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The electrical and structural behavior of uniformly mixed films of boron subphthalocyanine chloride (SubPc) and C60 and their performance in organic photovoltaic cells is explored. Device performance shows a strong dependence on active‐layer donor–acceptor composition, and peak efficiency is realized at 80 wt.% C60. The origin of this C60‐rich optimum composition is elucidated in terms of morphological changes in the active layer upon diluting SubPc with C60. While neat SubPc is found to be amorphous, mixed films containing 80 wt.% C60 show clear nanocrystalline domains of SubPc. Supporting electrical characterization indicates that this change in morphology coincides with an increase in the hole mobility of the SubPc:C60 mixture, with peak mobility observed at a composition of 80 wt.% C60. Organic photovoltaic cells constructed using this optimum SubPc:C60 ratio realize a power conversion efficiency of (3.7 ± 0.1)% under 100 mW cm−2 simulated AM1.5G solar illumination.

We report as imple and rapid saliva-based SARS-CoV-2 antigen test that utilizes an ewly developed dimeric DNAa ptamer,d enoted as DSA1N5, that specifically recognizes the spike proteins of the wildtype virus and its Alpha and Delta variants with dissociation constants of 120, 290 and 480 pM, respectively,a nd binds pseudotyped lentiviruses expressing the wildtype and alpha trimeric spike proteins with affinity constants of 2.1 pM and 2.3 pM, respectively.T o develop ah ighly sensitive test, DSA1N5 was immobilized onto gold electrodes to produce an electrochemical impedance sensor,which was capable of detecting 1000 viral particles per mL in 1:1d iluted saliva in under 10 min without any further sample processing. Evaluation of 36 positive and 37 negative patient saliva samples produced aclinical sensitivity of 80.5 % and specificity of 100 %a nd the sensor could detect the wildtype virus as well as the Alpha and Delta variants in the patient samples,w hich is the first reported rapid test that can detect any emerging variant of SARS-CoV-2.

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Radiation-induced bystander effect (RIBE) is a poorly understood phenomenon wherein non-targeted cells exhibit effects of radiation. We have reported that cell-free chromatin (cfCh) particles that are released from dying cells can integrate into genomes of surrounding healthy cells to induce DNA damage and inflammation. This raised the possibility that RIBE might be induced by cfCh released from irradiated dying cells. When conditioned media from BrdU-labeled irradiated cells were passed through filters of pore size 0.22 µm and incubated with unexposed cells, BrdU-labeled cfCh particles could be seen to readily enter their nuclei to activate H2AX, active Caspase-3, NFκB, and IL-6. A direct relationship was observed with respect to activation of RIBE biomarkers and radiation dose in the range of 0.1–50 Gy. We confirmed by FISH and cytogenetic analysis that cfCh had stably integrated into chromosomes of bystander cells and had led to extensive chromosomal instability. The above RIBE effects could be abrogated when conditioned media were pre-treated with agents that inactivate cfCh, namely, anti-histone antibody complexed nanoparticles (CNPs), DNase I and a novel DNA degrading agent Resveratrol-copper (R-Cu). Lower hemi-body irradiation with γ-rays (0.1–50 Gy) led to activation of H2AX, active Caspase-3, NFκB, and IL-6 in brain cells in a dose-dependent manner. Activation of these RIBE biomarkers could be abrogated by concurrent treatment with CNPs, DNase I and R-Cu indicating that activation of RIBE was not due to radiation scatter to the brain. RIBE activation was seen even when mini-beam radiation was delivered to the umbilical region of mice wherein radiation scatter to brain was negligible and could be abrogated by cfCh inactivating agents. These results indicate that cfCh released from radiation-induced dying cells are activators of RIBE and that it can be prevented by treatment with appropriate cfCh inactivating agents.

In this work, we report a lead-free hybrid halide perovskite system with a very high piezoelectric charge density for applications in nanogenerators. We use materials engineering by incorporation of formamidinium tin iodide, FASnI 3 , in a soft polymer (polyvinylidene fluoride, PVDF) matrix and demonstrate highperformance large-area flexible piezoelectric nanogenerators. This is achieved by using self-poled thin films of a FASnI 3 :PVDF nanocomposite. The fabricated devices show an output voltage up to ∼23 V and power density of 35.05 mW cm −2 across a 1 MΩ resistor, under a periodic vertical compression, with a release pressure of ∼0.1 MPa. Measured values of the local piezoelectric coefficient (d 33 ) of these films reach up to 73 pm/V. We provide the microscopic mechanism using first-principles calculations, which suggest that a soft elastic nature and soft polar optic phonons are responsible for the high piezoelectric response of FASnI 3 . Our studies open up a route to high-performance nanogenerators using a lead-free organic−inorganic halide perovskite family of materials.

An insight into the analogies, state-of-the-art technologies, concepts, and prospects under the umbrella of perovskite materials (both inorganicorganic hybrid halide perovskites and ferroelectric perovskites) for future multifunctional energy conversion and storage devices is provided. Often, these are considered entirely different branches of research; however, considering them simultaneously and holistically can provide several new opportunities. Recent advancements have highlighted the potential of hybrid perovskites for high-efficiency solar cells. The intrinsic polar properties of these materials, including the potential for ferroelectricity, provide additional possibilities for simultaneously exploiting several energy conversion mechanisms such as the piezoelectric, pyroelectric, and thermoelectric effect and electrical energy storage. The presence of these phenomena can support the performance of perovskite solar cells. The energy conversion using these effects (piezo-, pyro-, and thermoelectric effect) can also be enhanced by a change in the light intensity. Thus, there lies a range of possibilities for tuning the structural, electronic, optical, and magnetic properties of perovskites to simultaneously harvest energy using more than one mechanism to realize an improved efficiency. This requires a basic understanding of concepts, mechanisms, corresponding material properties, and the underlying physics involved with these effects. His current research focuses on developing functional inorganic−organic hybrid materials and energy conversion devices including perovskite solar cells.are found to have lower t-values (0.75 < t < 1.0). t-values help in governing and tuning the presence of ferroelectricity in perovskites [11] and are responsible for the transition temperatures in ferroelectrics. [57] In the case of hybrid inorganic-organic perovskites, the A-site and/or X-site ions are replaced by molecular building blocks; hence, the tolerance