Reliability of Small Molecule Organic Photovoltaics with Electron‐Filtering Compound Buffer Layers

Electron‐filtering compound buffer layers (EF‐CBLs) improve charge extraction in organic photovoltaic cells (OPVs) by blending an electron‐conducting fullerene with a wide energy gap exciton‐blocking molecule. It is found that devices with EF‐CBLs with high glass transition temperatures and a low crystallization rate produce highly stable morphologies and devices. The most stable OPVs employ 1:1 2,2′,2″‐(1,3,5‐benzenetriyl tris‐[1‐phenyl‐1H‐benzimidazole] TPBi:C₇₀ buffers that lose <20% of their initial power conversion efficiency of 6.6 ± 0.6% after 2700 h under continuous simulated AM1.5G illumination, and show no significant degradation after 100 days of outdoor aging. When exposed to 100‐sun (100 kW m^?2) concentrated solar illumination for 5 h, their power conversion efficiencies decrease by <8%. Moreover, it is found that the reliability of the devices employing stable EF‐CBLs has either reduced or no dependence on operating temperature up to 130 °C compared with BPhen:C₆₀ devices whose fill factors show thermally activated degradation. The robustness of TPBi:C₇₀ devices under extreme aging conditions including outdoor exposure, high temperature, and concentrated illumination is promising for the future of OPV as a stable solar cell technology.     

Superwetting Monolithic Hollow‐Carbon‐Nanotubes Aerogels with Hierarchically Nanoporous Structure for Efficient Solar Steam Generation

Solar steam generation has been proven to be one of the most efficient approaches for harvesting solar energy for diverse applications such as distillation, desalination, and production of freshwater. Here, the synthesis of monolithic carbon aerogels by facile carbonization of conjugated microporous polymer nanotubes as efficient solar steam generators is reported. The monolithic carbon‐aerogel networks consist of randomly aggregated hollow‐carbon‐nanotubes (HCNTs) with 100–250 nm in diameter and a length of up to several micrometers to form a hierarchically nanoporous network structure. Treatment of the HCNTs aerogels with an ammonium peroxydisulfate/sulfuric acid solution endows their superhydrophilic wettability which is beneficial for rapid transportation of water molecules. In combination with their abundant porosity (92%) with open channel structure, low apparent density (57 mg cm^?3), high specific surface area (826 m² g^?1), low thermal conductivity (0.192 W m^?1 K^?1), and broad light absorption (99%), an exceptionally high conversion efficiency of 86.8% is achieved under 1 sun irradiation, showing great potential as an efficient photothermal material for solar steam generation. The findings may provide a new opportunity for tailored design and creation of new carbon‐aerogels‐based photothermal materials with adjustable structure, tunable porosity, simple fabrication process, and high solar energy conversion efficiency for solar steam generation.     

Enhanced Efficiency of Hot‐Cast Large‐Area Planar Perovskite Solar Cells/Modules Having Controlled Chloride Incorporation

Organic–inorganic perovskite photovoltaics are an emerging solar technology. Developing materials and processing techniques that can be implemented in large‐scale manufacturing is extremely important for realizing the potential of commercialization. Here we report a hot‐casting process with controlled Cl^? incorporation which enables high stability and high power‐conversion‐efficiencies (PCEs) of 18.2% for small area (0.09 cm²) and 15.4% for large‐area (≈1 cm²) single solar cells. The enhanced performance versus tri‐iodide perovskites can be ascribed to longer carrier diffusion lengths, improved uniformity of the perovskite film morphology, favorable perovskite crystallite orientation, a halide concentration gradient in the perovskite film, and reduced recombination by introducing Cl^?. Additionally, Cl^? improves the device stability by passivating the reaction between I^? and the silver electrode. High‐quality thin films deployed over a large‐area 5 cm × 5 cm eight‐cell module have been fabricated and exhibit an active‐area PCE of 12.0%. The feasibility of material and processing strategies in industrial large‐scale coating techniques is then shown by demonstrating a “dip‐coating” process which shows promise for large throughput production of perovskite solar modules.     

Continuous 3D Titanium Nitride Nanoshell Structure for Solar‐Driven Unbiased Biocatalytic CO2 Reduction

Z‐scheme‐inspired tandem photoelectrochemical (PEC) cells have received attention as a sustainable platform for solar‐driven CO₂ reduction. Here, continuously 3D‐structured, electrically conductive titanium nitride nanoshells (3D TiN) for biocatalytic CO₂‐to‐formate conversion in a bias‐free tandem PEC system are reported. The 3D TiN exhibits a periodically porous network with high porosity (92.1%) and conductivity (6.72 × 10⁴ S m^?1), which allows for high enzyme loading and direct electron transfer (DET) to the immobilized enzyme. It is found that the W‐containing formate dehydrogenase from Clostridium ljungdahlii (ClFDH) on the 3D TiN nanoshell is electrically activated through DET for CO₂ reduction. At a low overpotential of 40 mV, the 3D TiN‐ClFDH stably converts CO₂ to formate at a rate of 0.34 µmol h^?1 cm^?2 and a faradaic efficiency (FE) of 93.5%. Compared to a flat TiN‐ClFDH, the 3D TiN‐ClFDH shows a 58 times higher formate production rate (1.74 µmol h^?1 cm^?2) at 240 mV of overpotential. Lastly, a bias‐free biocatalytic tandem PEC cell that converted CO₂ to formate at an average rate of 0.78 µmol h^?1 and an FE of 77.3% only using solar energy and water is successfully assembled.     

Cobalt Polypyridyl Complexes as Transparent Solution‐Processable Solid‐State Charge Transport Materials

Charge transport materials (CTMs) are traditionally inorganic semiconductors or metals. However, over the past few decades, new classes of solution‐processable CTMs have evolved alongside new concepts for fabricating electronic devices at low cost and with exceptional properties. The vast majority of these novel materials are organic compounds and the use of transition metal complexes in electronic applications remains largely unexplored. Here, a solution‐processable solid‐state charge transport material composed of a blend of [Co(bpyPY4)](OTf)₂ and Co(bpyPY4)](OTf)₃ where bpyPY4 is the hexadentate ligand 6,6′‐bis(1,1‐di(pyridin‐2‐yl)ethyl)‐2,2′‐bipyridine and OTf^? is the trifluoromethanesulfonate anion is reported. Surprisingly, these films exhibit a negative temperature coefficient of conductivity (dσ/dT) and non‐Arrhenius behavior, with respectable solid‐state conductivities of 3.0 S m^?1 at room temperature and 7.4 S m^?1 at 4.5 K. When employed as a CTM in a solid‐state dye‐sensitized solar cell, these largely amorphous, transparent films afford impressive solar energy conversion efficiencies of up to 5.7%. Organic–inorganic hybrid materials with negative temperature coefficients of conductivity generally feature extended flat π‐systems with strong π–π interactions or high crystallinity. The lack of these features promotes [Co(bpyPY4)](OTf)_{2+ x} films as a new class of CTMs with a unique charge transport mechanism that remains to be explored.     

Four‐Terminal Perovskite/Silicon Multijunction Solar Modules

Multijunction solar cells employing perovskite and crystalline‐silicon (c‐Si) light absorbers bear the exciting potential to surpass the efficiency limit of market‐leading single‐junction c‐Si solar cells. However, scaling up this technology and maintaining high efficiency over large areas are challenging as evidenced by the small‐area perovskite/c‐Si multijunction solar cells reported so far. In this work, a scalable four‐terminal multijunction solar module design employing a 4 cm² semitransparent methylammonium lead triiodide perovskite solar module stacked on top of an interdigitated back contact c‐Si solar cell of identical area is demonstrated. With a combination of optimized transparent electrodes and efficient module design, the perovskite/c‐Si multijunction solar modules exhibit power conversion efficiencies of 22.6% on 0.13 cm² and 20.2% on 4 cm² aperture area. Furthermore, a detailed optoelectronic loss analysis along with strategies to enhance the performance is discussed.     

Ni‐Rich/Co‐Poor Layered Cathode for Automotive Li‐Ion Batteries: Promises and Challenges

To pursue a higher energy density (>300 Wh kg^?1 at the cell level) and a lower cost (<$125 kWh^?1 expected at 2022) of Li‐ion batteries for making electric vehicles (EVs) long range and cost‐competitive with internal combustion engine vehicles, developing Ni‐rich/Co‐poor layered cathode (LiNi_1?x?yCo_xMn_yO₂, x+y ≤ 0.2) is currently one of the most promising strategies because high Ni content is beneficial to high capacity (>200 mAh g^?1) while low Co content is favorable to minimize battery cost. Unfortunately, Ni‐rich cathodes suffer from limited structure stability and electrode/electrolyte interface stability in the charged state, leading to electrode degradation and poor cycling performance. To address these problems, various strategies have been employed such as doping, structural optimization design (e.g., core–shell structure, concentration‐gradient structure, etc.), and surface coating. In this review, five key aspects of Ni‐rich/Co‐poor layered cathode materials are explored: energy density, fast charge capability, service life including cycling life and calendar life, cost and element resources, and safety. This enables a comprehensive analysis of current research advances and challenges from the perspective of both academy and industry to help facilitate practical applications for EVs in the future.     

Biomimetic MXene Textures with Enhanced Light‐to‐Heat Conversion for Solar Steam Generation and Wearable Thermal Management

2D materials are of particular interest in light‐to‐heat conversion, yet challenges remain in developing a facile method to suppress their light reflection. Herein, inspired by the black scales of Bitis rhinoceros, a generalized approach via sequential thermal actuations to construct biomimetic 2D‐material nanocoatings, including Ti₃C₂T_x MXene, reduced graphene oxide (rGO), and molybdenum disulfide (MoS₂) is designed. The hierarchical MXene nanocoatings result in broadband light absorption (up to 93.2%), theoretically validated by optical modeling and simulations, and realize improved light‐to‐heat performance (equilibrium temperature of 65.4 °C under one‐sun illumination). With efficient light‐to‐heat conversion, the bioinspired MXene nanocoatings are next incorporated into solar steam‐generation devices and stretchable solar/electric dual‐heaters. The MXene steam‐generation devices require much lower solar‐thermal material loading (0.32 mg cm^?2) and still guarantee high steam‐generation performance (1.33 kg m^?2 h^?1) compared with other state‐of‐the‐art devices. Additionally, the mechanically deformed MXene structures enable the fabrication of stretchable and wearable heaters dual‐powered by sunlight and electricity, which are reversibly stretched and heated above 100 °C. This simple fabrication process with effective utilization of active materials promises its practical application value for multiple solar–thermal technologies.     

Nitrile‐Substituted QA Derivatives: New Acceptor Materials for Solution‐Processable Organic Bulk Heterojunction Solar Cells

The development of non‐fullerene‐based electron acceptors (especially organic molecules with sufficient absorption property within the solar spectrum region) for bulk‐heterojunction (BHJ) organic solar cells (OSCs) is an important issue for the achievement of high photoconversion efficiency. In this contribution, a new class of organic acceptors di‐cyan substituted quinacridone derivatives (DCN‐nCQA, n = 4, 6 and 8) for BHJ solar cells was designed and synthesized. DCN‐nCQA molecules possess facile synthesis, solution processability, visible and near‐IR light absorption and relatively stable characteristics. The DCN‐8CQA molecule exhibited a proper LUMO energy level (–4.1 eV), small bandgap (1.8 eV) and moderate electron mobility (10^?4 cm² V^?1 S^?1), suggesting that this molecule is an ideal acceptor material for the classical donor material regio‐regular poly (3‐hexylthiophene) (P3HT). A photovoltaic device with a structure of [ITO/PEDOT:PSS/P3HT:DCN‐8CQA/LiF/Al] displayed a power conversion efficiency of 1.57% and a fill factor of 57% under 100 mW cm^?2 AM 1.5G simulated solar illumination. The DCN‐nCQA molecules showed remarkable absorption in the region from 650 to 700 nm, where P3HT has a weak absorption promoting overlap with the solar spectrum and potentially improving the performance of the solar cell.     

The Role of Antireflective Coating CYTOP,Immersion Oil,and Sensitizer Selection in Fabricating a 2.3 V, 10% Power Conversion Efficiency SSM‐DSC Device

Sequential series multijunction dye‐sensitized solar cells (SSM‐DSCs) can power solar‐to‐fuel processes with a single illuminated area device. Dye selection and strategies limiting photon losses are critical in SSM‐DSC devices for higher performance systems. Herein, an efficient and readily applicable spin coating protocol on glass surfaces with an antireflective fluoropolymer (CYTOP) is applied to an SSM‐DSC architecture. Combining CYTOP with the use of an immersion oil between glass spacers in a three subcell SSM‐DSC with judiciously selected TiO₂ photoanode sensitizers and thicknesses, an overall power conversion efficiency (PCE) of 10.1% is obtained with an output of 2.3 V. Without external bias, this SSM‐DSC configuration shows an impressive overall solar‐to‐fuel conversion efficiency of 6% when powering IrO₂ and Au₂O₃ electrocatalysts for CO₂ and H₂O to CO and H₂ conversion in aqueous solution. The role of CYTOP, immersion oil, sensitizer selection, and film thickness on SSM‐DSC devices is discussed along with the stability of this system.     

Negligible‐Pb‐Waste and Upscalable Perovskite Deposition Technology for High‐Operational‐Stability Perovskite Solar Modules

An upscalable perovskite film deposition method combining raster ultrasonic spray coating and chemical vapor deposition is reported. This method overcomes the coating size limitation of the existing stationary spray, single‐pass spray, and spin‐coating methods. In contrast with the spin‐coating method (>90% Pb waste), negligible Pb waste during PbI₂ deposition makes this method more environmentally friendly. Outstanding film uniformity across the entire area of 5 cm × 5 cm is confirmed by both large‐area compatible characterization methods (electroluminescence and scattered light imaging) and local characterization methods (atomic force microscopy, scanning electron microscopy, photoluminescence mapping, UV–vis, and X‐ray diffraction measurements on multiple sample locations), resulting in low solar cell performance decrease upon increasing device area. With the FAPb(I_0.85Br_0.15)₃ (FA = formamidinium) perovskite layer deposited by this method, champion solar modules show a power conversion efficiency of 14.7% on an active area of 12.0 cm² and an outstanding shelf stability (only 3.6% relative power conversion efficiency decay after 3600 h aging). Under continuous operation (1 sun light illumination, maximum power point condition, dry N₂ atmosphere with <5% relative humidity, no encapsulation), the devices show high light‐soaking stability corresponding to an average T₈₀ lifetime of 535 h on the small‐area solar cells and 388 h on the solar module.     

THE PERFORMANCE OF SPRAY‐IRRIGATED ULVA LACTUCA (ULVOPHYCEAE,CHLOROPHYTA) AS A CROP AND AS A BIOFILTER OF FISHPOND EFFLUENTS1

The seaweed Ulva lactuca L. was spray cultured by mariculture effluents in a mattress‐like layer, held in air on slanted boards by plastic netting. Air‐agitated seaweed suspension tanks were the reference. Growth rate, yield, and ammonia‐N removal rate were 11.8% · d^?1, 171 g fresh weight (fwt) · m^?2 · d^?1, and 5 g N · m^?2 · d^?1, respectively, by the spray‐cultured U. lactuca, and 16.9% · d^?1, 283 g fwt · m^?2 · d^?1, and 7 g N · m^?2 · d^?1, respectively, by the tank U. lactuca. Biomass protein content was similar in both treatments. Dissolved oxygen in the fishpond effluent water was raised by >3 mg · L^?1 and pH by up to half a unit, upon passage through both culture systems. The data suggest that spray‐irrigation culture of U. lactuca in this simple green‐mattress‐like system supplies the seaweed all it needs to grow and biofilter at rates close to those in standard air‐agitated tank culture.     

A Low‐Temperature Thin‐Film Encapsulation for Enhanced Stability of a Highly Efficient Perovskite Solar Cell

The stability of a perovskite solar cell (PSC) is enhanced significantly by applying a customized thin‐film encapsulation (TFE). The TFE is composed of a multilayer stack of organic/inorganic layers deposited by initiated chemical vapor deposition and atomic layer deposition, respectively, whose water vapor transmission rate is on the order of 10^?4 g m^?2 d^?1 at an accelerated condition of 38 °C and 90% relative humidity (RH). The TFE is optimized, taking into consideration various aspects of thermosensitive PSCs. Lowering the process temperature is one of the most effective methods for minimizing the thermal damage to the PSC during the monolithic integration of the TFE onto PSC. The direct deposition of TFE onto a PSC causes less than 0.3% degradation (from 18.5% to 18.2%) in the power conversion efficiency, while the long‐term stability is substantially improved; the PSC retains 97% of its original efficiency after a 300 h exposure to an accelerated condition of 50 °C and 50% RH, confirming the enhanced stability of the PSC against moisture. This is the first demonstration of a TFE applied directly onto PSCs in a damage‐free manner, which will be a powerful tool for the development of highly stable PSCs with high efficiency.     

A Portable and Efficient Solar‐Rechargeable Battery with Ultrafast Photo‐Charge/Discharge Rate

The solar‐rechargeable electric energy storage systems (SEESSs), which can simultaneously harvest and store solar energy, are considered a promising next‐generation renewable energy supply system. However, the difficulty in meeting the demands of higher overall photoelectric conversion and storage efficiency (PCSE) with both high power density and large energy density in the current SEESSs severely limit their practical application. Herein, a new class is demonstrated of portable and highly efficient SEESS that uniquely integrates a perovskite solar module (PSM) and an aluminum‐ion battery (AIB) directly on a bifunctional aluminum electrode without any external circuit. Such nanostructural design in the SEESS not only exhibits fast photo‐charge/discharge rate (less than one minute) with high power density (above 5000 W kg^?1), but also delivers a high energy density (above 43 Wh kg^?1). By rationally matching the maximum power point voltage of PSM with AIB charging voltage, an excellent solar‐charging efficiency of 15.2% and a high PCSE of 12.04% are achieved, which is among the best in all reported portable SEESSs. Moreover, enhanced PCSE is observed as the light intensity decreases, which makes such SEESS immune from the geographical location and climate limitations for diverse practical applications.     

Highly Passivated n‐Type Colloidal Quantum Dots for Solution‐Processed Thermoelectric Generators with Large Output Voltage

Colloidal quantum dots (CQDs) are attractive materials for thermoelectric applications due to their simple and low‐cost processing; advantageously, they also offer low thermal conductivity and high Seebeck coefficient. To date, the majority of CQD thermoelectric films reported upon have been p‐type, while only a few reports are available on n‐type films. High‐performing n‐ and p‐type films are essential for thermoelectric generators (TEGs) with large output voltage and power. Here, high‐thermoelectric‐performance n‐type CQD films are reported and showcased in high‐performance all‐CQD TEGs. By engineering the electronic coupling in the films, a thorough removal of insulating ligands is achieved and this is combined with excellent surface trap passivation. This enables a high thermoelectric power factor of 24 µW m^?1 K^?2, superior to previously reported n‐type lead chalcogenide CQD films operating near room temperature (<1 µW m^?1 K^?2). As a result, an all‐CQD film TEG with a large output voltage of 0.25 V and a power density of 0.63 W m^?2 at ?T = 50 K is demonstrated, which represents an over fourfold enhancement to previously reported p‐type only CQD TEGs.     

High‐Performance Solar Steam Device with Layered Channels: Artificial Tree with a Reversed Design

Solar steam generation, combining the most abundant resources of solar energy and unpurified water, has been regarded as one of the most promising techniques for water purification. Here, an artificial tree with a reverse‐tree design is demonstrated as a cost‐effective, scalable yet highly efficient steam‐generation device. The reverse‐tree design implies that the wood is placed on the water with the tree‐growth direction parallel to the water surface; accordingly, water is transported in a direction perpendicular to what occurs in natural tree. The artificial tree is fabricated by cutting the natural tree along the longitudinal direction followed by surface carbonization (called as C‐L‐Wood). The nature‐made 3D interconnected micro‐/nanochannels enable efficient water transpiration, while the layered channels block the heat effectively. A much lower thermal conductivity (0.11 W m^?1 K^?1) thus can be achieved, only 1/3 of that of the horizontally cut wood. Meanwhile, the carbonized surface can absorb almost all the incident light. The simultaneous optimizations of water transpiration, thermal management, and light absorption results in a high efficiency of 89% at 10 kW m^?2, among the highest values in literature. Such wood‐based high‐performance, cost‐effective, scalable steam‐generation device can provide an attractive solution to the pressing global clean water shortage problem.     

Flexible Thermoelectric Generators Composed of n‐and p‐Type Silicon Nanowires Fabricated by Top‐Down Method

This study demonstrates the fabrication and characterization of a flexible thermoelectric (TE) power generator composed of silicon nanowires (SiNWs) fabricated by top‐down method and discusses its strain‐dependence analysis. The Seebeck coefficients of the p‐ and n‐type SiNWs used to form a pn‐module are 156.4 and ?146.1 µV K^?1, respectively. The maximum power factors of the p‐ and n‐type SiNWs are obtained as 8.79 and 8.87 mW (m K²)^?1, respectively, under a convex bending of 1.11%, respectively; these are the largest values among the power factors hitherto reported for SiNWs. The dimensionless figure of merit (ZT ) values of the SiNWs at room temperature are 6.8 × 10^?2 and 6.7 × 10^?2 for the convex bent p‐ and n‐type SiNWs, respectively, with a strain of 1.11%. The thermoelectric properties of the pn‐module and its component SiNWs are characterized under strain conditions ranging from ?1.11% to 1.11%. The maximum Seebeck coefficient and power factor of the pn‐module are obtained as 448 µV K^?1 and 14.2 mW (m K²)^?1, respectively, under convex bending of 1.11%. Moreover, the mechanical stability of the TE characteristics of the pn‐module is demonstrated through a continuous bending test of 3000 cycles under convex bending of 0.66%.     

Inhibition of photosynthesis by solar radiation in Dunaliella salina: relative efficiencies of UV-B, UV-A and PAR

Inhibition of photosynthesis after exposure to solar radiation was investigated in the marine green alga Dunaliella salina by monitoring photosynthetic optimal quantum yield F_v/F_m and efficiency of oxygen production. Samples were exposed to solar radiation in Ancient Korinth, Greece (37°58′ N, 23°0′ E) in August 1994. Within 30 min, F_v/F_m and efficiency of oxygen production decreased with similar kinetics with increasing exposure time. The inhibition, however, diminished when ultraviolet radiation was progressively excluded by means of colour filter glasses. Samples exposed for 3 h showed complete or partial recovery of photosynthesis, with almost the same rate under all irradition conditions. The fit of the experimental data with an analytical model describing inhibition of photosynthesis as a function of a linear combination of the photon fluence in the UV-B, UV-A and PAR allows one to estimate the relative mean effectiveness for inhibition by the three spectral ranges [about 2 × 10^?4, 4 × 10^?6 and 2 × 10^?7 (μmol photons m^?2)^?1 for UV-B, UV-A and PAR, respectively].     

A Hybridized Power Panel to Simultaneously Generate Electricity from Sunlight,Raindrops, and Wind around the Clock

With the solar panels quickly spreading across the rooftops worldwide, solar power is now very popular. However, the output of the solar cell panels is highly dependent on weather conditions, making it rather unstable. Here, a hybridized power panel that can simultaneously generate power from sunlight, raindrop, and wind is proposed and demonstrated, when any or all of them are available in ambient environment. Without compromising the output performance and conversion efficiency of the solar cell itself, the presented hybrid cell can deliver an average output of 86 mW m^?2 from the water drops at a dripping rate of 13.6 mL s^?1, and an average output of 8 mW m^?2 from wind at a speed of 2.7 m s^?1, which is an innovative energy compensation to the common solar cells, especially in rainy seasons or at night. Given the compelling features, such as cost‐effectiveness and a greatly expanded working time, the reported hybrid cell renders an innovative way to realize multiple kinds of energy harvesting and as an useful compensation to the currently widely used solar cells. The demonstrated concept here will possibly be adopted in a variety of circumstances and change the traditional way of solar energy harvesting.     

Molecular Engineering Using an Anthanthrone Dye for Low‐Cost Hole Transport Materials: A Strategy for Dopant‐Free,High‐Efficiency,and Stable Perovskite Solar Cells

In this report, highly efficient and humidity‐resistant perovskite solar cells (PSCs) using two new small molecule hole transporting materials (HTM) made from a cost‐effective precursor anthanthrone (ANT) dye, namely, 4,10‐bis(1,2‐dihydroacenaphthylen‐5‐yl)‐6,12‐bis(octyloxy)‐6,12‐dihydronaphtho[7,8,1,2,3‐nopqr]tetraphene (ACE‐ANT‐ACE) and 4,4′‐(6,12‐bis(octyloxy)‐6,12‐dihydronaphtho[7,8,1,2,3‐nopqr]tetraphene‐4,10‐diyl)bis(N,N‐bis(4‐methoxyphenyl)aniline) (TPA‐ANT‐TPA) are presented. The newly developed HTMs are systematically compared with the conventional 2,2′,7,7′‐tetrakis(N,N′‐di‐p‐methoxyphenylamino)‐9,9′‐spirbiuorene (Spiro‐OMeTAD). ACE‐ANT‐ACE and TPA‐ANT‐TPA are used as a dopant‐free HTM in mesoscopic TiO₂/CH₃NH₃PbI₃/HTM solid‐state PSCs, and the performance as well as stability are compared with Spiro‐OMeTAD‐based PSCs. After extensive optimization of the metal oxide scaffold and device processing conditions, dopant‐free novel TPA‐ANT‐TPA HTM‐based PSC devices achieve a maximum power conversion efficiency (PCE) of 17.5% with negligible hysteresis. An impressive current of 21 mA cm^?2 is also confirmed from photocurrent density with a higher fill factor of 0.79. The obtained PCE of 17.5% utilizing TPA‐ANT‐TPA is higher performance than the devices prepared using doped Spiro‐OMeTAD (16.8%) as hole transport layer at 1 sun condition. It is found that doping of LiTFSI salt increases hygroscopic characteristics in Spiro‐OMeTAD; this leads to the fast degradation of solar cells. While, solar cells prepared using undoped TPA‐ANT‐TPA show dewetting and improved stability. Additionally, the new HTMs form a fully homogeneous and completely covering thin film on the surface of the active light absorbing perovskite layers that acts as a protective coating for underlying perovskite films. This breakthrough paves the way for development of new inexpensive, more stable, and highly efficient ANT core based lower cost HTMs for cost‐effective, conventional, and printable PSCs.