Energy Barrier Research Articles

Catalytic Refining Lignin-derived Monomers: Seesaw Effect between Nanoparticle and Single-Atom Pt.

Pt automatically adsorbed on oxygen vacancy of TiO2 via an in-situ interfacial redox reaction, resulting in atomically dispersion of Pt on TiO2.In the upgrading of lignin-derived 4-propylguaiacol, single-atom catalyst (SAC) Pt/TiO2-H achieved a conversion of 96.9% and a demethoxylation selectivity of 93.3% under 3 MPa H2 at 250 °C for 3 h, markedly different from the performance of nanoparticle counterpart that gave deep deoxygenation selectivity over 99.0%. The high demethoxylation activity of SAC Pt/TiO2-H is mainly attributed to its weak hydrogen spillover capacity that suppressed the benzene ring hydrogenation and the deep deoxygenation. Additionally, SAC Pt/TiO2-H reduced the energy barrier of CAr-OCH3 bond cleavage and accordingly lowered the Gibbs free energy of the demethoxylation reaction. This facile method could fabricate single-atom Au, Pd, Ir, and Ru supported on TiO2-H, demonstrating the generality of this strategy for the establishment of a library of SACs. Moreover, SAC exhibited versatile capacity in demethoxylation of different lignin-derived monomers and high stability.This study showcases the superiority of atomically dispersed metal catalysts for selective demethoxylation reactions and proposes a renewable alternative to fossil-based 4-alkylphenols through upgrading of lignin-derived monomers.

Main Group SnN4O Single Sites with Optimized Charge Distribution for Boosting the Oxygen Reduction Reaction.

Transition metal single-atom catalysts (SACs) have been regarded as possible alternatives to platinum-based materials due to their satisfactory performance of the oxygen reduction reaction (ORR). By contrast, main-group metal elements are rarely studied due to their unfavorable surface and electronic states. Herein, a main-group Sn-based SAC with penta-coordinated and asymmetric first-shell ligands is reported as an efficient and robust ORR catalyst. The introduction of the vertical oxygen atom breaks the symmetric charge balance, modulating the binding strength to oxygen intermediates and decreasing the energy barrier for the ORR process. As expected, the prepared Sn SAC exhibits outstanding ORR activity with a high half-wave potential of 0.912 V (vs RHE) and an excellent mass activity of 13.1 A mgSn-1 at 0.850 V (vs RHE), which surpasses that of commercial Pt/C and most reported transition-metal-based SACs. Additionally, the reported Sn SAC shows excellent ORR stability due to the strong interaction between Sn sites and the carbon support with oxygen atom as the bridge. The excellent ORR performance of Sn SAC was also proven by both liquid- and solid-state zinc-air battery (ZAB) measurements, indicating its great potential in practical applications.

Low-Coordinated Conductive ZnCu Metal-Organic Frameworks for Highly Selective H2O2 Electrosynthesis.

Direct electrosynthesis of hydrogen peroxide (H2O2) with high production rate and high selectivity through the two-electron oxygen reduction reaction (2e-ORR) offers a sustainable alternative to the energy-intensive anthraquinone technology but remains a challenge. Herein, a low-coordinated, 2Dconductive Zn/Cu metal-organic framework supported on hollow nanocube structures (ZnCu-MOF (H)) is rationally designed and synthesized. The as-prepared ZnCu-MOF (H) catalyst exhibits substantially boosted electrocatalytic kinetics, enhanced H2O2 selectivity, and ultra-high Faradaic efficiency for 2e-ORR process in both alkaline and neutral conditions. Electrochemical measurements, operando/quasi in situ spectroscopy, and theoretical calculation demonstrate that the introduction of Cu atoms with low-coordinated structures induces the transformation of active sites, resulting in the beneficial electron transfer and the optimized energy barrier, thereby improving the electrocatalytic activity and selectivity.

Cu1-Fe Dual Sites for Superior Neutral Ammonia Electrosynthesis from Nitrate.

The electrochemical nitrate reduction reaction (NO3RR) is able to convert nitrate (NO3-) into reusable ammonia (NH3), offering a green treatment and resource utilization strategy of nitrate wastewater and ammonia synthesis. The conversion of NO3- to NH3 undergoes water dissociation to generate active hydrogen atoms and nitrogen-containing intermediates hydrogenation tandemly. The two relay processes compete for the same active sites, especially under pH-neutral condition, resulting in the suboptimal efficiency and selectivity in the electrosynthesis of NH3 from NO3-. Herein, we constructed a Cu1-Fe dual-site catalyst by anchoring Cu single atoms on amorphous iron oxide shell of nanoscale zero-valent iron (nZVI) for the electrochemical NO3RR, achieving an impressive NO3- removal efficiency of 94.8% and NH3 selectivity of 99.2% under neutral pH and nitrate concentration of 50 mg L-1 NO3--N conditions, greatly surpassing the performance of nZVI counterpart. This superior performance can be attributed to the synergistic effect of enhanced NO3- adsorption on Fe sites and strengthened water activation on single-atom Cu sites, decreasing the energy barrier for the rate-determining step of *NO-to-*NOH. This work develops a novel strategy of fabricating dual-site catalysts to enhance the electrosynthesis of NH3 from NO3-, and presents an environmentally sustainable approach for neutral nitrate wastewater treatment.

Fast Water Desalination with a Graphene-MoS2 Nanoporous Heterostructure.

Energy-efficient water desalination is the key to tackle the challenges with drought and water scarcity that affect 1.2 billion people. The material and type of membrane in reverse osmosis water desalination are the key factors in their efficiency. In this work, we explored the potential of a graphene-MoS2 heterostructure membrane for water desalination, focusing on bilayer membranes and their advantages over monolayer counterparts. Through extensive molecular dynamics simulation and statistical analysis, the bilayer MoS2-graphene was investigated and compared to the monolayer of graphene and MoS2. By optimizing the heterostructure membrane, improved water flux was achieved while maintaining a high ion rejection rate. Furthermore, the study delves into the physical mechanisms underlying the superior performance of heterostructure nanopores, comparing them with circular bilayer and monolayer pores. Factors investigated include water structure, hydration shell near the membrane surface, water density, energy barrier using the potential of mean force, and porosity within the nanopore. Our findings contribute to the understanding of heterostructure membranes and their potential in enhancing the water desalination efficiency, providing valuable insights for future membrane design and optimization.

Theoretical Insights into Enhancing Catalytic Performance of Al-Cu Alloy for CO2 Electroreduction toward Ethene Production.

The understanding of the reaction mechanism of CO2 electroreduction (CO2RR) is essential for the precise design of catalysts for specific products with high selectivity. In this work, combined with the computational hydrogen electrode model and kinetic energy barrier calculations, CO2RR pathways on Cu(100) and Al1Cu3(100) are intensively investigated. The free energy barrier of the rate-determining step of ethylene formation is reduced from 1.08 eV for *CCOH formation on Cu(100) to 0.51 eV for *CH2OCHOH formation on Al1Cu3(100) and enhances the catalytic activity. The reaction free energy of *CO-*CO coupling is remarkably reduced from 0.86 eV on Cu(100) to -0.43 eV on Al1Cu3(100) and the coupling barrier is reduced from 0.97 to 0.37 eV, suppressing the production of gas phase CO and enhancing the production of C2 products. Furthermore, the selectivity toward C-O breaking of *CH2CHOH on Cu(100) and *CH2CH2OH on Al1Cu3(100) ensures high selectivity toward ethene rather than ethanol.

DFT Calculations Rationalize Unconventional Regioselectivity in PdII-Catalyzed Defluorinative Alkylation of gem-Difluorocyclopropanes with Hydrazones.

Density functional theory (DFT) calculations have been conducted to gain insight into the unique formation of the branched alkylation product in the PdII-catalyzed defluorinative alkylation of gem-difluorocyclopropanes with hydrazones. The reaction is established to occur in sequence through oxidative addition, β-F elimination, η1-η3 isomerization, transmetalation, η3-η1 isomerization, 3,3'-reductive elimination, deprotonation/N2 extrusion, and proton abstraction. The rate-determining step of the reaction is identified as the β-F elimination, featuring an energy barrier of 28.6 kcal/mol. The 3,3'-reductive elimination transition states are the regioselectivity-determining transition states. The favorable noncovalent π-π interaction between the naphthyl group of gem-difluorocyclopropane and the phenyl group of hydrazone is found to be mainly responsible for the observed regioselectivity.

Electrocatalysts with Highly Dispersed Cerium in Nickel Matrix for Hydrogen Evolution in Alkaline Electrolyte

AbstractIt is challenging to develop highly active and durable electrocatalysts for hydrogen evolution reaction (HER) in alkaline water electrolysis. Herein, an electrocatalyst is synthesized with highly dispersed cerium in a nickel matrix, showing an overpotential of 169 mV for HER at a current density of 500 mA cm−2, about 137 mV lower than that observed without cerium. Kinetic analysis results suggest that doping cerium facilitates the evolution of intermediate H for HER, thus accelerating the process of water dissociation. Density functional theory (DFT) calculations also indicate that the introduction of highly dispersed cerium can lower the energy barrier of the kinetically sluggish Volmer step by altering the orbital occupation near the Fermi level, promoting the process of water dissociation. Furthermore, the electrolyzer constructed with the electrocatalyst exhibits a cell voltage as low as 1.67 V at 800 mA cm−2 for 2000 h in 7 м KOH at 80 °C. The robust property makes it an excellent candidate electrocatalyst for practical applications.

Heterojunction engineering via in-situ electrochemical reconstruction for boosting electrocatalytic biomass upgrading-coupled hydrogen production

Rationally designing and constructing high-performance electrocatalysts is critical for environmental and sustainable electrocatalytic biomass upgrading coupled with hydrogen evolution. Herein, we developed a novel in-situ electrochemical reconstruction strategy to fabricate heterostructured electrocatalysts for efficient biomass upgrading-coupled hydrogen production. Through in-situ anodic and cathodic electrochemical reconstructions, Ni(OH)2-CuO nanorods assembled by nanosheets with abundant low-crystalline Ni(OH)2/crystalline CuO heterojunctions on Cu foam (Ni(OH)2-CuO/CF) and S-doped Ni(OH)2-Cu2O nanofoam formed by cross-linked nanoparticles on CF (Ni(OH)2-Cu2O(S)/CF) were respectively constructed for electrocatalytic 5-hydroxymethylfurfural oxidation reaction (HMFOR) and hydrogen evolution reaction (HER). For the Ni(OH)2-CuO/CF, the overall configuration of nanorods assembled by self-standing nanosheets ensures good conductivity, full exposure of active sites, and fast mass/electron transfer. The abundant Ni(OH)2/CuO heterojunctions provide dual active sites of Ni and Cu to simultaneously adsorb and activate hydroxyl and aldehyde groups in HMF. The electronic interaction between Ni(OH)2 and CuO accelerates the reversible conversion of Ni2+↔Ni3+ to generate more Ni3+ active species and enhances the intrinsic activity of dual active sites to reduce the reaction energy barrier of the rate-determining step. As a result, the Ni(OH)2-CuO/CF shows superior HMFOR performance, with a HMF conversion of 99.3%, a FDCA yield of 98.1%, and stability for 50 cycles in 10 mM HMF+1.0 M KOH medium. Meanwhile, the Ni(OH)2-Cu2O(S)/CF also exhibits remarkable HER activity with an overpotential of only 64.7 mV at 10 mA cm−2 in 1.0 M KOH solution due to its unique structure and composition. When coupling a two-electrode system, the HMFOR-HER system achieves a current density of 10 mA cm−2 at 1.44 V, 221 mV lower than that of the OER-HER system. This work provides an in-situ electrochemical reconstruction strategy for designing advanced heterojunction-rich electrocatalysts for various electrocatalytic applications.

Phosphorus Defect Mediated Electron Redistribution to Boost Anion Exchange Membrane‐Based Alkaline Seawater Electrolysis

AbstractIt is of essential importance to design bifunctional electrocatalysts with excellent performance for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in seawater splitting. Herein, an approach for manipulating electron redistribution in NiCoP treated by P defect (Pv) engineering (NiCoPv@NF) is presented, exhibiting excellent catalytic activities and stability toward HER/OER in alkaline seawater solution. The Pv reduces the surface electrooxidation reconfiguration energy barrier, making it easier to drive the local conversion of crystals to active oxy(hydroxide) in OER. In addition, the Ni site of NiCoPv and the Co site of NiCoOOH are the active sites for HER and OER processes, respectively. In situ generated PO43− adsorbed on the catalyst surface causes spatial repulsion, preventing Cl− corrosion in seawater electrolysis. The seawater AEM electrolyzer using NiCoPv@NF couple achieves excellent performance of high activity (2.43 V at 500 mA cm−2) and long‐term durability (500 mA cm−2 over 110 h). The working efficiency of AEM in 1.0 M KOH is as high as 77.0% at 100 mA cm−2 with the price of per GGE H2 as low as $ 0.87.

Comparison of the Mechanisms of Hydrolysis of Organophosphates with Good and Poor Leaving Group by Phosphotriesterase from Pseudomonas diminuta

Abstract Combined quantum mechanics/molecular mechanics approaches are used to determine the mechanisms of organophosphate hydrolysis in an active site of Pseudomonas diminuta phosphotriesterase. For a substrate with a good leaving group, the reaction proceeds through two elementary stages with low energy barriers, and a gain in energy is observed. With a poor leaving group, only the formation of an unstable reaction intermediate is possible, and hydrolysis is incomplete. A comparison of the resulting reaction mechanisms explains the experimental kinetic data, according to which the enzyme hydrolyzes only substrates with good leaving groups.

Advanced Structural Engineering Design for Tailored Microporous Structure via Adjustable Graphite Sheet Angle to Enhance Sodium‐Ion Storage in Anthracite‐Based Carbon Anode

AbstractCarbon material has emerged as a highly promising anode for sodium‐ion batteries (SIBs) due to its abundance of resources, cost‐effectiveness, and high carbon yield. This work elaborately designs the precursor structure for the self‐assembly of melamine‐cyanuric acid on the anthracite surface through hydrogen bonding, and successfully constructs N‐doped carbon with tailored microstructure and expanded interlayer spacing. Serving as anode for SIBs, the optimized sample delivers high specific capacity (371.3 mAh g−1 at 0.05 A g−1), superior rate capability (295.8 mAh g−1 at 10.0 A g−1), and excellent ultra‐long cycling performance (the retention of 91.5% after 3000 cycles at 0.5 A g−1). The systematic investigations reveal the enhancement of sodium‐ion storage in the low‐voltage plateau region involving the interlayer intercalation coupled with nanopores filling. It is discovered that the microporous structure formed by the appropriate graphite sheet angle influences the migration and storage of sodium ions. Density functional theory calculations indicate that the adsorption capacity for sodium ion is enhanced and the migration energy barrier perpendicular to the graphite layer is reduced at the appropriate angle of 8°. This study provides novel insights into the sodium‐ion storage mechanism, offering guidance for the better design of anthracite‐based carbon anode with superior performance.

Enhancing the Efficiency of Non Toxic Perovskite Solar Cell through Cs4CuSb2Cl12 as Interface Layer Using SCAPS-1D

Abstract In recent years, Perovskite solar cells (PSC) have showed promising results to substitute traditional PV technologies due to impressive power conversion efficiency (PCE) and cost-effective production. This study investigates the impact of introducing a Cs4CuSb2Cl12 (CCSC) perovskite quantum dot (PQD) interface layer among active layer and hole transport layer (HTL) in CsGeI3 as well as MAGeI3-based PSCs. It aims in enhancing the function of interface layer (IL) by improving PCE while reducing interface losses. TiO2 and Spiro-OMeTAD were employed as the electron transport layer (ETL) and HTL, respectively. SCAPS-1D software was utilized for simulating JSC, VOC, FF, and PCE of various configurations, including passivated and non-passivated structures. The results revealed a substantial increase in JSC from 13.22 mA/cm2 to 15.5 mA/cm2 and PCE from 11.67% to 14.81% for MAGeI3-based PSCs with incorporated PQD layer. Additionally, the fill factor (FF) improved from 50.55% to 76.90%. However, a decrease in VOC from 1.7 V towards 1.24 V was noticed, this was associated with the formation of an energy barrier at HTL/ absorber. For CsGeI3-based devices, a slight improvement in JSC was observed from 21.0 mA/cm2 to 21.8 mA/cm2, whereas VOC remained constant at 1.24 V. The PCE increased from 22.50% to 23.09%, but the FF decreased from 86.83% to 85.48%. However the decrease in the fill factor (FF) may be attributable to a rise in the cell series resistance due to the additional interface, which could impede charge transport and extraction. This simulation study demonstrates that the incorporation of a CCSC PQD IL among active layer / HTL can enhance the PCE and short circuit current of CsGeI3 and MAGeI3-based PSCs, providing a promising avenue for future optimizations and advancements in PSC technologies.

In Operando X-ray Spectroscopic and DFT Studies Revealing Improved H2 Evolution by the Synergistic Ni-Co Electron Effect in the Alkaline Condition.

The different electrolyte conditions, e.g., pH value, for driving efficient HER and OER are one of the major issues hindering the aim for electrocatalytic water splitting in a high efficiency. In this regard, seeking durable and active HER electrocatalysts to align the alkaline conditions of the OER is a promising solution. However, the success in this strategy will depend on a fundamental understanding about the HER mechanism at the atomic scale. In this work, we have provided thorough understanding for the electrochemical HER mechanisms in KOH over Ni- and Co-based hollow pyrite microspheres by in operando X-ray spectroscopies and DFT calculations, including NiS2, CoS2, and Ni0.5Co0.5S2. We discovered that the Ni sites in hollow NiS2 microspheres were very stable and inert, while the Co sites in hollow CoS2 microspheres underwent reduction and generated Co metallic crystal domains under HER. The generation of Co metallic sites would further deactivate H2 evolution due to the large hydrogen desorption free energy (-1.73 eV). In contrast, the neighboring Ni and Co sites in hollow Ni0.5Co0.5S2 microspheres exhibited the electronic interaction to elevate the reactivity of Ni and facilitate the stability of Co without structure or surface degradation. The energy barrier in H2O adsorption/dissociation was only 0.73 eV, followed by 0.06 eV for hydrogen desorption over the Ni0.5Co0.5S2 surface, revealing Ni0.5Co0.5S2 as a HER electrocatalyst with higher durability and activity than NiS2 and CoS2 in the alkaline medium due to the synergy of neighboring Ni and Co sites. We believe that the findings in our work offer a guidance toward future catalyst design.

General Synthesis of Metal Indium Sulfide Atomic Layers for Photocatalysis.

The metal indium sulfides have attracted extensive research interest in photocatalysis due to regulable atomic configuration and excellent optoelectronic properties. However, the synthesis of metal indium sulfide atomic layers is still challenging since intrinsic non-van-der-Waals layered structures of some components. Here, a surfactant self-assembly growth mechanism is proposed to controllably synthesize metal indium sulfide atomic layers. Eleven types of atomic layers with tunable compositions, thickness, and defect concentrations are successfully achieved namely In2S3, MgIn2S4, CaIn2S4, MnIn2S4, FeIn2S4, ZnIn2S4, Zn2In2S5, Zn4In16S33, CuInS2, CuIn5S8, and CdIn2S4. The typical CaIn2S4 shows a defect-dependence activity for CO2 photoreduction. The designed S vacancies in CaIn2S4 can serve as catalytic centers to activate CO2 molecules via localized electrons for π-back-donation. The engineered S vacancies tune the non-covalent interaction with CO2 and intermediates, manages to tune the free energy, and lower the reaction energy barrier. As a result, the defect-rich CaIn2S4 displays 2.82× improved reduction rate than defect-poor CaIn2S4. Meantime, other components also display promising photocatalytic performance, such as Zn2In2S5 with a H2O2 photosynthesis rate of 292µmolg-1h-1 and CuInS2 with N2-NH4 + conversion rate of 54µmolg-1h-1. This work paves the way for the multidisciplinary exploration of metal indium sulfide atomic layers with unique photocatalysis properties.

Mechanistic understanding of the acceptorless dehydrogenation reaction catalyzed by low valent Co(I) complex

Coordination complexes based on the first-row transition metal play pivotal role in homogenous catalysis. However, the variable oxidation states and complicated electronic configurations of first-row transition metal centers result in the ambiguous mechanism. Herein, focusing on a typical Co(Ⅰ)-PNP pincer catalyst developed by Madsen et al. (Chemcatchem, 11 (2019) 2707–2712.), the diversity of mechanistic scenarios caused by low valent cobalt complex is displayed and the competition of each plausible reaction pathways were investigated based on density functional theory (DFT) calculation. The calculated results suggest that the MLC mechanism mediated by Co(I) center prevails in different stage among all possible reaction pathways. Further analysis using the activation strain model elucidates the dual active sites in MLC mechanism leads to a higher interaction energy compared with the Co(I/III) mechanism, in which the reaction basically occurs on the metal center. However, in the high spin state, the metal and the ligand cooperate to provide more interaction energy in the activation of chemical bonds, thereby reducing the activation energy barrier. These theoretical findings are anticipated to enhance current understanding of homogeneous catalysis based on 3d low valent metal centers.

Dearomative [2 + 1] Spiroannulation of Bromophenols with Electron-Deficient Alkenes.

A base-assisted dearomative [2 + 1] spiroannulation of p/o-bromophenols with activated olefins (methylenemalonates) to construct various cyclopropyl spirocyclohexadienone skeletons is reported. Furthermore, several other halophenols (X = Cl, I) were also tolerated in this process. Control experiments reveal a dearomative Michael addition of phenols at their halogenated positions to methylenemalonates, followed by intramolecular radical-based SRN1 dehalogenative cyclopropanation. However, according to the density functional theory (DFT) calculations, an SN2 dehalogenative cyclopropanation with the same low activation energy barrier should not be excluded. The utility of this method is showcased by gram-scale syntheses and transformations of the dearomatized products.

Finite dimension of the ion pathway networks in conducting glasses

In disordered materials, the ordinary understanding is that charge carriers tend to occupy energetically favorable sites known as ion-conducting channels. Many studies have revealed that the inherent fractal properties of such pathways lead to a sub-diffusive behavior. The linearity or branching of these pathways is crucial for determining how the charge carriers move. It can be thought that as the space dimensionality decreases, the average distance between the highest energy barriers along the conduction paths increases. In this study the finite dimension of those pathways is computed using an extended version of the classical Hausdorff dimension. Also, the Arrhenius behavior of the most mobile lithium ions is proved, confirming that such are responsible for conductivity behavior. The lithium ions mobility behavior in response to temperature changes and the finite dimension allowed to identify the ion diffusion regions fractal features. The reported results demonstrate that as the temperature increases the conducting channels become broadener, facilitating the transfer of electrical charge through the glassy matrix, below the transition temperature. The pathways behavior confirms the increase of the ionic conductivity when the temperature increases as it is experimentally observed.

High‐Density Rare‐Earth Single‐Atom‐Triggered Unconventional Transition of Adsorption Configuration on La1Pd Monatomic Alloy Metallene for Sustainable Electrocatalytic Alkynol Semi‐Hydrogenation

AbstractElectrocatalytic alkynol semi‐hydrogenation for the high‐value chemicals alkenol with mild conditions and carbon‐free emission is a potentially green and sustainable alternative to conventional thermocatalytic routes, which generally involves the design of electrocatalysts with high activity and high selectivity. Here, the rare‐earth single‐atom (Ln = La, Nd, Pr) coordinated Pd metallene (Ln1Pdene) is reported for electrocatalytic 2‐methyl‐3‐butyn‐2‐ol (MBY) semi‐hydrogenation reaction (MBY ESHR) to synthesis of 2‐methyl‐3‐buten‐2‐ol (MBE). Typically, in alkaline medium containing 0.1 m MBY, MBY conversion and MBE selectivity of La1Pdene are as high as ≈97% and ≈95%, respectively, with excellent electrocatalytic stability. Meanwhile, in situ infrared spectra reveal the conversion of MBY to MBE during the dynamic electrocatalytic process. Theoretical calculations reveal that the interaction between La single‐atom and Pd host triggers an unconventional transformation of the intermediate MBE* adsorption configuration during electrocatalytic hydrogenation, achieving the optimal desorption energy between La1Pd and target product and optimizing the reaction energy barriers to inhibit the over‐hydrogenation of MBE. Moreover, La single‐atom as the adsorption active site of the hydrogen supplier H2O effectively reduces the competition adsorption between the reactants MBY and H2O, rendering La single‐atom and Pd host as the synergistic co‐catalytic active sites to promote the electrocatalytic MBY semi‐hydrogenation reaction.

Understanding the depolarization phenomena in (1−x) Na0.5Bi0.5TiO3. (x) Ba0.85Ca0.15Ti0.90Zr0.10O3 solid solutions using in-situ temperature dependent Raman spectroscopy

A decrease in depolarization temperature (T d) from 456 K to 352 K was observed with an increase in BCZT substitution in the NBT for the (1−x) Na0.5Bi0.5TiO3. (x) Ba0.85Ca0.15Ti0.90Zr0.10O3 solid solutions. A transition towards a higher ergodic state was elucidated with an increase in BCZT content that helped to reduce the free energy barrier, hence lesser thermal energy was required to depolarize the modified systems. Furthermore, a decrease in remnant polarization and coercive field, coupled with an increase in energy storage (W stored) and efficiency (η%) with higher BCZT content. In-situ temperature-dependent Raman spectra provide additional insights, highlighting the faster changes in phonon shifts and lifetimes corresponding to the A–O, B–O, and BO6 vibrations around the depolarization temperature (T d). The observed phase transformation to a P4bm phase at temperatures significantly higher than T d is substantiated by Raman shift and phonon lifetime variations in the modes associated with the A–O and B–O vibrations. The transitions can be understood as: at T ∼ T d the polar nano regions (PNRs) start to appear due to weakening of bonds, T > T d all the long-range ferroelectric domains transform to PNRs converting the material to a fully ergodic state, and at much higher temperatures (T ≫ T d) the R3c PNRs vanish and P4bm PNRs appear.