Room-temperature drift mobilities of 4500 square centimeters per volt second for electrons and 3800 holes have been measured in high-purity single-crystal diamond grown using a chemical vapor deposition process. The low-field mobility values were determined by the time-of-flight technique on thick, intrinsic, freestanding plates verified current-voltage measurements p-i junction diodes. improvement electronic properties reproducibility those are encouraging research on, development of,...

Low-toxic bismuth-based perovskites are prepared for the possible replacement of lead perovskite in solar cells. The have a hexagonal crystalline phase and light absorption visible region. A power conversion efficiency over 1% is obtained cell with Cs3 Bi2 I9 perovskite, it concluded that bismuth very promising properties further development

We report on perovskite (CH3NH3)PbI3-sensitized solid-state solar cells using spiro-OMeTAD, poly(3-hexylthiophene-2,5-diyl) (P3HT) and 4-(diethylamino)benzaldehyde diphenylhydrazone (DEH) as hole transport materials (HTMs) with a light to electricity power conversion efficiency of 8.5%, 4.5%, 1.6%, respectively, under AM 1.5G illumination 1000 W/m2 intensity. Photoinduced absorption spectroscopy (PIA) shows that transfer occurs from the (CH3NH3)PbI3 HTMs after excitation (CH3NH3)PbI3. The...

The electronic structure and chemical composition of efficient CH3NH3PbI3 perovskite solar cell materials deposited onto mesoporous TiO2 were studied using photoelectron spectroscopy with hard X-rays. With this technique, it is possible to directly measure the occupied energy levels as well buried beneath thereby determine level matching interface. measurements valence in good agreement simulated density states, investigation gives information on character levels. We also show that two...

A two-step deposition technique is used for preparing CH3NH3PbI3 perovskite solar cells. Using ZrO2 and TiO2 as a mesoporous layer, we obtain an efficiency of 10.8% 9.5%, respectively, under 1000 W m−2 illumination. The based cell shows higher photovoltage longer electron lifetime than the cell.

The past few years, two perovskite materials have attracted much attention in the solar cell community: CH3NH3PbI3 and CH3NH3PbI3–xClx. While these are usually characterized using their structure (via X-ray diffraction (XRD)) performance within communities, not so has been devoted to surface chemical composition and, specifically, composition. Photoelectron spectroscopy (PES) can easily fulfill this task, addition information, PES provides an overall picture of electronic its relation...

Solution-processed organometal trihalide perovskite solar cells are attracting increasing interest, leading to high performances over 15% in thin film architectures. Here, we probe the presence of sub gap states both solid and mesosuperstructured films determine that they strongly influence photoconductivity response splitting quasi-Fermi levels cells. We find while planar superior terms charge carrier mobility (in excess 20 cm(2) V(-1) s(-1)) emissivity, heterojunction limited photovoltage...

We report for the first time use of a perovskite (CH3NH3PbI3) absorber in combination with ZnO nanorod arrays (NRAs) solar cell applications. The material has higher absorption coefficient than molecular dye sensitizers, gives better stability, and is therefore more suited as sensitizer NRAs. A efficiency 5.0% was achieved under 1000 W m−2 AM 1.5 G illumination structure: NRA/CH3NH3PbI3/spiro-MeOTAD/Ag. Moreover, shows good long-term stability. Using transient photocurrent photovoltage...

Mixed ion perovskite solar cells (PSC) are manufactured with a metal‐free hole contact based on press‐transferred single‐walled carbon nanotube (SWCNT) film infiltrated 2,2,7,‐7‐tetrakis(N,N‐di‐p‐methoxyphenylamine)‐9,90‐spirobifluorene (Spiro‐OMeTAD). By means of maximum power point tracking, their stabilities compared those standard PSCs employing spin‐coated Spiro‐OMeTAD and thermally evaporated Au back contact, under full 1 sun illumination, at 60 °C, in N 2 atmosphere. During the 140 h...

Lead-based perovskites show very promising properties for use in solar cells; however, the toxicity of lead is a potential inhibitor large-scale application these cells. Here, low-toxic bismuth halide, CsBi3I10, synthesized from solution and optical crystal structure are compared with previously reported Cs3Bi2I9 perovskite, photovoltaic also investigated. The XRD pattern suggests that CsBi3I10 film has layered different dominating growth direction than perovskite. A band gap 1.77 eV...

Hybrid hole-transporting material and selective contact for perovskite solar cells was manufactured by industrially viable materials methods.

Abstract Solution‐processed colloidal quantum dot (CQD) solar cells harvesting the infrared part of spectrum are especially interesting for future use in semitransparent windows or multilayer cells. To improve device power conversion efficiency (PCE) and stability cells, surface passivation dots is vital research CQD Herein, inorganic CsPbI 3 perovskite (CsPbI ‐P) coating on PbS CQDs with a low‐temperature, solution‐processed approach reported. The cell ‐P gives high PCE 10.5% exhibits...

Abstract Inorganic CsPbI 3 perovskite quantum dot (PQD) receives increasing attention for the application in new generation solar cells, but defects on surface of PQDs significantly affect photovoltaic performance and stability cells. Herein, amino acids are used as dual‐passivation ligands to passivate using a facile single‐step ligand exchange strategy. The PQD properties investigated depth by combining experimental studies theoretical calculation approaches. solid films with thoroughly...

An analysis is provided of MA-free Sn/Pb-perovskite solar cells fabricated using PEDOT:PSS, 2PACz, and Br-2PACz as the HTL. efficiency 19.51% has been reached by with improved device stability, thanks to suppressed recombination.

In many applications, the number of interconnects or weights in a neural network is so large that learning time for conventional backpropagation algorithm can become excessively long. Numerical optimization theory offers rich and robust set techniques which be applied to networks improve rates. particular, conjugate gradient method easily adapted problem. This paper describes method, its application problem presents results numerical tests compare backpropagation, steepest descent methods....

Abstract Two triphenylamine‐based metal‐free organic sensitizers, D35 with a single anchor group and M14 two groups, have been applied in dye‐sensitized solar cells (DSCs) solid hole transporting material or liquid iodide/triiodide based electrolyte. Using the molecular conductor 2,2',7,7'‐tetrakis‐( N , ‐di‐ p ‐methoxyphenyl‐amine)9,9'‐spirobifluorene (spiro‐OMeTAD), good overall conversion efficiencies of 4.5% for 4.4% were obtained under standard AM 1.5G illumination (100 mW cm −2 )....

Three new sensitizers for photoelectrochemical solar cells were synthesized consisting of a triphenylamine donor, rhodanine-3-acetic acid acceptor and polyene connection. The conjugation length was systematically increased, which resulted in two effects: first, it led to red-shift the optical absorption dyes, resulting an improved spectral overlap with spectrum. Secondly, oxidation potential decreased systematically. excited state levels were, however, calculated be nearly stationary....

Cesium and methylammonium bismuth iodides (Cs3Bi2I9 MA3Bi2I9) are new low-toxic air stable compounds in the perovskite solar cell family with promising characteristics. Here, electronic structure nature of their optical transitions, dielectric constant, charge carrier properties assessed for photovoltaic applications density functional theory (DFT) calculations experiments. The calculated direct indirect band gap values Cs3Bi2I9 (2.17 2.0 eV) MA3Bi2I9 1.97 found to be good agreement...

Efficient solid state dye-sensitized solar cells (sDSCs) were obtained using a small hole transport material, MeO-TPD (N,N,N',N'-tetrakis(4-methoxyphenyl)benzidine), after an initial light soaking treatment. It was discovered that the treatment for based is essential in order to achieve high efficiency (4.9%), which outperforms spiro-OMeTAD sDSCs same dye and device preparation parameters. A mechanism on Li(+) ion migration suggested explain effect. observed electron lifetime sDSC strongly...

Abstract Tremendous progress has recently been achieved in the field of perovskite solar cells (PSCs) as evidenced by impressive power conversion efficiencies (PCEs); but high PCEs >20% PSCs so far mostly using hole transport material (HTM) spiro‐OMeTAD; however, relatively low conductivity and cost spiro‐OMeTAD significantly limit its potential use large‐scale applications. In this work, two new organic molecules with spiro[fluorene‐9,9′‐xanthene] (SFX)‐based pendant groups, X26 X36,...

Hard X-ray photoelectron spectroscopy (HAXPES) has been used to study the effects of adding Li-TFSI hole conducting molecular thin films 2,2′,7,7′-tetrakis(N,N′-di-p-methoxyphenylamine)-9,9′-spirobifluorene (spiro-OMeTAD). The work shows that a procedure mixing solution into spiro-OMeTAD solution, and subsequent spin-coating this mixture solid film causes Fermi level move closer HOMO level. Hence, gives similar as p-dopant. Specific from doping on valence levels were also characterized....

Further understanding and optimization of dye solar cells towards stable efficient devices necessitate implementation the characterization techniques.

Abstract Here, a lead‐free silver bismuth iodide (AgI/BiI 3 ) with crystal structure space group R m is investigated for use in solar cells. Devices based on the deposited from solution top of TiO 2 and conducting polymer poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) as hole‐transport layer are prepared photovoltaic performance very promising power conversion efficiency over %, which higher than previously reported bismuth‐halide materials Photocurrent generation observed between 350 700 nm,...