OSCs. Experimental results reveal that the normal incidence light, especially blue light, that bounces off the patterned rear electrode is concentrated in a large tilted angle and subsequently trapped in waveguide mode. Along with the excitation of surface plasmon polariton, the structured nonfullerene OSCs using a new‐designed PM6:M36 active layer obtain the broadband absorption enhancement with 1.5 times increase at the blue region. The optimized device achieves an 8.95% increase in photocurrent and a champion power conversion efficiency of approaching 18%, which is the highest reported value among all the devices based on A‐D‐A type NFAs. [ABSTRACT FROM AUTHOR]

Background: Percutaneous radiofrequency ablation (RFA) is used as a first‐line treatment for colorectal liver metastases that recur after first liver resection in our institution. We aim to evaluate its therapeutic efficacy compared to repeated surgical resection. Methods: A retrospective review was performed in 104 patients treated with curative intent for resectable recurrent colorectal liver metastases. Results: Sixty‐one patients underwent RFA and 43 patients underwent surgery. The overall recurrence rates were 82% in the RFA group and 65.1% in the resection group (P = 0.05). The local recurrence rate on a lesion‐basis was markedly higher after RFA than that after resection (16.7% versus 7.3%, P = 0.04). The difference remained significant in patients with a maximum lesion diameter >3 cm (24.5% versus 7.6%, P = 0.01). RFA treatment was independently associated with recurrence on multivariate analyses (P = 0.01). 69.7% of RFA patients and 42.6% of surgery patients with intrahepatic recurrence were amenable to repeated local treatment (P = 0.05), leading to the equivalent actuarial 3‐year progression free survival rates (RFA: 29.1% versus Resection: 33.1%, P = 0.48) and 5‐year overall survival rates in the two treatment groups (RFA: 33% versus Resection: 28.4%, P = 0.36). Conclusions: Surgery remains the treatment of choice for resectable recurrence. RFA may offer similar benefit in selected patients. [ABSTRACT FROM AUTHOR]

Aim The prognostic value of the newly raised objective liver function assessment tool, the albumin-bilirubin (ALBI) grade, in patients with hepatocellular carcinoma has not been fully validated. We aimed to compare the performance of ALBI grade with the specific Child-Pugh (C-P) score in predicting prognosis in this study. Methods The clinical data of 491 C-P class A patients who underwent liver resection as initial therapy from January 2000 to December 2007 in Cancer Hospital, Chinese Academy of Medical Sciences (Beijing, China) were retrospectively analyzed. The prognostic performances of ALBI and C-P score in predicting the short- and long-term clinical outcomes were compared. Results The ALBI score gained a significantly larger area under the receiver operating characteristic curve for predicting the occurrence of severe postoperative complications than that of C-P score. With a median follow-up of 57 months, the 1-year, 3-year, and 5-year overall survival rates of the patients were 92.1%, 65.8%, and 45.2%, respectively. Tumor number, tumor size, and ALBI grade were proved to be the independent prognostic factors for overall survival in the multivariate analysis. Prognostic performance was shown to be better for ALBI grade when it was compared to C-P score in terms of both the Akaike information criterion value and χ2 value of likelihood ratio test. Conclusions The ALBI grade, which was featured by simplicity and objectivity, gained a superior prognostic value than that of C-P grade in patients with hepatocellular carcinoma who underwent liver resection. Future well-designed studies with larger sample sizes are warranted. [ABSTRACT FROM AUTHOR]