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We show by electron spin resonance (ESR) and Raman spectroscopies that the crystal phase transition of the lead-free double-perovskite Cs2AgBiBr6 has a profound symmetry-breaking effect on the high spin states of, for example, a transition-metal ion Fe3+ and the vibrational modes. It lifts their degeneracy when the crystal undergoes the cubic-tetragonal phase transition, splitting the six-fold degenerate S = 5/2 state of Fe3+ to three Kramer doublets and the enharmonic breathing mode T-g of the MBr6 octahedra (M = Ag, Bi, Fe) into E-g + A(g). The magnitudes of both spin and Raman line splitting are shown to directly correlate with the strength of the tetragonal strain field. This work, in turn, demonstrates the power of the ESR and Raman spectroscopies in probing structural phase transitions and in providing in-depth information on the interplay between the structural, spin, and vibrational properties of lead-free double perovskites, a newly emerging and promising class of materials for low-cost and high-efficiency photovoltaics and optoelectronics. ; Funding Agencies|Swedish Research CouncilSwedish Research Council [VR-2017-05285]; Linkoping University; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW 2019.0082]

Matched energy level alignment is a key requirement for efficient organic devices such as organic light-emitting diodes, photovoltaics, and field-effect transistors. The effect of thermal stress/annealing on energy level alignment and related properties of the devices are less discussed compared to the extensively explored effect on morphology and corresponding device performance. Here all polymer solar cells (all-PSCs) are employed to study thermal annealing effects on energy level alignment and the corresponding effect on the device properties of the all-PSCs. It is found that optimized energy level alignment can be achieved by thermal annealing. An interface dipole layer at the donor/acceptor interface is introduced by energy level realignment that assists charge generation by reducing geminate recombination so that the voltage loss is dramatically reduced, improving the performance of the all-PSCs. ; Funding Agencies|Knut and Alice Wallenberg Foundation project "Tail of the Sun"; Swedish Research CouncilSwedish Research Council [2016-05498]; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research [SE13-0060]; Swedish Energy AgencySwedish Energy Agency [45411-1]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO Mat LiU) [2009 00971]

Doping of organic semiconductors is a powerful tool to optimize the performance of various organic (opto)electronic and bioelectronic devices. Despite recent advances, the low thermal stability of the electronic properties of doped polymers still represents a significant obstacle to implementing these materials into practical applications. Hence, the development of conducting doped polymers with excellent long-term stability at elevated temperatures is highly desirable. Here, we report on the sequential doping of the ladder-type polymer poly-(benzimidazobenzophenanthroline) (BBL) with a benzimidazole-based dopant (i.e., N-DMBI). By combining electrical, UV-vis/infrared, X-ray diffraction, and electron paramagnetic resonance measurements, we quantitatively characterized the conductivity, Seebeck coefficient, spin density, and microstructure of the sequentially doped polymer films as a function of the thermal annealing temperature. Importantly, we observed that the electrical conductivity of N-DMBI-doped BBL remains unchanged even after 20 h of heating at 190 degrees C. This finding is remarkable and of particular interest for organic thermoelectrics. ; Funding Agencies|Swedish Research CouncilSwedish Research Council [2016-03979]; AForsk [18-313, 19310]; Olle Engkvists Stiftelse [204-0256]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Finnish Cultural FoundationFinnish Cultural Foundation; Finnish Foundation for Technology Promotion; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [Dnr KAW 2014.0041]

INTRODUCTION: The COVID-19 outbreak has become the dominant issue throughout the world whilst the governments, nations and health services are trying to deal with its impact. The aim of our study is to assess the impact of COVID-19 on patients treated with radical prostatectomy (RP) for prostate cancer (PCa) at European referral centers in terms of surgical volume (SV), waiting list meant as time from biopsy to surgery (WL) and risk of adverse pathologic findings at RP due to the selection of men with more adverse disease characteristics at final pathology. MATERIAL AND METHODS: Consecutive patients with a diagnosis of histologically proven PCa treated with RP between March 2020 (WHO declaration of pandemic) and December 2020 were identified. Patients with metastatic disease not eligible to local treatment and recurrent prostate cancer after RP or RT were excluded. Patients treated at the same institutions between March 2019 and December 2019 were considered as the control group. Multivariable logistic regression analysis tested the impact of the COVID-19 outbreak on the risk of adverse pathologic findings at RP after adjusting for confounders. The percentage change of SV and WL was assessed comparing the months of pandemic with the equivalent timespan of the previous year. RESULTS: A total of 2,574 patients treated with RP (927 cases and 1647 controls) were identified in 8 European tertiary referral centers. At multivariable analysis patients who were treated during the pandemic had higher risk of extra prostatic disease (OR:1.35, p = 0.038) and lymph node invasion (LNI) (OR:1.72, p = 0.048). An average 23% reduction of the SV with the equivalent timespan of the previous year allowed an illusory reduction of the WL after the peak gained during the first wave of COVID-19. CONCLUSIONS: Our results showed that the COVID-19 outbreak resulted in a delay in the administration of curative-intent therapies in patients with localized PCa. This, in turn, resulted in a stage migration phenomenon with a potential impact on ...

Spintronics holds great potential for next-generation high-speed and low-power consumption information technology. Recently, lead halide perovskites (LHPs), which have gained great success in optoelectronics, also show interesting magnetic properties. However, the spin-related properties in LHPs originate from the spin-orbit coupling of Pb, limiting further development of these materials in spintronics. Here, we demonstrate a new generation of halide perovskites, by alloying magnetic elements into optoelectronic double perovskites, which provide rich chemical and structural diversities to host different magnetic elements. In our iron-alloyed double perovskite, Cs2Ag(Bi:Fe)Br-6, Fe3+ replaces Bi3+ and forms FeBr6 clusters that homogenously distribute throughout the double perovskite crystals. We observe a strong temperature-dependent magnetic response at temperatures below 30 K, which is tentatively attributed to a weak ferromagnetic or antiferromagnetic response from localized regions. We anticipate that this work will stimulate future efforts in exploring this simple yet efficient approach to develop new spintronic materials based on lead-free double perovskites. ; Funding Agencies|Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW 2019.0082]; Swedish Energy AgencySwedish Energy Agency [2018004357, P43288-1]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; Grant Agency of the Czech RepublicGrant Agency of the Czech Republic [GA19-05259S]; China Scholarship Council (CSC)China Scholarship Council; U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering DivisionUnited States Department of Energy (DOE); European CommunityEuropean Community (EC) [312284]; Czech Ministry of EducationMinistry of Education, Youth & Sports - Czech Republic [LM2015057]; CERIC users grant; International Synchrotron Access Program of the Australian Synchrotron