The work couples bismuth ferrite with Ta₂O₅ and follows Fe and Ta under operating conditions. Diffraction, spectroscopy, and microscopy confirm direct contact between the two oxide phases, while impedance resolves Maxwell-Wagner interfacial polarization.
After all seventeen operando Fe K-edge spectra are placed on a common normalization, no change in the bulk-averaged Fe oxidation state is resolved. The reversible component is bounded at less than 1.4% of the charge stored in one cycle across the illuminated volume.
This does not exclude Fe redox confined to the particle surface. XPS resolves mixed Fe²⁺/Fe³⁺ character, so near-surface Fe redox remains consistent with the evidence, but operando XAS does not demonstrate it directly.
At the Ta L₃-edge, Ta remains at the Ta⁵⁺ end of the reference interval and its first Ta-O shell is unchanged. No Ta-centred redox transformation is therefore assigned; Ta₂O₅ is instead treated as an interfacial and polarization component.
The mechanism is bounded by measurement, not asserted from performance.
The composite delivers 156 F g⁻¹ at 1 mV s⁻¹. A symmetric device reaches 34 Wh kg⁻¹ at 558 W kg⁻¹ and retains 82% of its capacitance after 10,000 cycles.
The interpretation remains deliberately limited: dielectric response and electrochemical kinetics are measured over different length scales, and bulk-averaged XAS cannot isolate a surface-confined reaction. Within those bounds, the work supports a practical principle—pair a redox-active perovskite with a high-permittivity insulator, then verify their division of labour spectroscopically rather than inferring it from performance.
Selvaraj Y., Nangan S., Gopalakrishnan M., Venkattappan A., Eswaramoorthy N., Kao-ian W., Limphirat W., Yu S.-H., Kheawhom S. Coupled dielectric polarization and Fe redox charge storage in Ta₂O₅/bismuth ferrite heterostructures for aqueous supercapacitors. Journal of Alloys and Compounds (2026) 190516. DOI 10.1016/j.jallcom.2026.190516
]]>He spent far more time asking how they could become better.
Not only better scholars.
Better human beings.
Reading his teachings, I sometimes wonder what he might say to a professor.
Perhaps he would not ask about publications.
Or citations.
Or awards.
Perhaps he would ask a quieter question.
Who will grow because you were here?
It is a different way of measuring an academic life.
Universities celebrate many achievements.
Papers published.
Grants awarded.
Students graduated.
Rankings improved.
These accomplishments matter.
They advance knowledge and strengthen institutions.
But they are only part of a professor’s contribution.
Every lecture shapes the way someone thinks.
Every conversation encourages—or discourages—a young researcher.
Every piece of thoughtful feedback helps someone take the next step.
Many of these moments will never appear on a curriculum vitae.
Yet they may become our most enduring work.
Knowledge is not diminished by being shared.
It grows.
Perhaps this is why teaching has always been more than the transfer of information.
It is the cultivation of judgment.
Curiosity.
Integrity.
The confidence to ask difficult questions.
And the humility to change one’s mind when the evidence demands it.
A professor’s influence is rarely measured at the moment it is given.
Sometimes its true value becomes visible years later.
In a former student who mentors others with the same generosity.
In a young researcher who learns to value truth over recognition.
In a future discovery made possible because someone once took the time to teach patiently.
Confucius understood that education is never only about knowledge.
It is about character.
The facts we teach today may eventually be revised.
The habits of mind we help cultivate may last a lifetime.
Perhaps this is the quiet privilege of being a professor.
We contribute not only to the literature.
We contribute to the people who will write the next chapters of that literature.
Every morning, a professor should ask one simple question:
Who will become a better scholar—and a better person—because of something I do today?
Perhaps the most lasting measure of an academic career is not the papers we leave behind.
Perhaps it is the people who continue to learn, teach, and inspire long after we are gone.
]]>It is that we waste much of it.
Nearly two thousand years later, his words still feel uncomfortably familiar.
Especially in academia.
Researchers rarely complain about a lack of intelligence.
Or curiosity.
Or ideas.
We complain about a lack of time.
There is always another email.
Another committee meeting.
Another proposal.
Another manuscript to review.
Another administrative task that seems impossible to postpone.
Days become weeks.
Weeks become years.
And one day we realize that we have spent much of our career responding to urgency rather than pursuing importance.
Seneca would probably ask a simple question.
What are you spending your life on?
Not your calendar.
Your life.
The two are not always the same.
Busyness can easily become a substitute for progress.
A full schedule can create the comforting illusion that meaningful work is being done.
Yet activity and contribution are not synonymous.
The most important ideas rarely emerge between meetings.
They require uninterrupted time.
Quiet reflection.
Careful reading.
Patient thinking.
The kind of work that often leaves nothing visible on today’s to-do list.
Science has always demanded more than productivity.
It demands attention.
Attention to unexpected observations.
Attention to inconvenient results.
Attention to questions that refuse simple answers.
Perhaps the greatest resource in research is not funding.
Nor equipment.
Nor even talent.
It is sustained attention directed toward a worthwhile question.
Seneca reminds us that time is more than a resource to be managed.
It is the substance from which a life is made.
Every hour we spend is an hour we can never recover.
That realization is not meant to create anxiety.
It is meant to sharpen intention.
To ask not whether we are busy.
But whether we are becoming the kind of researcher we hoped to become.
Every morning, a researcher should ask one simple question:
If today were one page in the story of my scientific life, would it be worth keeping?
Perhaps the measure of a scientific career is not how full our days have been.
Perhaps it is whether we gave our best time to the questions that mattered most.
]]>A lithium ion carries a charge of +1. A sodium ion does too. Magnesium and zinc both carry +2. It is tempting to think that ionic charge and size should tell us how these ions behave in an electrolyte.
They do not.
Consider Mg²⁺ and Zn²⁺. Both are divalent, and their ionic sizes are comparable. Yet their electrochemical behavior can be remarkably different. Mg²⁺ strongly binds its surrounding ligands and often pays a substantial energetic and kinetic penalty when its coordination shell must reorganize near an electrode. Zn²⁺, in contrast, can access a wider range of coordination environments, with water, anions, and additives competing to define the species that actually reaches the interface.
The difference is not simply charge. It is coordination chemistry.
When we write an electrochemical reaction as
the notation hides much of the chemistry.
In an electrolyte, the reacting species is rarely a bare Mz+. It exists within a local coordination environment containing solvent molecules, anions, and sometimes specifically designed ligands or additives.
A more realistic starting point is therefore something like
and x and y are not merely structural details. They influence how the ion moves, how easily its coordination shell can reorganize, what reaches the electrode surface, and what ultimately reacts there.
Across common battery charge carriers, coordination behavior changes substantially.
Li⁺ is small and forms a compact solvation environment, commonly dominated by oxygen donors. Na⁺ is larger and generally supports a more flexible coordination shell with higher coordination numbers.
Moving to divalent ions changes the problem. Mg²⁺ combines small size with +2 charge, producing strong interactions with surrounding ligands and a relatively persistent first coordination shell. This can make coordination-shell reorganization and desolvation major kinetic barriers.
Zn²⁺ provides an instructive counterexample. It has the same formal charge as Mg²⁺, but its coordination landscape is considerably more diverse. Coordination numbers and geometries can change with solvent, anion, concentration, and additives. For Zn electrochemistry, controlling which species exists can therefore be as important as controlling how fast that species moves.
Al³⁺ takes the trend further. Its high charge density strongly polarizes coordinated molecules. In water, coordination is no longer merely a question of solvation: it can drive hydrolysis and change the chemical identity of the species itself.
These comparisons suggest that ionic charge and radius are useful starting descriptors, but not sufficient ones.
Even coordination number does not tell the complete story.
Two ions may both have six coordinating oxygen atoms and still behave very differently. We also need to ask:
This distinction is important because
The relevant quantity is therefore not a single coordination structure, but a coordination landscape: the accessible structures, their relative free energies, and the pathways connecting them.
This leads to a causal sequence:
The first coordination shell determines what the ion carries with it through the electrolyte. Transport determines how that coordinated species reaches the interface. Near the electrode, the coordination environment must reorganize again before electron transfer, insertion, or metal deposition can occur.
The species observed in the bulk electrolyte is therefore not necessarily the species that reacts at the electrode.
That distinction matters.
An electrolyte can have high ionic conductivity while presenting an unfavorable coordination environment for interfacial charge transfer. Conversely, modifying an anion or adding a ligand may improve electrochemical reversibility even when bulk conductivity decreases.
The fastest electrolyte is not necessarily the best electrolyte.
This is why we place Coordination at the beginning of our Coordination–Transport–Interface (CTI) framework.
Coordination asks what chemical state the charge carrier actually occupies.
Transport asks how that state moves and evolves through the electrolyte.
Interface asks what remains of that coordination environment when the ion encounters an electrode and undergoes electrochemical transformation.
Li⁺, Na⁺, Mg²⁺, Zn²⁺, and Al³⁺ provide different answers to these questions. Comparing them may reveal something more general than the behavior of any individual battery chemistry.
It may reveal why an ion’s electrochemical identity is determined not only by what it is, but also by what it is coordinated to.
]]>Not comfort.
Not success.
Meaning.
Reading his work, I sometimes wonder what he might ask a researcher.
Perhaps it would not be about publications.
Or citations.
Or the H-index.
Perhaps he would simply ask:
Why are you doing this?
At the beginning of an academic career, the answer often seems obvious.
To complete a degree.
To publish the first paper.
To secure a position.
To build a laboratory.
To earn recognition from the scientific community.
These are worthwhile goals.
They give direction to our early years.
But as the years pass, another question quietly emerges.
When the next paper is published…
What comes next?
When the next grant is awarded…
What comes next?
When the next promotion arrives…
What comes next?
A career built only on milestones can become an endless pursuit of the next milestone.
Frankl might remind us that achievement and meaning are not the same.
Achievement answers the question,
“What have I accomplished?”
Meaning asks,
“Why does this matter?”
Research becomes more sustainable when it is connected to something larger than ourselves.
Perhaps it is the desire to understand nature more deeply.
Perhaps it is the hope that our work will improve people’s lives.
Perhaps it is the privilege of mentoring young scientists who will one day go further than we can.
Whatever the answer, meaning gives purpose to the long days that no one sees.
The failed experiments.
The rejected manuscripts.
The unsuccessful grant proposals.
The months when progress seems invisible.
Without meaning, these moments feel like obstacles.
With meaning, they become part of the journey.
Frankl never suggested that life would be free of difficulty.
He suggested that difficulty becomes bearable when we understand why we choose to endure it.
Perhaps research is no different.
Every worthwhile scientific question demands patience.
Every meaningful contribution requires persistence.
Not because success is guaranteed.
But because some questions are worth pursuing regardless of how long the answer takes.
Every morning, a researcher should ask one simple question:
If recognition were guaranteed to disappear tomorrow, would this work still be worth doing?
The answer may reveal not only the purpose of today’s research.
It may reveal the purpose of the researcher.
]]>No laboratory.
No equations.
Yet he may have given us one of the most enduring lessons for scientific life.
The more we learn, the more clearly we see how much remains unknown.
This is often mistaken for modesty.
It is something deeper.
It is intellectual honesty.
As researchers, we spend our lives acquiring knowledge.
We publish papers.
We develop expertise.
We become recognized in increasingly specialized fields.
With time, others begin calling us experts.
There is nothing wrong with expertise.
Science depends on it.
But expertise creates an illusion.
It makes the boundary between the known and the unknown appear smaller than it really is.
Socrates would gently remind us that the opposite is often true.
Every genuine discovery expands the horizon of what we do not yet understand.
The deeper we explore, the farther that horizon moves away.
Knowledge grows.
So does the unknown.
Not because the world has become more mysterious.
But because we have finally learned enough to recognize mysteries we could not even see before.
Perhaps this is why the greatest scientists often speak with remarkable humility.
Not because they know less.
But because they have seen how vast the unknown truly is.
In science, confidence is earned.
Certainty is dangerous.
Curiosity, however, never becomes obsolete.
A researcher who believes there is nothing left to learn has quietly stopped being a researcher.
The willingness to say, “I don’t know,” is not a sign of weakness.
It is the beginning of discovery.
Every morning, a researcher should ask one simple question:
What part of today’s certainty might become tomorrow’s ignorance?
Perhaps wisdom is not measured by how much we know.
Perhaps it is measured by how much of the unknown we are still willing to explore.
]]>He suggested that science does not always advance by adding new knowledge to old knowledge.
Sometimes, it advances by changing the way we see the problem itself.
At first, this seems difficult to imagine.
Most researchers are trained to solve problems.
We refine methods.
We improve accuracy.
We collect better data.
We explain phenomena more precisely.
Progress often feels like moving one careful step at a time.
But Kuhn would probably ask a different question.
What assumptions are you taking for granted?
That question is unsettling.
Because assumptions are often invisible.
We rarely question the ideas that everyone around us accepts.
We inherit definitions.
We inherit models.
We inherit ways of interpreting data.
Eventually, they become so familiar that they no longer feel like assumptions at all.
They simply become “the way science works.”
Most of the time, that is exactly how science should progress.
Normal science depends on shared frameworks.
Without them, researchers could not build on one another’s work.
But every framework has limits.
Sooner or later, observations begin to appear that do not fit comfortably within the existing picture.
At first, they seem like exceptions.
Then they become recurring anomalies.
Eventually, they force a more difficult question.
Perhaps the problem is not the data.
Perhaps the problem is the framework we are using to understand the data.
History reminds us that this has happened many times.
The Earth did not change when astronomy changed.
Atoms did not change when quantum mechanics emerged.
Nature remained the same.
Only our understanding became deeper.
Perhaps this is one of the quiet lessons of scientific life.
Sometimes the greatest obstacle to discovery is not the absence of evidence.
It is the presence of assumptions that no one thinks to question.
This does not mean rejecting established knowledge.
Scientific progress depends on the careful work of normal science.
Most discoveries are made by improving what already exists.
Yet every generation of researchers should occasionally ask whether the questions themselves deserve re-examination.
The future rarely belongs only to those who produce more data.
It also belongs to those who learn to see familiar data in unfamiliar ways.
Every morning, a researcher should ask one simple question:
What assumption am I making that I have never stopped to examine?
The answer may not change today’s experiment.
But it may change the question that defines tomorrow’s science.
]]>The first principle is that you must not fool yourself—and you are the easiest person to fool.
At first glance, this sounds obvious.
Surely scientists are trained to be objective.
Surely years of education teach us how to separate evidence from belief.
Yet experience suggests otherwise.
The greatest challenge in research is often not convincing others.
It is recognizing the subtle ways we convince ourselves.
We all begin with expectations.
We hope an experiment will work.
We believe our hypothesis makes sense.
We want months—or years—of effort to lead somewhere meaningful.
There is nothing wrong with hope.
The danger begins when hope quietly becomes interpretation.
When we notice only the data that support our idea.
When we explain away the results that do not.
When we repeat an experiment, not because we seek the truth, but because we hope for a different answer.
Self-deception rarely arrives as dishonesty.
More often, it appears as optimism.
As confidence.
As the quiet belief that our explanation must be correct because we have invested so much in it.
This is precisely why Feynman’s warning remains timeless.
The easiest person to deceive is not our reviewer.
Not our colleague.
Not our competitor.
It is ourselves.
Science protects us from that temptation through discipline.
Careful experimental design.
Appropriate controls.
Independent replication.
Critical discussions with colleagues.
Peer review.
These are not obstacles placed in the way of discovery.
They are safeguards against our own certainty.
Perhaps this is why the best researchers are often the first to question their own conclusions.
Not because they lack confidence.
But because they understand how easily confidence can become bias.
Confidence builds ideas.
Humility tests them.
Both are necessary.
Without confidence, we would never attempt difficult questions.
Without humility, we might never recognize when the answers are trying to correct us.
Every morning, a researcher should ask one simple question:
Am I following the evidence—or am I following my expectations?
The answer may determine not only the quality of today’s experiment.
It may determine whether we discover the truth—or merely confirm what we already wanted to believe.
]]>Science advances not by proving ideas right, but by discovering where they fail.
At first, this sounds counterintuitive.
Researchers spend years developing hypotheses, designing experiments, collecting data, and writing papers. Naturally, we hope our ideas will be supported.
Yet Popper would probably ask a different question.
How could you find out that your hypothesis is wrong?
That question changes everything.
Many of us begin a project hoping to confirm what we already believe.
We search for evidence that supports our hypothesis.
We feel encouraged when the data align with our expectations.
We feel disappointed when they do not.
But science asks something more demanding.
It asks us to challenge our own ideas with the same honesty that we would challenge someone else’s.
A hypothesis is valuable not because it explains existing observations.
A hypothesis becomes scientific because it can be tested—and because it can, in principle, be shown to be wrong.
This is what makes research different from advocacy.
Our responsibility is not to defend an idea.
Our responsibility is to discover whether the idea survives careful examination.
That is not always easy.
When experiments fail, we often feel that we have failed.
When reviewers criticize our interpretation, we instinctively prepare a defense.
When results contradict years of work, the temptation is to search for reasons why the data must be mistaken.
But perhaps these moments deserve a different interpretation.
A failed experiment is not always a failed study.
A critical reviewer is not always an obstacle.
Unexpected data are not always bad news.
Sometimes they are the first signs that reality is teaching us something our hypothesis could not.
The history of science is filled with ideas that endured for years before better evidence replaced them.
Progress did not occur because scientists protected those ideas.
Progress occurred because someone was willing to ask a difficult question, perform a decisive experiment, and accept the answer.
Perhaps this is the quiet courage that Popper asks of every researcher.
Not the courage to defend our theories.
But the courage to test them where they are most likely to fail.
This does not diminish the importance of creativity.
Every important discovery begins with imagination.
But imagination alone is not enough.
Our best ideas earn their place only after they have survived our most rigorous attempts to disprove them.
Perhaps the greatest mistake in research is not being wrong.
It is holding an idea in a way that no evidence could ever challenge.
Every morning, a researcher should ask one simple question:
What evidence would convince me that I am wrong?
Science moves forward not because we avoid being wrong.
It moves forward because we are willing to discover when we are.
]]>He taught them how to understand suffering.
At first, this may seem far removed from scientific research.
But I sometimes wonder whether researchers experience a unique form of suffering that is rarely discussed.
We become attached.
Not only to publications.
Not only to citations.
Not only to grants or recognition.
We become attached to our own ideas.
To our hypotheses.
To the experiments we hope will work.
To the theories we have spent years developing.
To the belief that we are right.
There is nothing wrong with commitment.
Science requires commitment.
What it does not require is attachment.
A researcher begins with a hypothesis.
But a scientist must also be willing to let it go.
The purpose of research is not to prove ourselves correct.
It is to discover what is true.
Sometimes those two paths lead in the same direction.
Sometimes they do not.
The most difficult moments in science are often not technical.
They are psychological.
When the data refuse to support our favorite idea.
When another group publishes first.
When a reviewer points out a flaw we failed to see.
When years of work lead to a conclusion different from the one we hoped for.
In those moments, suffering rarely comes from the data themselves.
It comes from our attachment to the outcome we wanted.
The Buddha repeatedly reminded his followers that attachment is often the beginning of suffering.
Perhaps researchers need the same reminder.
This does not mean becoming indifferent.
It does not mean losing ambition.
It does not mean caring less about excellent science.
Quite the opposite.
It means caring more about the truth than about being right.
It means welcoming evidence, even when it asks us to change our minds.
It means having the humility to revise our conclusions when better data emerge.
In that sense, good science is an exercise in letting go.
Not of curiosity.
Not of rigor.
Not of excellence.
But of certainty.
Every experiment is, in its own way, a lesson in impermanence.
Every hypothesis is provisional.
Every conclusion remains open to better evidence.
Perhaps this is why science continues to advance.
Not because scientists never make mistakes.
But because the best scientists are willing to release yesterday’s certainty in order to understand today’s reality.
Every morning, a researcher has only one responsibility.
]]>Observe carefully.
Think honestly.
Follow the evidence.
Let go of what the evidence cannot support.
Then begin again.